Commit Graph

51781 Commits

Author SHA1 Message Date
Tejun Heo
207d76a372 sched_ext: Pass held rq to SCX_CALL_OP() for dump_cpu/dump_task
scx_dump_state() walks CPUs with rq_lock_irqsave() held and invokes
ops.dump_cpu / ops.dump_task with NULL locked_rq, leaving
scx_locked_rq_state NULL. If the BPF callback calls a kfunc that
re-acquires rq based on scx_locked_rq() - e.g. scx_bpf_cpuperf_set(cpu)
- it re-acquires the already-held rq.

Pass the held rq to SCX_CALL_OP(). Thread it into scx_dump_task() too.
The pre-loop ops.dump call runs before rq_lock_irqsave() so keeps
rq=NULL.

Fixes: 07814a9439 ("sched_ext: Print debug dump after an error exit")
Cc: stable@vger.kernel.org # v6.12+
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-24 14:31:36 -10:00
Tejun Heo
7fb39e4eb4 sched_ext: Save and restore scx_locked_rq across SCX_CALL_OP
SCX_CALL_OP{,_RET}() unconditionally clears scx_locked_rq_state to NULL on
exit. Correct at the top level, but ops can recurse via
scx_bpf_sub_dispatch(): a parent's ops.dispatch calls the helper, which
invokes the child's ops.dispatch under another SCX_CALL_OP. When the inner
call returns, the NULL clobbers the outer's state. The parent's BPF then
calls kfuncs like scx_bpf_cpuperf_set() which read scx_locked_rq()==NULL and
re-acquire the already-held rq.

Snapshot scx_locked_rq_state on entry and restore on exit. Rename the rq
parameter to locked_rq across all SCX_CALL_OP* macros so the snapshot local
can be typed as 'struct rq *' without colliding with the parameter token in
the expansion. SCX_CALL_OP_TASK{,_RET}() and SCX_CALL_OP_2TASKS_RET() funnel
through the two base macros and inherit the fix.

Fixes: 4f8b122848 ("sched_ext: Add basic building blocks for nested sub-scheduler dispatching")
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-24 14:31:36 -10:00
Tejun Heo
2f2ea77092 sched_ext: Use dsq->first_task instead of list_empty() in dispatch_enqueue() FIFO-tail
dispatch_enqueue()'s FIFO-tail path used list_empty(&dsq->list) to decide
whether to set dsq->first_task on enqueue. dsq->list can contain parked BPF
iterator cursors (SCX_DSQ_LNODE_ITER_CURSOR), so list_empty() is not a
reliable "no real task" check. If the last real task is unlinked while a
cursor is parked, first_task becomes NULL; the next FIFO-tail enqueue then
sees list_empty() == false and skips the first_task update, leaving
scx_bpf_dsq_peek() returning NULL for a non-empty DSQ.

Test dsq->first_task directly, which already tracks only real tasks and is
maintained under dsq->lock.

Fixes: 44f5c8ec5b ("sched_ext: Add lockless peek operation for DSQs")
Cc: stable@vger.kernel.org # v6.19+
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
Cc: Ryan Newton <newton@meta.com>
2026-04-24 14:31:35 -10:00
Tejun Heo
cc2a387d33 sched_ext: Resolve caller's scheduler in scx_bpf_destroy_dsq() / scx_bpf_dsq_nr_queued()
scx_bpf_create_dsq() resolves the calling scheduler via scx_prog_sched(aux)
and inserts the new DSQ into that scheduler's dsq_hash. Its inverse
scx_bpf_destroy_dsq() and the query helper scx_bpf_dsq_nr_queued() were
hard-coded to rcu_dereference(scx_root), so a sub-scheduler could only
destroy or query DSQs in the root scheduler's hash - never its own. If the
root had a DSQ with the same id, the sub-sched silently destroyed it and the
root aborted on the next dispatch ("invalid DSQ ID 0x0..").

Take a const struct bpf_prog_aux *aux via KF_IMPLICIT_ARGS and resolve the
scheduler with scx_prog_sched(aux), matching scx_bpf_create_dsq().

Fixes: ebeca1f930 ("sched_ext: Introduce cgroup sub-sched support")
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-24 14:31:35 -10:00
Tejun Heo
80afd4c84b sched_ext: Read scx_root under scx_cgroup_ops_rwsem in cgroup setters
scx_group_set_{weight,idle,bandwidth}() cache scx_root before acquiring
scx_cgroup_ops_rwsem, so the pointer can be stale by the time the op runs.
If the loaded scheduler is disabled and freed (via RCU work) and another is
enabled between the naked load and the rwsem acquire, the reader sees
scx_cgroup_enabled=true (the new scheduler's) but dereferences the freed one
- UAF on SCX_HAS_OP(sch, ...) / SCX_CALL_OP(sch, ...).

scx_cgroup_enabled is toggled only under scx_cgroup_ops_rwsem write
(scx_cgroup_{init,exit}), so reading scx_root inside the rwsem read section
correlates @sch with the enabled snapshot.

Fixes: a5bd6ba30b ("sched_ext: Use cgroup_lock/unlock() to synchronize against cgroup operations")
Cc: stable@vger.kernel.org # v6.18+
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-24 14:31:35 -10:00
Tejun Heo
21a5a97ba4 sched_ext: Don't disable tasks in scx_sub_enable_workfn() abort path
scx_sub_enable_workfn()'s prep loop calls __scx_init_task(sch, p, false)
without transitioning task state, then sets SCX_TASK_SUB_INIT. If prep fails
partway, the abort path runs __scx_disable_and_exit_task(sch, p) on the
marked tasks. Task state is still the parent's ENABLED, so that dispatches
to the SCX_TASK_ENABLED arm and calls scx_disable_task(sch, p) - i.e.
child->ops.disable() - for tasks on which child->ops.enable() never ran. A
BPF sub-scheduler allocating per-task state in enable/freeing in disable
would operate on uninitialized state.

The dying-task branch in scx_disable_and_exit_task() has the same problem,
and scx_enabling_sub_sched was cleared before the abort cleanup loop - a
task exiting during cleanup tripped the WARN and skipped both ops.exit_task
and the SCX_TASK_SUB_INIT clear, leaking per-task resources and leaving the
task stuck.

Introduce scx_sub_init_cancel_task() that calls ops.exit_task with
cancelled=true - matching what the top-level init path does when init_task
itself returns -errno. Use it in the abort loop and in the dying-task
branch. scx_enabling_sub_sched now stays set until the abort loop finishes
clearing SUB_INIT, so concurrent exits hitting the dying-task branch can
still find @sch. That branch also clears SCX_TASK_SUB_INIT unconditionally
when seen, leaving the task unmarked even if the WARN fires.

Fixes: 337ec00b1d ("sched_ext: Implement cgroup sub-sched enabling and disabling")
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-24 14:31:35 -10:00
Tejun Heo
da2d81b411 sched_ext: Skip tasks with stale task_rq in bypass_lb_cpu()
bypass_lb_cpu() transfers tasks between per-CPU bypass DSQs without
migrating them - task_cpu() only updates when the donee later consumes the
task via move_remote_task_to_local_dsq(). If the LB timer fires again before
consumption and the new DSQ becomes a donor, @p is still on the previous CPU
and task_rq(@p) != donor_rq. @p can't be moved without its own rq locked.

Skip such tasks.

Fixes: 95d1df610c ("sched_ext: Implement load balancer for bypass mode")
Cc: stable@vger.kernel.org # v6.19+
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-24 14:31:35 -10:00
Tejun Heo
4fda9f0e7c sched_ext: Guard scx_dsq_move() against NULL kit->dsq after failed iter_new
bpf_iter_scx_dsq_new() clears kit->dsq on failure and
bpf_iter_scx_dsq_{next,destroy}() guard against that. scx_dsq_move() doesn't -
it dereferences kit->dsq immediately, so a BPF program that calls
scx_bpf_dsq_move[_vtime]() after a failed iter_new oopses the kernel.

Return false if kit->dsq is NULL.

Fixes: 4c30f5ce4f ("sched_ext: Implement scx_bpf_dispatch[_vtime]_from_dsq()")
Cc: stable@vger.kernel.org # v6.12+
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-24 14:31:35 -10:00
Tejun Heo
411d3ef1a7 sched_ext: Unregister sub_kset on scheduler disable
When ops.sub_attach is set, scx_alloc_and_add_sched() creates sub_kset as a
child of &sch->kobj, which pins the parent with its own reference. The
disable paths never call kset_unregister(), so the final kobject_put() in
bpf_scx_unreg() leaves a stale reference and scx_kobj_release() never runs,
leaking the whole struct scx_sched on every load/unload cycle.

Unregister sub_kset in scx_root_disable() and scx_sub_disable() before
kobject_del(&sch->kobj).

Fixes: ebeca1f930 ("sched_ext: Introduce cgroup sub-sched support")
Reported-by: Chris Mason <clm@meta.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-24 14:31:35 -10:00
Tejun Heo
bd2d76455b sched_ext: Defer scx_hardlockup() out of NMI
scx_hardlockup() runs from NMI and eventually calls scx_claim_exit(),
which takes scx_sched_lock. scx_sched_lock isn't NMI-safe and grabbing
it from NMI context can lead to deadlocks.

The hardlockup handler is best-effort recovery and the disable path it
triggers runs off of irq_work anyway. Move the handle_lockup() call into
an irq_work so it runs in IRQ context.

Fixes: ebeca1f930 ("sched_ext: Introduce cgroup sub-sched support")
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-04-24 14:13:22 -10:00
Linus Torvalds
27d128c1cf ring-buffer fix for 7.1:
- Fix accounting of persistent ring buffer rewind
 
   On boot up, the head page is moved back to the earliest point of
   the saved ring buffer. This is because the ring buffer being read by
   user space on a crash may not save the part it read. Rewinding the head
   page back to the earliest saved position helps keep those events from
   being lost.
 
   The number of events is also read during boot up and displayed in the
   stats file in the tracefs directory. It's also used for other accounting
   as well. On boot up, the "reader page" is accounted for but a rewind may
   put it back into the buffer and then the reader page may be accounted
   for again.
 
   Save off the original reader page and skip accounting it when scanning
   the pages in the ring buffer.
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Merge tag 'trace-ring-buffer-v7.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull ring-buffer fix from Steven Rostedt:

 - Fix accounting of persistent ring buffer rewind

   On boot up, the head page is moved back to the earliest point of the
   saved ring buffer. This is because the ring buffer being read by user
   space on a crash may not save the part it read. Rewinding the head
   page back to the earliest saved position helps keep those events from
   being lost.

   The number of events is also read during boot up and displayed in the
   stats file in the tracefs directory. It's also used for other
   accounting as well. On boot up, the "reader page" is accounted for
   but a rewind may put it back into the buffer and then the reader page
   may be accounted for again.

   Save off the original reader page and skip accounting it when
   scanning the pages in the ring buffer.

* tag 'trace-ring-buffer-v7.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Do not double count the reader_page
2026-04-24 15:17:23 -07:00
Masami Hiramatsu (Google)
92d5a60672 ring-buffer: Do not double count the reader_page
Since the cpu_buffer->reader_page is updated if there are unwound
pages. After that update, we should skip the page if it is the
original reader_page, because the original reader_page is already
checked.

Cc: stable@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Ian Rogers <irogers@google.com>
Link: https://patch.msgid.link/177701353063.2223789.1471163147644103306.stgit@mhiramat.tok.corp.google.com
Fixes: ca296d32ec ("tracing: ring_buffer: Rewind persistent ring buffer on reboot")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-04-24 15:34:39 -04:00
Richard Cheng
510a270554 sched_ext: sync disable_irq_work in bpf_scx_unreg()
When unregistered my self-written scx scheduler, the following panic
occurs.

[  229.923133] Kernel text patching generated an invalid instruction at 0xffff80009bc2c1f8!
[  229.923146] Internal error: Oops - BRK: 00000000f2000100 [#1]  SMP
[  230.077871] CPU: 48 UID: 0 PID: 1760 Comm: kworker/u583:7 Not tainted 7.0.0+ #3 PREEMPT(full)
[  230.086677] Hardware name: NVIDIA GB200 NVL/P3809-BMC, BIOS 02.05.12 20251107
[  230.093972] Workqueue: events_unbound bpf_map_free_deferred
[  230.099675] Sched_ext: invariant_0.1.0_aarch64_unknown_linux_gnu_debug (disabling), task: runnable_at=-174ms
[  230.116843] pc : 0xffff80009bc2c1f8
[  230.120406] lr : dequeue_task_scx+0x270/0x2d0
[  230.217749] Call trace:
[  230.228515]  0xffff80009bc2c1f8 (P)
[  230.232077]  dequeue_task+0x84/0x188
[  230.235728]  sched_change_begin+0x1dc/0x250
[  230.240000]  __set_cpus_allowed_ptr_locked+0x17c/0x240
[  230.245250]  __set_cpus_allowed_ptr+0x74/0xf0
[  230.249701]  ___migrate_enable+0x4c/0xa0
[  230.253707]  bpf_map_free_deferred+0x1a4/0x1b0
[  230.258246]  process_one_work+0x184/0x540
[  230.262342]  worker_thread+0x19c/0x348
[  230.266170]  kthread+0x13c/0x150
[  230.269465]  ret_from_fork+0x10/0x20
[  230.281393] Code: d4202000 d4202000 d4202000 d4202000 (d4202000)
[  230.287621] ---[ end trace 0000000000000000 ]---
[  231.160046] Kernel panic - not syncing: Oops - BRK: Fatal exception in interrupt

The root cause is that the JIT page backing ops->quiescent() is freed
before all callers of that function have stopped.

The expected ordering during teardown is:
    bitmap_zero(sch->has_op) + synchronize_rcu()
        -> guarantees no CPU will ever call sch->ops.* again
    -> only THEN free the BPF struct_ops JIT page

bpf_scx_unreg() is supposed to enforce the order, but after
commit f4a6c506d1 ("sched_ext: Always bounce scx_disable() through
irq_work"), disable_work is no longer queued directly, causing
kthread_flush_work() to be a noop. Thus, the caller drops the struct_ops
map too early and poisoned with AARCH64_BREAK_FAULT before
disable_workfn ever execute.

So the subsequent dequeue_task() still sees SCX_HAS_OP(sch, quiescent)
as true and calls ops.quiescent, which hit on the poisoned page and BRK
panic.

Add a helper scx_flush_disable_work() so the future use cases that want
to flush disable_work can use it.
Also amend the call for scx_root_enable_workfn() and
scx_sub_enable_workfn() which have similar pattern in the error path.

Fixes: f4a6c506d1 ("sched_ext: Always bounce scx_disable() through irq_work")
Signed-off-by: Richard Cheng <icheng@nvidia.com>
Reviewed-by: Andrea Righi <arighi@nvidia.com>
Reviewed-by: Cheng-Yang Chou <yphbchou0911@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-24 07:26:48 -10:00
Linus Torvalds
892c894b4b Misc locking fixes:
- Fix ww_mutex regression, which caused hangs/pauses in some DRM drivers
  - Fix rtmutex proxy-rollback bug
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-urgent-2026-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fixes from Ingo Molnar:

 - Fix ww_mutex regression, which caused hangs/pauses in some DRM drivers

 - Fix rtmutex proxy-rollback bug

* tag 'locking-urgent-2026-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/mutex: Fix ww_mutex wait_list operations
  rtmutex: Use waiter::task instead of current in remove_waiter()
2026-04-24 10:14:29 -07:00
Petr Malat
13e786b64b cgroup: Increment nr_dying_subsys_* from rmdir context
Incrementing nr_dying_subsys_* in offline_css(), which is executed by
cgroup_offline_wq worker, leads to a race where user can see the value
to be 0 if he reads cgroup.stat after calling rmdir and before the worker
executes. This makes the user wrongly expect resources released by the
removed cgroup to be available for a new assignment.

Increment nr_dying_subsys_* from kill_css(), which is called from the
cgroup_rmdir() context.

Fixes: ab03125268 ("cgroup: Show # of subsystem CSSes in cgroup.stat")
Signed-off-by: Petr Malat <oss@malat.biz>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-23 07:37:40 -10:00
zhidao su
4e3d7c89e1 sched_ext: Fix local_dsq_post_enq() to use task's scheduler in sub-sched
local_dsq_post_enq() calls call_task_dequeue() with scx_root instead of
the scheduler instance actually managing the task. When
CONFIG_EXT_SUB_SCHED is enabled, tasks may be managed by a sub-scheduler
whose ops.dequeue() callback differs from root's. Using scx_root causes
the wrong scheduler's ops.dequeue() to be consulted: sub-sched tasks
dispatched to a local DSQ via scx_bpf_dsq_move_to_local() will have
SCX_TASK_IN_CUSTODY cleared but the sub-scheduler's ops.dequeue() is
never invoked, violating the custody exit semantics.

Fix by adding a 'struct scx_sched *sch' parameter to local_dsq_post_enq()
and move_local_task_to_local_dsq(), and propagating the correct scheduler
from their callers dispatch_enqueue(), move_task_between_dsqs(), and
consume_dispatch_q().

This is consistent with dispatch_enqueue()'s non-local path which already
passes 'sch' directly to call_task_dequeue() for global/bypass DSQs.

Fixes: ebf1ccff79 ("sched_ext: Fix ops.dequeue() semantics")
Signed-off-by: zhidao su <suzhidao@xiaomi.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-23 06:36:56 -10:00
Peter Zijlstra
0adc92b910 locking/mutex: Fix ww_mutex wait_list operations
Chaitanya, John and Mikhail reported commit 25500ba7e7 ("locking/mutex:
Remove the list_head from struct mutex") wrecked ww_mutex.

Specifically there were 2 issues:

 - __ww_waiter_prev() had the termination condition wrong; it would terminate
   when the previous entry was the first, which results in a truncated
   iteration: W3, W2, (no W1).

 - __mutex_add_waiter(@pos != NULL), as used by __ww_waiter_add() /
   __ww_mutex_add_waiter(); this inserts @waiter before @pos (which is what
   list_add_tail() does). But this should then also update lock->first_waiter.

Much thanks to Prateek for spotting the __mutex_add_waiter() issue!

Fixes: 25500ba7e7 ("locking/mutex: Remove the list_head from struct mutex")
Reported-by: "Borah, Chaitanya Kumar" <chaitanya.kumar.borah@intel.com>
Closes: https://lore.kernel.org/r/af005996-05e9-4336-8450-d14ca652ba5d%40intel.com
Reported-by: John Stultz <jstultz@google.com>
Closes: https://lore.kernel.org/r/CANDhNCq%3Doizzud3hH3oqGzTrcjB8OwGeineJ3mwZuGdDWG8fRQ%40mail.gmail.com
Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Closes: https://lore.kernel.org/r/CABXGCsO5fKq2nD9nO8yO1z50ZzgCPWqueNXHANjntaswoOh2Dg@mail.gmail.com
Debugged-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Link: https://patch.msgid.link/20260422092335.GH3102924%40noisy.programming.kicks-ass.net
2026-04-23 10:05:49 +02:00
Linus Torvalds
1e18ed5727 ring-buffer fix for v7.1
- Make undefsyms_base.c into a real file
 
   The file undefsyms_base.c is used to catch any symbols used by a remote
   ring buffer that is made for use of a pKVM hypervisor. As it doesn't share
   the same text as the rest of the kernel, referencing any symbols within
   the kernel will make it fail to be built for the standalone hypervisor.
 
   A file was created by the Makefile that checked for any symbols that could
   cause issues. There's no reason to have this file created by the Makefile,
   just create it as a normal file instead.
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Merge tag 'trace-ring-buffer-v7.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull ring-buffer fix from Steven Rostedt:

 - Make undefsyms_base.c into a real file

   The file undefsyms_base.c is used to catch any symbols used by a
   remote ring buffer that is made for use of a pKVM hypervisor. As it
   doesn't share the same text as the rest of the kernel, referencing
   any symbols within the kernel will make it fail to be built for the
   standalone hypervisor.

   A file was created by the Makefile that checked for any symbols that
   could cause issues. There's no reason to have this file created by
   the Makefile, just create it as a normal file instead.

* tag 'trace-ring-buffer-v7.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Make undefsyms_base.c a first-class citizen
2026-04-22 14:47:52 -07:00
Linus Torvalds
38ee6e1fb6 kgdb patches for 7.1
Only a very small update for kgdb this cycle: a single patch from Kexin Sun
 that fixes some outdated comments.
 
 Signed-off-by: Daniel Thompson (RISCstar) <danielt@kernel.org>
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Merge tag 'kgdb-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux

Pull kgdb update from Daniel Thompson:
 "Only a very small update for kgdb this cycle: a single patch from
  Kexin Sun that fixes some outdated comments"

* tag 'kgdb-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
  kgdb: update outdated references to kgdb_wait()
2026-04-22 14:26:58 -07:00
Paolo Bonzini
5335e318ad tracing: Make undefsyms_base.c a first-class citizen
Linus points out that dumping undefsyms_base.c form the Makefile
is rather ugly, and that a much better course of action would be
to have this file as a first-class citizen in the git tree.

This allows some extra cleanup in the Makefile, and the removal of
the .gitignore file in kernel/trace.

Cc: Marc Zyngier <maz@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/CAHk-=wieqGd_XKpu8UxDoyADZx8TDe8CF3RmkUXt5N_9t5Pf_w@mail.gmail.com
Link: https://lore.kernel.org/all/20260421095446.2951646-1-maz@kernel.org/
Link: https://patch.msgid.link/20260421100455.324333-1-pbonzini@redhat.com
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-04-22 11:24:41 -04:00
Masami Hiramatsu (Google)
476c5bbae6 tracing/fprobe: Fix to unregister ftrace_ops if it is empty on module unloading
Fix fprobe to unregister ftrace_ops if corresponding type of fprobe
does not exist on the fprobe_ip_table and it is expected to be empty
when unloading modules.

Since ftrace thinks that the empty hash means everything to be traced,
if we set fprobes only on the unloaded module, all functions are traced
unexpectedly after unloading module.
e.g.

 # modprobe xt_LOG.ko
 # echo 'f:test log_tg*' > dynamic_events
 # echo 1 > events/fprobes/test/enable
 # cat enabled_functions
log_tg [xt_LOG] (1)             tramp: 0xffffffffa0004000 (fprobe_ftrace_entry+0x0/0x490) ->fprobe_ftrace_entry+0x0/0x490
log_tg_check [xt_LOG] (1)               tramp: 0xffffffffa0004000 (fprobe_ftrace_entry+0x0/0x490) ->fprobe_ftrace_entry+0x0/0x490
log_tg_destroy [xt_LOG] (1)             tramp: 0xffffffffa0004000 (fprobe_ftrace_entry+0x0/0x490) ->fprobe_ftrace_entry+0x0/0x490
 # rmmod xt_LOG
 # wc -l enabled_functions
34085 enabled_functions

Link: https://lore.kernel.org/all/177669368776.132053.10042301916765771279.stgit@mhiramat.tok.corp.google.com/

Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-04-22 09:24:13 +09:00
Kexin Sun
256e5254ef kgdb: update outdated references to kgdb_wait()
The function kgdb_wait() was folded into the static function
kgdb_cpu_enter() by commit 62fae31219 ("kgdb: eliminate
kgdb_wait(), all cpus enter the same way").  Update the four stale
references accordingly:

 - include/linux/kgdb.h and arch/x86/kernel/kgdb.c: the
   kgdb_roundup_cpus() kdoc describes what other CPUs are rounded up
   to call.  Because kgdb_cpu_enter() is static, the correct public
   entry point is kgdb_handle_exception(); also fix a pre-existing
   grammar error ("get them be" -> "get them into") and reflow the
   text.

 - kernel/debug/debug_core.c: replace with the generic description
   "the debug trap handler", since the actual entry path is
   architecture-specific.

 - kernel/debug/gdbstub.c: kgdb_cpu_enter() is correct here (it
   describes internal state, not a call target); add the missing
   parentheses.

Suggested-by: Daniel Thompson <daniel@riscstar.com>
Assisted-by: unnamed:deepseek-v3.2 coccinelle
Signed-off-by: Kexin Sun <kexinsun@smail.nju.edu.cn>
2026-04-21 16:41:54 +01:00
Masami Hiramatsu (Google)
0ac0058a74 tracing/fprobe: Check the same type fprobe on table as the unregistered one
Commit 2c67dc457b ("tracing: fprobe: optimization for entry only case")
introduced a different ftrace_ops for entry-only fprobes.

However, when unregistering an fprobe, the kernel only checks if another
fprobe exists at the same address, without checking which type of fprobe
it is.
If different fprobes are registered at the same address, the same address
will be registered in both fgraph_ops and ftrace_ops, but only one of
them will be deleted when unregistering. (the one removed first will not
be deleted from the ops).

This results in junk entries remaining in either fgraph_ops or ftrace_ops.
For example:
 =======
 cd /sys/kernel/tracing

 # 'Add entry and exit events on the same place'
 echo 'f:event1 vfs_read' >> dynamic_events
 echo 'f:event2 vfs_read%return' >> dynamic_events

 # 'Enable both of them'
 echo 1 > events/fprobes/enable
 cat enabled_functions
vfs_read (2)            ->arch_ftrace_ops_list_func+0x0/0x210

 # 'Disable and remove exit event'
 echo 0 > events/fprobes/event2/enable
 echo -:event2 >> dynamic_events

 # 'Disable and remove all events'
 echo 0 > events/fprobes/enable
 echo > dynamic_events

 # 'Add another event'
 echo 'f:event3 vfs_open%return' > dynamic_events
 cat dynamic_events
f:fprobes/event3 vfs_open%return

 echo 1 > events/fprobes/enable
 cat enabled_functions
vfs_open (1)            tramp: 0xffffffffa0001000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60    subops: {ent:fprobe_fgraph_entry+0x0/0x620 ret:fprobe_return+0x0/0x150}
vfs_read (1)            tramp: 0xffffffffa0001000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60    subops: {ent:fprobe_fgraph_entry+0x0/0x620 ret:fprobe_return+0x0/0x150}
 =======

As you can see, an entry for the vfs_read remains.

To fix this issue, when unregistering, the kernel should also check if
there is the same type of fprobes still exist at the same address, and
if not, delete its entry from either fgraph_ops or ftrace_ops.

Link: https://lore.kernel.org/all/177669367993.132053.10553046138528674802.stgit@mhiramat.tok.corp.google.com/

Fixes: 2c67dc457b ("tracing: fprobe: optimization for entry only case")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-04-22 00:03:10 +09:00
Masami Hiramatsu (Google)
aa72812b49 tracing/fprobe: Avoid kcalloc() in rcu_read_lock section
fprobe_remove_node_in_module() is called under RCU read locked, but
this invokes kcalloc() if there are more than 8 fprobes installed
on the module. Sashiko warns it because kcalloc() can sleep [1].

 [1] https://sashiko.dev/#/patchset/177552432201.853249.5125045538812833325.stgit%40mhiramat.tok.corp.google.com

To fix this issue, expand the batch size to 128 and do not expand
the fprobe_addr_list, but just cancel walking on fprobe_ip_table,
update fgraph/ftrace_ops and retry the loop again.

Link: https://lore.kernel.org/all/177669367206.132053.1493637946869032744.stgit@mhiramat.tok.corp.google.com/

Fixes: 0de4c70d04 ("tracing: fprobe: use rhltable for fprobe_ip_table")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-04-22 00:02:59 +09:00
Masami Hiramatsu (Google)
845947aca6 tracing/fprobe: Remove fprobe from hash in failure path
When register_fprobe_ips() fails, it tries to remove a list of
fprobe_hash_node from fprobe_ip_table, but it missed to remove
fprobe itself from fprobe_table. Moreover, when removing
the fprobe_hash_node which is added to rhltable once, it must
use kfree_rcu() after removing from rhltable.

To fix these issues, this reuses unregister_fprobe() internal
code to rollback the half-way registered fprobe.

Link: https://lore.kernel.org/all/177669366417.132053.17874946321744910456.stgit@mhiramat.tok.corp.google.com/

Fixes: 4346ba1604 ("fprobe: Rewrite fprobe on function-graph tracer")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-04-21 23:59:57 +09:00
Masami Hiramatsu (Google)
1aec9e5c3e tracing/fprobe: Unregister fprobe even if memory allocation fails
unregister_fprobe() can fail under memory pressure because of memory
allocation failure, but this maybe called from module unloading, and
usually there is no way to retry it. Moreover. trace_fprobe does not
check the return value.

To fix this problem, unregister fprobe and fprobe_hash_node even if
working memory allocation fails.
Anyway, if the last fprobe is removed, the filter will be freed.

Link: https://lore.kernel.org/all/177669365629.132053.8433032896213721288.stgit@mhiramat.tok.corp.google.com/

Fixes: 4346ba1604 ("fprobe: Rewrite fprobe on function-graph tracer")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-04-21 23:59:39 +09:00
Masami Hiramatsu (Google)
6ad51ada17 tracing/fprobe: Reject registration of a registered fprobe before init
Reject registration of a registered fprobe which is on the fprobe
hash table before initializing fprobe.
The add_fprobe_hash() checks this re-register fprobe, but since
fprobe_init() clears hlist_array field, it is too late to check it.
It has to check the re-registration before touncing fprobe.

Link: https://lore.kernel.org/all/177669364845.132053.18375367916162315835.stgit@mhiramat.tok.corp.google.com/

Fixes: 4346ba1604 ("fprobe: Rewrite fprobe on function-graph tracer")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-04-21 23:59:29 +09:00
Linus Torvalds
b4e07588e7 tracing: tell git to ignore the generated 'undefsyms_base.c' file
This odd file was added to automatically figure out tool-generated
symbols.

Honestly, it *should* have been just a real honest-to-goodness regular
file in git, instead of having strange code to generate it in the
Makefile, but that is not how that silly thing works.  So now we need to
ignore it explicitly.

Fixes: 1211907ac0 ("tracing: Generate undef symbols allowlist for simple_ring_buffer")
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Steven Rostedt (Google) <rostedt@goodmis.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-04-20 17:25:56 -07:00
Linus Torvalds
b66cb4f156 printk changes for 7.1
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Merge tag 'printk-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk updates from Petr Mladek:

 - Fix printk ring buffer initialization and sanity checks

 - Workaround printf kunit test compilation with gcc < 12.1

 - Add IPv6 address printf format tests

 - Misc code and documentation cleanup

* tag 'printk-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printf: Compile the kunit test with DISABLE_BRANCH_PROFILING DISABLE_BRANCH_PROFILING
  lib/vsprintf: use bool for local decode variable
  lib/hexdump: print_hex_dump_bytes() calls print_hex_dump_debug()
  printk: ringbuffer: fix errors in comments
  printk_ringbuffer: Add sanity check for 0-size data
  printk_ringbuffer: Fix get_data() size sanity check
  printf: add IPv6 address format tests
  printk: Fix _DESCS_COUNT type for 64-bit systems
2026-04-20 15:42:18 -07:00
Linus Torvalds
ccbc9fdb32 Fix timer stalls caused by incorrect handling of
the dev->next_event_forced flag.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'timers-urgent-2026-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Ingo Molnar:
 "Fix timer stalls caused by incorrect handling of the
  dev->next_event_forced flag"

* tag 'timers-urgent-2026-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clockevents: Add missing resets of the next_event_forced flag
2026-04-20 15:30:08 -07:00
Keenan Dong
3bfdc63936 rtmutex: Use waiter::task instead of current in remove_waiter()
remove_waiter() is used by the slowlock paths, but it is also used for
proxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from
futex_requeue().

In the latter case waiter::task is not current, but remove_waiter()
operates on current for the dequeue operation. That results in several
problems:

  1) the rbtree dequeue happens without waiter::task::pi_lock being held

  2) the waiter task's pi_blocked_on state is not cleared, which leaves a
     dangling pointer primed for UAF around.

  3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter
     task

Use waiter::task instead of current in all related operations in
remove_waiter() to cure those problems.

[ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the
  	changelog ]

Fixes: 8161239a8b ("rtmutex: Simplify PI algorithm and make highest prio task get lock")
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Keenan Dong <keenanat2000@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
2026-04-21 00:22:31 +02:00
Cheng-Yang Chou
2d2b026c3e sched_ext: Deny SCX kfuncs to non-SCX struct_ops programs
scx_kfunc_context_filter() currently allows non-SCX struct_ops programs
(e.g. tcp_congestion_ops) to call SCX unlocked kfuncs. This is wrong
for two reasons:

- It is semantically incorrect: a TCP congestion control program has no
  business calling SCX kfuncs such as scx_bpf_kick_cpu().

- With CONFIG_EXT_SUB_SCHED=y, kfuncs like scx_bpf_kick_cpu() call
  scx_prog_sched(aux), which invokes bpf_prog_get_assoc_struct_ops(aux)
  and casts the result to struct sched_ext_ops * before reading ops->priv.
  For a non-SCX struct_ops program the returned pointer is the kdata of
  that struct_ops type, which is far smaller than sched_ext_ops, making
  the read an out-of-bounds access (confirmed with KASAN).

Extend the filter to cover scx_kfunc_set_any and scx_kfunc_set_idle as
well, and deny all SCX kfuncs for any struct_ops program that is not the
SCX struct_ops. This addresses both issues: the semantic contract is
enforced at the verifier level, and the runtime out-of-bounds access
becomes unreachable.

Fixes: d1d3c1c6ae ("sched_ext: Add verifier-time kfunc context filter")
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Cheng-Yang Chou <yphbchou0911@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-20 07:57:29 -10:00
Petr Mladek
add9d911be Merge branch 'rework/prb-fixes' into for-linus 2026-04-20 13:42:01 +02:00
Tejun Heo
87019cb6c2 sched_ext: Mark scx_sched_hash insecure_elasticity
scx_sched_hash is inserted into under scx_sched_lock (raw_spinlock_irq)
in scx_link_sched(). rhashtable's sync grow path calls get_random_u32()
and does a GFP_ATOMIC allocation; both acquire regular spinlocks, which
is unsafe under raw_spinlock_t. Set insecure_elasticity to skip the
sync grow.

v2:
- Dropped dsq_hash changes. Insertion is not under raw_spin_lock.

- Switched from no_sync_grow flag to insecure_elasticity.

Fixes: 25037af712 ("sched_ext: Add rhashtable lookup for sub-schedulers")
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-19 05:47:28 -10:00
Linus Torvalds
40735a683b mm.git review status for linus..mm-stable
Everything:
 
 Total patches:       121
 Reviews/patch:       2.11
 Reviewed rate:       90%
 
 Excluding DAMON:
 
 Total patches:       113
 Reviews/patch:       2.25
 Reviewed rate:       96%
 
 - The 33 patch series "Eliminate Dying Memory Cgroup" from Qi Zheng and
   Muchun Song addresses the longstanding "dying memcg problem".  A
   situation wherein a no-longer-used memory control group will hang around
   for an extended period pointlessly consuming memory.  The [0/N]
   changelog has a good overview of this work.
 
 - The 3 patch series "fix unexpected type conversions and potential
   overflows" from Qi Zheng fixes a couple of potential 32-bit/64-bit
   issues which were identified during review of the "Eliminate Dying
   Memory Cgroup" series.
 
 - The 6 patch series "kho: history: track previous kernel version and
   kexec boot count" from Breno Leitao uses Kexec Handover (KHO) to pass
   the previous kernel's version string and the number of kexec reboots
   since the last cold boot to the next kernel, and prints it at boot time.
 
 - The 4 patch series "liveupdate: prevent double preservation" from
   Pasha Tatashin teaches LUO to avoid managing the same file across
   different active sessions.
 
 - The 10 patch series "liveupdate: Fix module unloading and unregister
   API" from Pasha Tatashin addresses an issue with how LUO handles module
   reference counting and unregistration during module unloading.
 
 - The 2 patch series "zswap pool per-CPU acomp_ctx simplifications" from
   Kanchana Sridhar simplifies and cleans up the zswap crypto compression
   handling and improves the lifecycle management of zswap pool's per-CPU
   acomp_ctx resources.
 
 - The 2 patch series "mm/damon/core: fix damon_call()/damos_walk() vs
   kdmond exit race" from SeongJae Park addresses unlikely but possible
   leaks and deadlocks in damon_call() and damon_walk().
 
 - The 2 patch series "mm/damon/core: validate damos_quota_goal->nid"
   from SeongJae Park fixes a couple of root-only wild pointer
   dereferences.
 
 - The 2 patch series "Docs/admin-guide/mm/damon: warn commit_inputs vs
   other params race" from SeongJae Park updates the DAMON documentation to
   warn operators about potential races which can occur if the
   commit_inputs parameter is altered at the wrong time.
 
 - The 3 patch series "Minor hmm_test fixes and cleanups" from Alistair
   Popple implements two bugfixes a cleanup for the HMM kernel selftests.
 
 - The 6 patch series "Modify memfd_luo code" from Chenghao Duan provides
   cleanups, simplifications and speedups in the memfd_lou code.
 
 - The 4 patch series "mm, kvm: allow uffd support in guest_memfd" from
   Mike Rapoport enables support for userfaultfd in guest_memfd.
 
 - The 6 patch series "selftests/mm: skip several tests when thp is not
   available" from Chunyu Hu fixes several issues in the selftests code
   which were causing breakage when the tests were run on CONFIG_THP=n
   kernels.
 
 - The 2 patch series "mm/mprotect: micro-optimization work" from Pedro
   Falcato implements a couple of nice speedups for mprotect().
 
 - The 3 patch series "MAINTAINERS: update KHO and LIVE UPDATE entries"
   from Pratyush Yadav reflects upcoming changes in the maintenance of KHO,
   LUO, memfd_luo, kexec, crash, kdump and probably other kexec-based
   things - they are being moved out of mm.git and into a new git tree.
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Merge tag 'mm-stable-2026-04-18-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull more MM updates from Andrew Morton:

 - "Eliminate Dying Memory Cgroup" (Qi Zheng and Muchun Song)

   Address the longstanding "dying memcg problem". A situation wherein a
   no-longer-used memory control group will hang around for an extended
   period pointlessly consuming memory

 - "fix unexpected type conversions and potential overflows" (Qi Zheng)

   Fix a couple of potential 32-bit/64-bit issues which were identified
   during review of the "Eliminate Dying Memory Cgroup" series

 - "kho: history: track previous kernel version and kexec boot count"
   (Breno Leitao)

   Use Kexec Handover (KHO) to pass the previous kernel's version string
   and the number of kexec reboots since the last cold boot to the next
   kernel, and print it at boot time

 - "liveupdate: prevent double preservation" (Pasha Tatashin)

   Teach LUO to avoid managing the same file across different active
   sessions

 - "liveupdate: Fix module unloading and unregister API" (Pasha
   Tatashin)

   Address an issue with how LUO handles module reference counting and
   unregistration during module unloading

 - "zswap pool per-CPU acomp_ctx simplifications" (Kanchana Sridhar)

   Simplify and clean up the zswap crypto compression handling and
   improve the lifecycle management of zswap pool's per-CPU acomp_ctx
   resources

 - "mm/damon/core: fix damon_call()/damos_walk() vs kdmond exit race"
   (SeongJae Park)

   Address unlikely but possible leaks and deadlocks in damon_call() and
   damon_walk()

 - "mm/damon/core: validate damos_quota_goal->nid" (SeongJae Park)

   Fix a couple of root-only wild pointer dereferences

 - "Docs/admin-guide/mm/damon: warn commit_inputs vs other params race"
   (SeongJae Park)

   Update the DAMON documentation to warn operators about potential
   races which can occur if the commit_inputs parameter is altered at
   the wrong time

 - "Minor hmm_test fixes and cleanups" (Alistair Popple)

   Bugfixes and a cleanup for the HMM kernel selftests

 - "Modify memfd_luo code" (Chenghao Duan)

   Cleanups, simplifications and speedups to the memfd_lou code

 - "mm, kvm: allow uffd support in guest_memfd" (Mike Rapoport)

   Support for userfaultfd in guest_memfd

 - "selftests/mm: skip several tests when thp is not available" (Chunyu
   Hu)

   Fix several issues in the selftests code which were causing breakage
   when the tests were run on CONFIG_THP=n kernels

 - "mm/mprotect: micro-optimization work" (Pedro Falcato)

   A couple of nice speedups for mprotect()

 - "MAINTAINERS: update KHO and LIVE UPDATE entries" (Pratyush Yadav)

   Document upcoming changes in the maintenance of KHO, LUO, memfd_luo,
   kexec, crash, kdump and probably other kexec-based things - they are
   being moved out of mm.git and into a new git tree

* tag 'mm-stable-2026-04-18-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (121 commits)
  MAINTAINERS: add page cache reviewer
  mm/vmscan: avoid false-positive -Wuninitialized warning
  MAINTAINERS: update Dave's kdump reviewer email address
  MAINTAINERS: drop include/linux/liveupdate from LIVE UPDATE
  MAINTAINERS: drop include/linux/kho/abi/ from KHO
  MAINTAINERS: update KHO and LIVE UPDATE maintainers
  MAINTAINERS: update kexec/kdump maintainers entries
  mm/migrate_device: remove dead migration entry check in migrate_vma_collect_huge_pmd()
  selftests: mm: skip charge_reserved_hugetlb without killall
  userfaultfd: allow registration of ranges below mmap_min_addr
  mm/vmstat: fix vmstat_shepherd double-scheduling vmstat_update
  mm/hugetlb: fix early boot crash on parameters without '=' separator
  zram: reject unrecognized type= values in recompress_store()
  docs: proc: document ProtectionKey in smaps
  mm/mprotect: special-case small folios when applying permissions
  mm/mprotect: move softleaf code out of the main function
  mm: remove '!root_reclaim' checking in should_abort_scan()
  mm/sparse: fix comment for section map alignment
  mm/page_io: use sio->len for PSWPIN accounting in sio_read_complete()
  selftests/mm: transhuge_stress: skip the test when thp not available
  ...
2026-04-19 08:01:17 -07:00
Linus Torvalds
9055c64567 memblock: updates for 7.0-rc1
* improve debugability of reserve_mem kernel parameter handling with print
   outs in case of a failure and debugfs info showing what was actually
   reserved
 * Make memblock_free_late() and free_reserved_area() use the same core
   logic for freeing the memory to buddy and ensure it takes care of
   updating memblock arrays when ARCH_KEEP_MEMBLOCK is enabled.
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Merge tag 'memblock-v7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock

Pull memblock updates from Mike Rapoport:

 - improve debuggability of reserve_mem kernel parameter handling with
   print outs in case of a failure and debugfs info showing what was
   actually reserved

 - Make memblock_free_late() and free_reserved_area() use the same core
   logic for freeing the memory to buddy and ensure it takes care of
   updating memblock arrays when ARCH_KEEP_MEMBLOCK is enabled.

* tag 'memblock-v7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock:
  x86/alternative: delay freeing of smp_locks section
  memblock: warn when freeing reserved memory before memory map is initialized
  memblock, treewide: make memblock_free() handle late freeing
  memblock: make free_reserved_area() update memblock if ARCH_KEEP_MEMBLOCK=y
  memblock: extract page freeing from free_reserved_area() into a helper
  memblock: make free_reserved_area() more robust
  mm: move free_reserved_area() to mm/memblock.c
  powerpc: opal-core: pair alloc_pages_exact() with free_pages_exact()
  powerpc: fadump: pair alloc_pages_exact() with free_pages_exact()
  memblock: reserve_mem: fix end caclulation in reserve_mem_release_by_name()
  memblock: move reserve_bootmem_range() to memblock.c and make it static
  memblock: Add reserve_mem debugfs info
  memblock: Print out errors on reserve_mem parser
2026-04-18 11:29:14 -07:00
Pasha Tatashin
68750e820b liveupdate: defer file handler module refcounting to active sessions
Stop pinning modules indefinitely upon file handler registration. 
Instead, dynamically increment the module reference count only when a live
update session actively uses the file handler (e.g., during preservation
or deserialization), and release it when the session ends.

This allows modules providing live update handlers to be gracefully
unloaded when no live update is in progress.

Link: https://lore.kernel.org/20260327033335.696621-11-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:50 -07:00
Pasha Tatashin
2ab7207e7e liveupdate: make unregister functions return void
Change liveupdate_unregister_file_handler and liveupdate_unregister_flb to
return void instead of an error code.  This follows the design principle
that unregistration during module unload should not fail, as the unload
cannot be stopped at that point.

Link: https://lore.kernel.org/20260327033335.696621-10-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:50 -07:00
Pasha Tatashin
074488008d liveupdate: remove liveupdate_test_unregister()
Now that file handler unregistration automatically unregisters all
associated file handlers (FLBs), the liveupdate_test_unregister() function
is no longer needed.  Remove it along with its usages and declarations.

Link: https://lore.kernel.org/20260327033335.696621-9-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:50 -07:00
Pasha Tatashin
5ee1c7d641 liveupdate: auto unregister FLBs on file handler unregistration
To ensure that unregistration is always successful and doesn't leave
dangling resources, introduce auto-unregistration of FLBs: when a file
handler is unregistered, all FLBs associated with it are automatically
unregistered.

Introduce a new helper luo_flb_unregister_all() which unregisters all FLBs
linked to the given file handler.

Link: https://lore.kernel.org/20260327033335.696621-8-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:50 -07:00
Pasha Tatashin
118c390824 liveupdate: remove luo_session_quiesce()
Now that FLB module references are handled dynamically during active
sessions, we can safely remove the luo_session_quiesce() and
luo_session_resume() mechanism.

Link: https://lore.kernel.org/20260327033335.696621-7-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:50 -07:00
Pasha Tatashin
76be9983df liveupdate: defer FLB module refcounting to active sessions
Stop pinning modules indefinitely upon FLB registration.  Instead,
dynamically take a module reference when the FLB is actively used in a
session (e.g., during preserve and retrieve) and release it when the
session concludes.

This allows modules providing FLB operations to be cleanly unloaded when
not in active use by the live update orchestrator.

Link: https://lore.kernel.org/20260327033335.696621-6-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Samiullah Khawaja <skhawaja@google.com>
Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:50 -07:00
Pasha Tatashin
6b2b22f7c8 liveupdate: protect FLB lists with luo_register_rwlock
Because liveupdate FLB objects will soon drop their persistent module
references when registered, list traversals must be protected against
concurrent module unloading.

To provide this protection, utilize the global luo_register_rwlock.  It
protects the global registry of FLBs and the handler's specific list of
FLB dependencies.

Read locks are used during concurrent list traversals (e.g., during
preservation and serialization).  Write locks are taken during
registration and unregistration.

Link: https://lore.kernel.org/20260327033335.696621-5-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:49 -07:00
Pasha Tatashin
9e1e185845 liveupdate: protect file handler list with rwsem
Because liveupdate file handlers will no longer hold a module reference
when registered, we must ensure that the access to the handler list is
protected against concurrent module unloading.

Utilize the global luo_register_rwlock to protect the global registry of
file handlers.  Read locks are taken during list traversals in
luo_preserve_file() and luo_file_deserialize().  Write locks are taken
during registration and unregistration.

Link: https://lore.kernel.org/20260327033335.696621-4-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:49 -07:00
Pasha Tatashin
38fb71ace2 liveupdate: synchronize lazy initialization of FLB private state
The luo_flb_get_private() function, which is responsible for lazily
initializing the private state of FLB objects, can be called concurrently
from multiple threads.  This creates a data race on the 'initialized' flag
and can lead to multiple executions of mutex_init() and INIT_LIST_HEAD()
on the same memory.

Introduce a static spinlock (luo_flb_init_lock) local to the function to
synchronize the initialization path.  Use smp_load_acquire() and
smp_store_release() for memory ordering between the fast path and the slow
path.

Link: https://lore.kernel.org/20260327033335.696621-3-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:49 -07:00
Pasha Tatashin
277f4e5e39 liveupdate: safely print untrusted strings
Patch series "liveupdate: Fix module unloading and unregister API", v3.

This patch series addresses an issue with how LUO handles module reference
counting and unregistration during a module unload (e.g., via rmmod).

Currently, modules that register live update file handlers are pinned for
the entire duration they are registered.  This prevents the modules from
being unloaded gracefully, even when no live update session is in
progress.

Furthermore, if a module is forcefully unloaded, the unregistration
functions return an error (e.g.  -EBUSY) if a session is active, which is
ignored by the kernel's module unload path, leaving dangling pointers in
the LUO global lists.

To resolve these issues, this series introduces the following changes:
1. Adds a global read-write semaphore (luo_register_rwlock) to protect
   the registration lists for both file handlers and FLBs.
2. Reduces the scope of module reference counting for file handlers and
   FLBs. Instead of pinning modules indefinitely upon registration,
   references are now taken only when they are actively used in a live
   update session (e.g., during preservation, retrieval, or
   deserialization).
3. Removes the global luo_session_quiesce() mechanism since module
   unload behavior now handles active sessions implicitly.
4. Introduces auto-unregistration of FLBs during file handler
   unregistration to prevent leaving dangling resources.
5. Changes the unregistration functions to return void instead of
   an error code.
6. Fixes a data race in luo_flb_get_private() by introducing a spinlock
   for thread-safe lazy initialization.
7. Strengthens security by using %.*s when printing untrusted deserialized
   compatible strings and session names to prevent out-of-bounds reads.


This patch (of 10):

Deserialized strings from KHO data (such as file handler compatible
strings and session names) are provided by the previous kernel and might
not be null-terminated if the data is corrupted or maliciously crafted.

When printing these strings in error messages, use the %.*s format
specifier with the maximum buffer size to prevent out-of-bounds reads into
adjacent kernel memory.

Link: https://lore.kernel.org/20260327033335.696621-1-pasha.tatashin@soleen.com
Link: https://lore.kernel.org/20260327033335.696621-2-pasha.tatashin@soleen.com
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Pratyush Yadav (Google) <pratyush@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Samiullah Khawaja <skhawaja@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:49 -07:00
Pasha Tatashin
00d0b37237 liveupdate: prevent double management of files
Patch series "liveupdate: prevent double preservation", v4.

Currently, LUO does not prevent the same file from being managed twice
across different active sessions.

Because LUO preserves files of absolutely different types: memfd, and
upcoming vfiofd [1], iommufd [2], guestmefd (and possible kvmfd/cpufd).
There is no common private data or guarantee on how to prevent that the
same file is not preserved twice beside using inode or some slower and
expensive method like hashtables.


This patch (of 4)

Currently, LUO does not prevent the same file from being managed twice
across different active sessions.

Use a global xarray luo_preserved_files to keep track of file identifiers
being preserved by LUO.  Update luo_preserve_file() to check and insert
the file identifier into this xarray when it is preserved, and erase it in
luo_file_unpreserve_files() when it is released.

To allow handlers to define what constitutes a "unique" file (e.g.,
different struct file objects pointing to the same hardware resource), add
a get_id() callback to struct liveupdate_file_ops.  If not provided, the
default identifier is the struct file pointer itself.

This ensures that the same file (or resource) cannot be managed by
multiple sessions.  If another session attempts to preserve an already
managed file, it will now fail with -EBUSY.

Link: https://lore.kernel.org/20260326163943.574070-1-pasha.tatashin@soleen.com
Link: https://lore.kernel.org/20260326163943.574070-2-pasha.tatashin@soleen.com
Link: https://lore.kernel.org/all/20260129212510.967611-1-dmatlack@google.com [1]
Link: https://lore.kernel.org/all/20260203220948.2176157-1-skhawaja@google.com [2]
Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Samiullah Khawaja <skhawaja@google.com>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: David Matlack <dmatlack@google.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Christian Brauner <brauner@kernel.org> 
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:49 -07:00
Breno Leitao
76aa46b9e4 kho: kexec-metadata: track previous kernel chain
Use Kexec Handover (KHO) to pass the previous kernel's version string and
the number of kexec reboots since the last cold boot to the next kernel,
and print it at boot time.

Example output:
    [    0.000000] KHO: exec from: 6.19.0-rc4-next-20260107 (count 1)

Motivation
==========

Bugs that only reproduce when kexecing from specific kernel versions are
difficult to diagnose.  These issues occur when a buggy kernel kexecs into
a new kernel, with the bug manifesting only in the second kernel.

Recent examples include the following commits:

 * commit eb22663125 ("x86/boot: Fix page table access in
   5-level to 4-level paging transition")
 * commit 77d48d39e9 ("efistub/tpm: Use ACPI reclaim memory
   for event log to avoid corruption")
 * commit 64b45dd46e ("x86/efi: skip memattr table on kexec
   boot")

As kexec-based reboots become more common, these version-dependent bugs
are appearing more frequently.  At scale, correlating crashes to the
previous kernel version is challenging, especially when issues only occur
in specific transition scenarios.

Implementation
==============

The kexec metadata is stored as a plain C struct (struct
kho_kexec_metadata) rather than FDT format, for simplicity and direct
field access.  It is registered via kho_add_subtree() as a separate
subtree, keeping it independent from the core KHO ABI.  This design
choice:

 - Keeps the core KHO ABI minimal and stable
 - Allows the metadata format to evolve independently
 - Avoids requiring version bumps for all KHO consumers (LUO, etc.)
   when the metadata format changes

The struct kho_kexec_metadata contains two fields:
 - previous_release: The kernel version that initiated the kexec
 - kexec_count: Number of kexec boots since last cold boot

On cold boot, kexec_count starts at 0 and increments with each kexec.  The
count helps identify issues that only manifest after multiple consecutive
kexec reboots.

[leitao@debian.org: call kho_kexec_metadata_init() for both boot paths]
  Link: https://lore.kernel.org/all/20260309-kho-v8-5-c3abcf4ac750@debian.org/ [1]
  Link: https://lore.kernel.org/20260409-kho_fix_merge_issue-v1-1-710c84ceaa85@debian.org
Link: https://lore.kernel.org/20260316-kho-v9-5-ed6dcd951988@debian.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:48 -07:00
Breno Leitao
062dd306d9 kho: fix kho_in_debugfs_init() to handle non-FDT blobs
kho_in_debugfs_init() calls fdt_totalsize() to determine blob sizes, which
assumes all blobs are FDTs.  This breaks for non-FDT blobs like struct
kho_kexec_metadata.

Fix this by reading the "blob-size" property from the FDT (persisted by
kho_add_subtree()) instead of calling fdt_totalsize().  Also rename local
variables from fdt_phys/sub_fdt to blob_phys/blob for consistency with the
non-FDT-specific naming.

Link: https://lore.kernel.org/20260316-kho-v9-4-ed6dcd951988@debian.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:48 -07:00
Breno Leitao
85e4139282 kho: persist blob size in KHO FDT
kho_add_subtree() accepts a size parameter but only forwards it to
debugfs.  The size is not persisted in the KHO FDT, so it is lost across
kexec.  This makes it impossible for the incoming kernel to determine the
blob size without understanding the blob format.

Store the blob size as a "blob-size" property in the KHO FDT alongside the
"preserved-data" physical address.  This allows the receiving kernel to
recover the size for any blob regardless of format.

Also extend kho_retrieve_subtree() with an optional size output parameter
so callers can learn the blob size without needing to understand the blob
format.  Update all callers to pass NULL for the new parameter.

Link: https://lore.kernel.org/20260316-kho-v9-3-ed6dcd951988@debian.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:48 -07:00
Breno Leitao
4916ae3867 kho: rename fdt parameter to blob in kho_add/remove_subtree()
Since kho_add_subtree() now accepts arbitrary data blobs (not just FDTs),
rename the parameter from 'fdt' to 'blob' to better reflect its purpose. 
Apply the same rename to kho_remove_subtree() for consistency.

Also rename kho_debugfs_fdt_add() and kho_debugfs_fdt_remove() to
kho_debugfs_blob_add() and kho_debugfs_blob_remove() respectively, with
the same parameter rename from 'fdt' to 'blob'.

Link: https://lore.kernel.org/20260316-kho-v9-2-ed6dcd951988@debian.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:48 -07:00
Breno Leitao
d9e4142e76 kho: add size parameter to kho_add_subtree()
Patch series "kho: history: track previous kernel version and kexec boot
count", v9.

Use Kexec Handover (KHO) to pass the previous kernel's version string and
the number of kexec reboots since the last cold boot to the next kernel,
and print it at boot time.

Example
=======
	[    0.000000] Linux version 6.19.0-rc3-upstream-00047-ge5d992347849
	...
	[    0.000000] KHO: exec from: 6.19.0-rc4-next-20260107upstream-00004-g3071b0dc4498 (count 1)

Motivation
==========

Bugs that only reproduce when kexecing from specific kernel versions are
difficult to diagnose.  These issues occur when a buggy kernel kexecs into
a new kernel, with the bug manifesting only in the second kernel.

Recent examples include:

 * eb22663125 ("x86/boot: Fix page table access in 5-level to 4-level paging transition")
 * 77d48d39e9 ("efistub/tpm: Use ACPI reclaim memory for event log to avoid corruption")
 * 64b45dd46e ("x86/efi: skip memattr table on kexec boot")

As kexec-based reboots become more common, these version-dependent bugs
are appearing more frequently.  At scale, correlating crashes to the
previous kernel version is challenging, especially when issues only occur
in specific transition scenarios.

Some bugs manifest only after multiple consecutive kexec reboots. 
Tracking the kexec count helps identify these cases (this metric is
already used by live update sub-system).

KHO provides a reliable mechanism to pass information between kernels.  By
carrying the previous kernel's release string and kexec count forward, we
can print this context at boot time to aid debugging.

The goal of this feature is to have this information being printed in
early boot, so, users can trace back kernel releases in kexec.  Systemd is
not helpful because we cannot assume that the previous kernel has systemd
or even write access to the disk (common when using Linux as bootloaders)


This patch (of 6):

kho_add_subtree() assumes the fdt argument is always an FDT and calls
fdt_totalsize() on it in the debugfs code path.  This assumption will
break if a caller passes arbitrary data instead of an FDT.

When CONFIG_KEXEC_HANDOVER_DEBUGFS is enabled, kho_debugfs_fdt_add() calls
__kho_debugfs_fdt_add(), which executes:

    f->wrapper.size = fdt_totalsize(fdt);

Fix this by adding an explicit size parameter to kho_add_subtree() so
callers specify the blob size.  This allows subtrees to contain arbitrary
data formats, not just FDTs.  Update all callers:

  - memblock.c: use fdt_totalsize(fdt)
  - luo_core.c: use fdt_totalsize(fdt_out)
  - test_kho.c: use fdt_totalsize()
  - kexec_handover.c (root fdt): use fdt_totalsize(kho_out.fdt)

Also update __kho_debugfs_fdt_add() to receive the size explicitly instead
of computing it internally via fdt_totalsize().  In kho_in_debugfs_init(),
pass fdt_totalsize() for the root FDT and sub-blobs since all current
users are FDTs.  A subsequent patch will persist the size in the KHO FDT
so the incoming side can handle non-FDT blobs correctly.

Link: https://lore.kernel.org/20260323110747.193569-1-duanchenghao@kylinos.cn
Link: https://lore.kernel.org/20260316-kho-v9-1-ed6dcd951988@debian.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Suggested-by: Pratyush Yadav <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:48 -07:00
Qi Zheng
8285917d6f mm: memcontrol: prepare for reparenting non-hierarchical stats
To resolve the dying memcg issue, we need to reparent LRU folios of child
memcg to its parent memcg.  This could cause problems for non-hierarchical
stats.

As Yosry Ahmed pointed out:

In short, if memory is charged to a dying cgroup at the time of
reparenting, when the memory gets uncharged the stats updates will occur
at the parent. This will update both hierarchical and non-hierarchical
stats of the parent, which would corrupt the parent's non-hierarchical
stats (because those counters were never incremented when the memory was
charged).

Now we have the following two types of non-hierarchical stats, and they
are only used in CONFIG_MEMCG_V1:

a. memcg->vmstats->state_local[i]
b. pn->lruvec_stats->state_local[i]

To ensure that these non-hierarchical stats work properly, we need to
reparent these non-hierarchical stats after reparenting LRU folios. To
this end, this commit makes the following preparations:

1. implement reparent_state_local() to reparent non-hierarchical stats
2. make css_killed_work_fn() to be called in rcu work, and implement
   get_non_dying_memcg_start() and get_non_dying_memcg_end() to avoid race
   between mod_memcg_state()/mod_memcg_lruvec_state()
   and reparent_state_local()

Link: https://lore.kernel.org/e862995c45a7101a541284b6ebee5e5c32c89066.1772711148.git.zhengqi.arch@bytedance.com
Co-developed-by: Yosry Ahmed <yosry@kernel.org>
Signed-off-by: Yosry Ahmed <yosry@kernel.org>
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Allen Pais <apais@linux.microsoft.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chen Ridong <chenridong@huawei.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Imran Khan <imran.f.khan@oracle.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-18 00:10:47 -07:00
Linus Torvalds
eb0d6d97c2 bpf-fixes
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Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Pull bpf fixes from Alexei Starovoitov:
 "Most of the diff stat comes from Xu Kuohai's fix to emit ENDBR/BTI,
  since all JITs had to be touched to move constant blinding out and
  pass bpf_verifier_env in.

   - Fix use-after-free in arena_vm_close on fork (Alexei Starovoitov)

   - Dissociate struct_ops program with map if map_update fails (Amery
     Hung)

   - Fix out-of-range and off-by-one bugs in arm64 JIT (Daniel Borkmann)

   - Fix precedence bug in convert_bpf_ld_abs alignment check (Daniel
     Borkmann)

   - Fix arg tracking for imprecise/multi-offset in BPF_ST/STX insns
     (Eduard Zingerman)

   - Copy token from main to subprogs to fix missing kallsyms (Eduard
     Zingerman)

   - Prevent double close and leak of btf objects in libbpf (Jiri Olsa)

   - Fix af_unix null-ptr-deref in sockmap (Michal Luczaj)

   - Fix NULL deref in map_kptr_match_type for scalar regs (Mykyta
     Yatsenko)

   - Avoid unnecessary IPIs. Remove redundant bpf_flush_icache() in
     arm64 and riscv JITs (Puranjay Mohan)

   - Fix out of bounds access. Validate node_id in arena_alloc_pages()
     (Puranjay Mohan)

   - Reject BPF-to-BPF calls and callbacks in arm32 JIT (Puranjay Mohan)

   - Refactor all JITs to pass bpf_verifier_env to emit ENDBR/BTI for
     indirect jump targets on x86-64, arm64 JITs (Xu Kuohai)

   - Allow UTF-8 literals in bpf_bprintf_prepare() (Yihan Ding)"

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (32 commits)
  bpf, arm32: Reject BPF-to-BPF calls and callbacks in the JIT
  bpf: Dissociate struct_ops program with map if map_update fails
  bpf: Validate node_id in arena_alloc_pages()
  libbpf: Prevent double close and leak of btf objects
  selftests/bpf: cover UTF-8 trace_printk output
  bpf: allow UTF-8 literals in bpf_bprintf_prepare()
  selftests/bpf: Reject scalar store into kptr slot
  bpf: Fix NULL deref in map_kptr_match_type for scalar regs
  bpf: Fix precedence bug in convert_bpf_ld_abs alignment check
  bpf, arm64: Emit BTI for indirect jump target
  bpf, x86: Emit ENDBR for indirect jump targets
  bpf: Add helper to detect indirect jump targets
  bpf: Pass bpf_verifier_env to JIT
  bpf: Move constants blinding out of arch-specific JITs
  bpf, sockmap: Take state lock for af_unix iter
  bpf, sockmap: Fix af_unix null-ptr-deref in proto update
  selftests/bpf: Extend bpf_iter_unix to attempt deadlocking
  bpf, sockmap: Fix af_unix iter deadlock
  bpf, sockmap: Annotate af_unix sock:: Sk_state data-races
  selftests/bpf: verify kallsyms entries for token-loaded subprograms
  ...
2026-04-17 15:58:22 -07:00
Amery Hung
f75aeb2de8 bpf: Dissociate struct_ops program with map if map_update fails
Currently, when bpf_struct_ops_map_update_elem() fails, the programs'
st_ops_assoc will remain set. They may become dangling pointers if the
map is freed later, but they will never be dereferenced since the
struct_ops attachment did not succeed. However, if one of the programs
is subsequently attached as part of another struct_ops map, its
st_ops_assoc will be poisoned even though its old st_ops_assoc was stale
from a failed attachment.

Fix the spurious poisoned st_ops_assoc by dissociating struct_ops
programs with a map if the attachment fails. Move
bpf_prog_assoc_struct_ops() to after *plink++ to make sure
bpf_prog_disassoc_struct_ops() will not miss a program when iterating
st_map->links.

Note that, dissociating a program from a map requires some attention as
it must not reset a poisoned st_ops_assoc or a st_ops_assoc pointing to
another map. The former is already guarded in
bpf_prog_disassoc_struct_ops(). The latter also will not happen since
st_ops_assoc of programs in st_map->links are set by
bpf_prog_assoc_struct_ops(), which can only be poisoned or pointing to
the current map.

Signed-off-by: Amery Hung <ameryhung@gmail.com>
Link: https://lore.kernel.org/r/20260417174900.2895486-1-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-17 12:04:14 -07:00
Guopeng Zhang
41d701ddc3 cgroup/cpuset: record DL BW alloc CPU for attach rollback
cpuset_can_attach() allocates DL bandwidth only when migrating
deadline tasks to a disjoint CPU mask, but cpuset_cancel_attach()
rolls back based only on nr_migrate_dl_tasks. This makes the DL
bandwidth alloc/free paths asymmetric: rollback can call dl_bw_free()
even when no dl_bw_alloc() was done.

Rollback also needs to undo the reservation against the same CPU/root
domain that was charged. Record the CPU used by dl_bw_alloc() and use
that state in cpuset_cancel_attach(). If no allocation happened,
dl_bw_cpu stays at -1 and rollback skips dl_bw_free(). If allocation
did happen, bandwidth is returned to the same CPU/root domain.

Successful attach paths are unchanged. This only fixes failed attach
rollback accounting.

Fixes: 2ef269ef1a ("cgroup/cpuset: Free DL BW in case can_attach() fails")
Signed-off-by: Guopeng Zhang <zhangguopeng@kylinos.cn>
Reviewed-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-17 08:57:37 -10:00
Linus Torvalds
87768582a4 dma-mapping updates for Linux 7.0:
- added support for batched cache sync, what improves performance of
   dma_map/unmap_sg() operations on ARM64 architecture (Barry Song)
 
 - introduced DMA_ATTR_CC_SHARED attribute for explicitly shared memory
   used in confidential computing (Jiri Pirko)
 
 - refactored spaghetti-like code in drivers/of/of_reserved_mem.c and its
   clients (Marek Szyprowski, shared branch with device-tree updates to
   avoid merge conflicts)
 
 - prepared Contiguous Memory Allocator related code for making dma-buf
   drivers modularized (Maxime Ripard)
 
 - added support for benchmarking dma_map_sg() calls to tools/dma utility
   (Qinxin Xia)
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Merge tag 'dma-mapping-7.1-2026-04-16' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux

Pull dma-mapping updates from Marek Szyprowski:

 - added support for batched cache sync, what improves performance of
   dma_map/unmap_sg() operations on ARM64 architecture (Barry Song)

 - introduced DMA_ATTR_CC_SHARED attribute for explicitly shared memory
   used in confidential computing (Jiri Pirko)

 - refactored spaghetti-like code in drivers/of/of_reserved_mem.c and
   its clients (Marek Szyprowski, shared branch with device-tree updates
   to avoid merge conflicts)

 - prepared Contiguous Memory Allocator related code for making dma-buf
   drivers modularized (Maxime Ripard)

 - added support for benchmarking dma_map_sg() calls to tools/dma
   utility (Qinxin Xia)

* tag 'dma-mapping-7.1-2026-04-16' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: (24 commits)
  dma-buf: heaps: system: document system_cc_shared heap
  dma-buf: heaps: system: add system_cc_shared heap for explicitly shared memory
  dma-mapping: introduce DMA_ATTR_CC_SHARED for shared memory
  mm: cma: Export cma_alloc(), cma_release() and cma_get_name()
  dma: contiguous: Export dev_get_cma_area()
  dma: contiguous: Make dma_contiguous_default_area static
  dma: contiguous: Make dev_get_cma_area() a proper function
  dma: contiguous: Turn heap registration logic around
  of: reserved_mem: rework fdt_init_reserved_mem_node()
  of: reserved_mem: clarify fdt_scan_reserved_mem*() functions
  of: reserved_mem: rearrange code a bit
  of: reserved_mem: replace CMA quirks by generic methods
  of: reserved_mem: switch to ops based OF_DECLARE()
  of: reserved_mem: use -ENODEV instead of -ENOENT
  of: reserved_mem: remove fdt node from the structure
  dma-mapping: fix false kernel-doc comment marker
  dma-mapping: Support batch mode for dma_direct_{map,unmap}_sg
  dma-mapping: Separate DMA sync issuing and completion waiting
  arm64: Provide dcache_inval_poc_nosync helper
  arm64: Provide dcache_clean_poc_nosync helper
  ...
2026-04-17 11:12:42 -07:00
cuitao
c802f460dd cgroup/rdma: fix integer overflow in rdmacg_try_charge()
The expression `rpool->resources[index].usage + 1` is computed in int
arithmetic before being assigned to s64 variable `new`. When usage equals
INT_MAX (the default "max" value), the addition overflows to INT_MIN.
This negative value then passes the `new > max` check incorrectly,
allowing a charge that should be rejected and corrupting usage to
negative.

Fix by casting usage to s64 before the addition so the arithmetic is
done in 64-bit.

Fixes: 39d3e7584a ("rdmacg: Added rdma cgroup controller")
Signed-off-by: cuitao <cuitao@kylinos.cn>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-17 07:25:27 -10:00
Edward Adam Davis
a5b98009f1 sched/psi: fix race between file release and pressure write
A potential race condition exists between pressure write and cgroup file
release regarding the priv member of struct kernfs_open_file, which
triggers the uaf reported in [1].

Consider the following scenario involving execution on two separate CPUs:

   CPU0					CPU1
   ====					====
					vfs_rmdir()
					kernfs_iop_rmdir()
					cgroup_rmdir()
					cgroup_kn_lock_live()
					cgroup_destroy_locked()
					cgroup_addrm_files()
					cgroup_rm_file()
					kernfs_remove_by_name()
					kernfs_remove_by_name_ns()
 vfs_write()				__kernfs_remove()
 new_sync_write()			kernfs_drain()
 kernfs_fop_write_iter()		kernfs_drain_open_files()
 cgroup_file_write()			kernfs_release_file()
 pressure_write()			cgroup_file_release()
 ctx = of->priv;
					kfree(ctx);
 					of->priv = NULL;
					cgroup_kn_unlock()
 cgroup_kn_lock_live()
 cgroup_get(cgrp)
 cgroup_kn_unlock()
 if (ctx->psi.trigger)  // here, trigger uaf for ctx, that is of->priv

The cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards
the memory deallocation of of->priv performed within cgroup_file_release().
However, the operations involving of->priv executed within pressure_write()
are not entirely covered by the protection of cgroup_mutex. Consequently,
if the code in pressure_write(), specifically the section handling the
ctx variable executes after cgroup_file_release() has completed, a uaf
vulnerability involving of->priv is triggered.

Therefore, the issue can be resolved by extending the scope of the
cgroup_mutex lock within pressure_write() to encompass all code paths
involving of->priv, thereby properly synchronizing the race condition
occurring between cgroup_file_release() and pressure_write().

And, if an live kn lock can be successfully acquired while executing
the pressure write operation, it indicates that the cgroup deletion
process has not yet reached its final stage; consequently, the priv
pointer within open_file cannot be NULL. Therefore, the operation to
retrieve the ctx value must be moved to a point *after* the live kn
lock has been successfully acquired.

In another situation, specifically after entering cgroup_kn_lock_live()
but before acquiring cgroup_mutex, there exists a different class of
race condition:

CPU0: write memory.pressure               CPU1: write cgroup.pressure=0
===========================		  =============================

kernfs_fop_write_iter()
 kernfs_get_active_of(of)
 pressure_write()
   cgroup_kn_lock_live(memory.pressure)
     cgroup_tryget(cgrp)
     kernfs_break_active_protection(kn)
     ... blocks on cgroup_mutex

                                     	  cgroup_pressure_write()
                                     	  cgroup_kn_lock_live(cgroup.pressure)
                                     	  cgroup_file_show(memory.pressure, false)
                                     	    kernfs_show(false)
                                     	      kernfs_drain_open_files()
                                     	        cgroup_file_release(of)
                                     	          kfree(ctx)
                                     	            of->priv = NULL
                                     	  cgroup_kn_unlock()

   ... acquires cgroup_mutex
   ctx = of->priv;        // may now be NULL
   if (ctx->psi.trigger)  // NULL dereference

Consequently, there is a possibility that of->priv is NULL, the pressure
write needs to check for this.

Now that the scope of the cgroup_mutex has been expanded, the original
explicit cgroup_get/put operations are no longer necessary, this is
because acquiring/releasing the live kn lock inherently executes a
cgroup get/put operation.

[1]
BUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011
Call Trace:
 pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011
 cgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:4311
 kernfs_fop_write_iter+0x3b0/0x540 fs/kernfs/file.c:352

Allocated by task 9352:
 cgroup_file_open+0x90/0x3a0 kernel/cgroup/cgroup.c:4256
 kernfs_fop_open+0x9eb/0xcb0 fs/kernfs/file.c:724
 do_dentry_open+0x83d/0x13e0 fs/open.c:949

Freed by task 9353:
 cgroup_file_release+0xd6/0x100 kernel/cgroup/cgroup.c:4283
 kernfs_release_file fs/kernfs/file.c:764 [inline]
 kernfs_drain_open_files+0x392/0x720 fs/kernfs/file.c:834
 kernfs_drain+0x470/0x600 fs/kernfs/dir.c:525

Fixes: 0e94682b73 ("psi: introduce psi monitor")
Reported-by: syzbot+33e571025d88efd1312c@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=33e571025d88efd1312c
Tested-by: syzbot+33e571025d88efd1312c@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Reviewed-by: Chen Ridong <chenridong@huaweicloud.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-17 07:25:09 -10:00
Puranjay Mohan
2845989f2e bpf: Validate node_id in arena_alloc_pages()
arena_alloc_pages() accepts a plain int node_id and forwards it through
the entire allocation chain without any bounds checking.

Validate node_id before passing it down the allocation chain in
arena_alloc_pages().

Fixes: 317460317a ("bpf: Introduce bpf_arena.")
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260417152135.1383754-1-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-17 10:12:55 -07:00
Linus Torvalds
0b6bc3dbe6 tracing latency updates for 7.1:
- Add TIMERLAT_ALIGN osnoise option
 
   Add a timer alignment option for timerlat that makes it work like the
   cyclictest -A option. timelat creates threads to test the latency of the
   kernel. The alignment option will have these threads trigger at the
   alignment offsets from each other. Instead of having each thread wake up
   at the exact same time, if the alignment is set to "20" each thread will
   wake up at 20 microseconds from the previous one.
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Merge tag 'trace-latency-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing latency update from Steven Rostedt:

 - Add TIMERLAT_ALIGN osnoise option

   Add a timer alignment option for timerlat that makes it work like the
   cyclictest -A option. timelat creates threads to test the latency of
   the kernel. The alignment option will have these threads trigger at
   the alignment offsets from each other. Instead of having each thread
   wake up at the exact same time, if the alignment is set to "20" each
   thread will wake up at 20 microseconds from the previous one.

* tag 'trace-latency-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/osnoise: Add option to align tlat threads
2026-04-17 10:12:11 -07:00
Linus Torvalds
cb30bf881c tracing updates for v7.1:
- Fix printf format warning for bprintf
 
   sunrpc uses a trace_printk() that triggers a printf warning during the
   compile. Move the __printf() attribute around for when debugging is not
   enabled the warning will go away.
 
 - Remove redundant check for EVENT_FILE_FL_FREED in event_filter_write()
 
   The FREED flag is checked in the call to event_file_file() and then
   checked again right afterward, which is unneeded.
 
 - Clean up event_file_file() and event_file_data() helpers
 
   These helper functions played a different role in the past, but now with
   eventfs, the READ_ONCE() isn't needed. Simplify the code a bit and also
   add a warning to event_file_data() if the file or its data is not present.
 
 - Remove updating file->private_data in tracing open
 
   All access to the file private data is handled by the helper functions,
   which do not use file->private_data. Stop updating it on open.
 
 - Show ENUM names in function arguments via BTF in function tracing
 
   When showing the function arguments when func-args option is set for
   function tracing, if one of the arguments is found to be an enum, show the
   name of the enum instead of its number.
 
 - Add new trace_call__##name() API for tracepoints
 
   Tracepoints are enabled via static_branch() blocks, where when not
   enabled, there's only a nop that is in the code where the execution will
   just skip over it. When tracing is enabled, the nop is converted to a
   direct jump to the tracepoint code. Sometimes more calculations are
   required to be performed to update the parameters of the tracepoint. In
   this case, trace_##name##_enabled() is called which is a static_branch()
   that gets enabled only when the tracepoint is enabled. This allows the
   extra calculations to also be skipped by the nop:
 
   if (trace_foo_enabled()) {
       x = bar();
       trace_foo(x);
   }
 
   Where the x=bar() is only performed when foo is enabled. The problem with
   this approach is that there's now two static_branch() calls. One for
   checking if the tracepoint is enabled, and then again to know if the
   tracepoint should be called. The second one is redundant.
 
   Introduce trace_call__foo() that will call the foo() tracepoint directly
   without doing a static_branch():
 
   if (trace_foo_enabled()) {
       x = bar();
       trace_call__foo();
   }
 
 - Update various locations to use the new trace_call__##name() API
 
 - Move snapshot code out of trace.c
 
   Cleaning up trace.c to not be a "dump all", move the snapshot code out of
   it and into a new trace_snapshot.c file.
 
 - Clean up some "%*.s" to "%*s"
 
 - Allow boot kernel command line options to be called multiple times
 
   Have options like:
 
     ftrace_filter=foo ftrace_filter=bar ftrace_filter=zoo
 
   Equal to:
 
     ftrace_filter=foo,bar,zoo
 
 - Fix ipi_raise event CPU field to be a CPU field
 
   The ipi_raise target_cpus field is defined as a __bitmask(). There is now a
   __cpumask() field definition. Update the field to use that.
 
 - Have hist_field_name() use a snprintf() and not a series of strcat()
 
   It's safer to use snprintf() that a series of strcat().
 
 - Fix tracepoint regfunc balancing
 
   A tracepoint can define a "reg" and "unreg" function that gets called
   before the tracepoint is enabled, and after it is disabled respectively.
   But on error, after the "reg" func is called and the tracepoint is not
   enabled, the "unreg" function is not called to tear down what the "reg"
   function performed.
 
 - Fix output that shows what histograms are enabled
 
   Event variables are displayed incorrectly in the histogram output.
 
   Instead of "sched.sched_wakeup.$var", it is showing
   "$sched.sched_wakeup.var" where the '$' is in the incorrect location.
 
 - Some other simple cleanups.
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Merge tag 'trace-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - Fix printf format warning for bprintf

   sunrpc uses a trace_printk() that triggers a printf warning during
   the compile. Move the __printf() attribute around for when debugging
   is not enabled the warning will go away

 - Remove redundant check for EVENT_FILE_FL_FREED in
   event_filter_write()

   The FREED flag is checked in the call to event_file_file() and then
   checked again right afterward, which is unneeded

 - Clean up event_file_file() and event_file_data() helpers

   These helper functions played a different role in the past, but now
   with eventfs, the READ_ONCE() isn't needed. Simplify the code a bit
   and also add a warning to event_file_data() if the file or its data
   is not present

 - Remove updating file->private_data in tracing open

   All access to the file private data is handled by the helper
   functions, which do not use file->private_data. Stop updating it on
   open

 - Show ENUM names in function arguments via BTF in function tracing

   When showing the function arguments when func-args option is set for
   function tracing, if one of the arguments is found to be an enum,
   show the name of the enum instead of its number

 - Add new trace_call__##name() API for tracepoints

   Tracepoints are enabled via static_branch() blocks, where when not
   enabled, there's only a nop that is in the code where the execution
   will just skip over it. When tracing is enabled, the nop is converted
   to a direct jump to the tracepoint code. Sometimes more calculations
   are required to be performed to update the parameters of the
   tracepoint. In this case, trace_##name##_enabled() is called which is
   a static_branch() that gets enabled only when the tracepoint is
   enabled. This allows the extra calculations to also be skipped by the
   nop:

	if (trace_foo_enabled()) {
		x = bar();
		trace_foo(x);
	}

   Where the x=bar() is only performed when foo is enabled. The problem
   with this approach is that there's now two static_branch() calls. One
   for checking if the tracepoint is enabled, and then again to know if
   the tracepoint should be called. The second one is redundant

   Introduce trace_call__foo() that will call the foo() tracepoint
   directly without doing a static_branch():

	if (trace_foo_enabled()) {
		x = bar();
		trace_call__foo();
	}

 - Update various locations to use the new trace_call__##name() API

 - Move snapshot code out of trace.c

   Cleaning up trace.c to not be a "dump all", move the snapshot code
   out of it and into a new trace_snapshot.c file

 - Clean up some "%*.s" to "%*s"

 - Allow boot kernel command line options to be called multiple times

   Have options like:

	ftrace_filter=foo ftrace_filter=bar ftrace_filter=zoo

   Equal to:

	ftrace_filter=foo,bar,zoo

 - Fix ipi_raise event CPU field to be a CPU field

   The ipi_raise target_cpus field is defined as a __bitmask(). There is
   now a __cpumask() field definition. Update the field to use that

 - Have hist_field_name() use a snprintf() and not a series of strcat()

   It's safer to use snprintf() that a series of strcat()

 - Fix tracepoint regfunc balancing

   A tracepoint can define a "reg" and "unreg" function that gets called
   before the tracepoint is enabled, and after it is disabled
   respectively. But on error, after the "reg" func is called and the
   tracepoint is not enabled, the "unreg" function is not called to tear
   down what the "reg" function performed

 - Fix output that shows what histograms are enabled

   Event variables are displayed incorrectly in the histogram output

   Instead of "sched.sched_wakeup.$var", it is showing
   "$sched.sched_wakeup.var" where the '$' is in the incorrect location

 - Some other simple cleanups

* tag 'trace-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (24 commits)
  selftests/ftrace: Add test case for fully-qualified variable references
  tracing: Fix fully-qualified variable reference printing in histograms
  tracepoint: balance regfunc() on func_add() failure in tracepoint_add_func()
  tracing: Rebuild full_name on each hist_field_name() call
  tracing: Report ipi_raise target CPUs as cpumask
  tracing: Remove duplicate latency_fsnotify() stub
  tracing: Preserve repeated trace_trigger boot parameters
  tracing: Append repeated boot-time tracing parameters
  tracing: Remove spurious default precision from show_event_trigger/filter formats
  cpufreq: Use trace_call__##name() at guarded tracepoint call sites
  tracing: Remove tracing_alloc_snapshot() when snapshot isn't defined
  tracing: Move snapshot code out of trace.c and into trace_snapshot.c
  mm: damon: Use trace_call__##name() at guarded tracepoint call sites
  btrfs: Use trace_call__##name() at guarded tracepoint call sites
  spi: Use trace_call__##name() at guarded tracepoint call sites
  i2c: Use trace_call__##name() at guarded tracepoint call sites
  kernel: Use trace_call__##name() at guarded tracepoint call sites
  tracepoint: Add trace_call__##name() API
  tracing: trace_mmap.h: fix a kernel-doc warning
  tracing: Pretty-print enum parameters in function arguments
  ...
2026-04-17 09:43:12 -07:00
Linus Torvalds
c9e03d5948 Probes updates for v7.1
- fprobe: do not zero out unused fgraph_data. This removes unneeded
   memset of fgraph_data in fprobe entry handler.
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Merge tag 'probes-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull fprobe update from Masami Hiramatsu:

 - do not zero out unused fgraph_data. This removes unneeded memset of
   fgraph_data in fprobe entry handler.

* tag 'probes-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: fprobe: do not zero out unused fgraph_data
2026-04-17 09:18:32 -07:00
Linus Torvalds
01f492e181 Arm:
- Add support for tracing in the standalone EL2 hypervisor code, which
   should help both debugging and performance analysis.  This uses the
   new infrastructure for 'remote' trace buffers that can be exposed
   by non-kernel entities such as firmware, and which came through the
   tracing tree.
 
 - Add support for GICv5 Per Processor Interrupts (PPIs), as the starting
   point for supporting the new GIC architecture in KVM.
 
 - Finally add support for pKVM protected guests, where pages are unmapped
   from the host as they are faulted into the guest and can be shared back
   from the guest using pKVM hypercalls.  Protected guests are created
   using a new machine type identifier.  As the elusive guestmem has not
   yet delivered on its promises, anonymous memory is also supported.
 
   This is only a first step towards full isolation from the host; for
   example, the CPU register state and DMA accesses are not yet isolated.
   Because this does not really yet bring fully what it promises, it is
   hidden behind CONFIG_ARM_PKVM_GUEST + 'kvm-arm.mode=protected', and
   also triggers TAINT_USER when a VM is created.  Caveat emptor.
 
 - Rework the dreaded user_mem_abort() function to make it more
   maintainable, reducing the amount of state being exposed to the
   various helpers and rendering a substantial amount of state immutable.
 
 - Expand the Stage-2 page table dumper to support NV shadow page tables
   on a per-VM basis.
 
 - Tidy up the pKVM PSCI proxy code to be slightly less hard to follow.
 
 - Fix both SPE and TRBE in non-VHE configurations so that they do not
   generate spurious, out of context table walks that ultimately lead
   to very bad HW lockups.
 
 - A small set of patches fixing the Stage-2 MMU freeing in error cases.
 
 - Tighten-up accepted SMC immediate value to be only #0 for host
   SMCCC calls.
 
 - The usual cleanups and other selftest churn.
 
 LoongArch:
 
 - Use CSR_CRMD_PLV for kvm_arch_vcpu_in_kernel().
 
 - Add DMSINTC irqchip in kernel support.
 
 RISC-V:
 
 - Fix steal time shared memory alignment checks
 
 - Fix vector context allocation leak
 
 - Fix array out-of-bounds in pmu_ctr_read() and pmu_fw_ctr_read_hi()
 
 - Fix double-free of sdata in kvm_pmu_clear_snapshot_area()
 
 - Fix integer overflow in kvm_pmu_validate_counter_mask()
 
 - Fix shift-out-of-bounds in make_xfence_request()
 
 - Fix lost write protection on huge pages during dirty logging
 
 - Split huge pages during fault handling for dirty logging
 
 - Skip CSR restore if VCPU is reloaded on the same core
 
 - Implement kvm_arch_has_default_irqchip() for KVM selftests
 
 - Factored-out ISA checks into separate sources
 
 - Added hideleg to struct kvm_vcpu_config
 
 - Factored-out VCPU config into separate sources
 
 - Support configuration of per-VM HGATP mode from KVM user space
 
 s390:
 
 - Support for ESA (31-bit) guests inside nested hypervisors.
 
 - Remove restriction on memslot alignment, which is not needed anymore with
   the new gmap code.
 
 - Fix LPSW/E to update the bear (which of course is the breaking event
   address register).
 
 x86:
 
 - Shut up various UBSAN warnings on reading module parameter before they
   were initialized.
 
 - Don't zero-allocate page tables that are used for splitting hugepages in
   the TDP MMU, as KVM is guaranteed to set all SPTEs in the page table and
   thus write all bytes.
 
 - As an optimization, bail early when trying to unsync 4KiB mappings if the
   target gfn can just be mapped with a 2MiB hugepage.
 
 x86 generic:
 
 - Copy single-chunk MMIO write values into struct kvm_vcpu (more precisely
   struct kvm_mmio_fragment) to fix use-after-free stack bugs where KVM
   would dereference stack pointer after an exit to userspace.
 
 - Clean up and comment the emulated MMIO code to try to make it easier to
   maintain (not necessarily "easy", but "easier").
 
 - Move VMXON+VMXOFF and EFER.SVME toggling out of KVM (not *all* of VMX
   and SVM enabling) as it is needed for trusted I/O.
 
 - Advertise support for AVX512 Bit Matrix Multiply (BMM) instructions
 
 - Immediately fail the build if a required #define is missing in one of
   KVM's headers that is included multiple times.
 
 - Reject SET_GUEST_DEBUG with -EBUSY if there's an already injected
   exception, mostly to prevent syzkaller from abusing the uAPI to
   trigger WARNs, but also because it can help prevent userspace from
   unintentionally crashing the VM.
 
 - Exempt SMM from CPUID faulting on Intel, as per the spec.
 
 - Misc hardening and cleanup changes.
 
 x86 (AMD):
 
 - Fix and optimize IRQ window inhibit handling for AVIC; make it per-vCPU
   so that KVM doesn't prematurely re-enable AVIC if multiple
   vCPUs have to-be-injected IRQs.
 
 - Clean up and optimize the OSVW handling, avoiding a bug in which KVM would
   overwrite state when enabling virtualization on multiple CPUs in parallel.
   This should not be a problem because OSVW should usually be the same for
   all CPUs.
 
 - Drop a WARN in KVM_MEMORY_ENCRYPT_REG_REGION where KVM complains about a
   "too large" size based purely on user input.
 
 - Clean up and harden the pinning code for KVM_MEMORY_ENCRYPT_REG_REGION.
 
 - Disallow synchronizing a VMSA of an already-launched/encrypted vCPU, as
   doing so for an SNP guest will crash the host due to an RMP violation
   page fault.
 
 - Overhaul KVM's APIs for detecting SEV+ guests so that VM-scoped queries
   are required to hold kvm->lock, and enforce it by lockdep.  Fix various
   bugs where sev_guest() was not ensured to be stable for the whole
   duration of a function or ioctl.
 
 - Convert a pile of kvm->lock SEV code to guard().
 
 - Play nicer with userspace that does not enable KVM_CAP_EXCEPTION_PAYLOAD,
   for which KVM needs to set CR2 and DR6 as a response to ioctls such as
   KVM_GET_VCPU_EVENTS (even if the payload would end up in EXITINFO2
   rather than CR2, for example).  Only set CR2 and DR6 when consumption of
   the payload is imminent, but on the other hand force delivery of the
   payload in all paths where userspace retrieves CR2 or DR6.
 
 - Use vcpu->arch.cr2 when updating vmcb12's CR2 on nested #VMEXIT instead
   of vmcb02->save.cr2.  The value is out of sync after a save/restore
   or after a #PF is injected into L2.
 
 - Fix a class of nSVM bugs where some fields written by the CPU are not
   synchronized from vmcb02 to cached vmcb12 after VMRUN, and so are not
   up-to-date when saved by KVM_GET_NESTED_STATE.
 
 - Fix a class of bugs where the ordering between KVM_SET_NESTED_STATE and
   KVM_SET_{S}REGS could cause vmcb02 to be incorrectly initialized after
   save+restore.
 
 - Add a variety of missing nSVM consistency checks.
 
 - Fix several bugs where KVM failed to correctly update VMCB fields on
   nested #VMEXIT.
 
 - Fix several bugs where KVM failed to correctly synthesize #UD or #GP for
   SVM-related instructions.
 
 - Add support for save+restore of virtualized LBRs (on SVM).
 
 - Refactor various helpers and macros to improve clarity and (hopefully)
   make the code easier to maintain.
 
 - Aggressively sanitize fields when copying from vmcb12, to guard against
   unintentionally allowing L1 to utilize yet-to-be-defined features.
 
 - Fix several bugs where KVM botched rAX legality checks when emulating SVM
   instructions.  There are remaining issues in that KVM doesn't handle size
   prefix overrides for 64-bit guests.
 
 - Fail emulation of VMRUN/VMLOAD/VMSAVE if mapping vmcb12 fails instead of
   somewhat arbitrarily synthesizing #GP (i.e. don't double down on AMD's
   architectural but sketchy behavior of generating #GP for "unsupported"
   addresses).
 
 - Cache all used vmcb12 fields to further harden against TOCTOU bugs.
 
 x86 (Intel):
 
 - Drop obsolete branch hint prefixes from the VMX instruction macros.
 
 - Use ASM_INPUT_RM() in __vmcs_writel() to coerce clang into using a
   register input when appropriate.
 
 - Code cleanups.
 
 guest_memfd:
 
 - Don't mark guest_memfd folios as accessed, as guest_memfd doesn't support
   reclaim, the memory is unevictable, and there is no storage to write
   back to.
 
 LoongArch selftests:
 
 - Add KVM PMU test cases
 
 s390 selftests:
 
 - Enable more memory selftests.
 
 x86 selftests:
 
 - Add support for Hygon CPUs in KVM selftests.
 
 - Fix a bug in the MSR test where it would get false failures on AMD/Hygon
   CPUs with exactly one of RDPID or RDTSCP.
 
 - Add an MADV_COLLAPSE testcase for guest_memfd as a regression test for a
   bug where the kernel would attempt to collapse guest_memfd folios against
   KVM's will.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "Arm:

   - Add support for tracing in the standalone EL2 hypervisor code,
     which should help both debugging and performance analysis. This
     uses the new infrastructure for 'remote' trace buffers that can be
     exposed by non-kernel entities such as firmware, and which came
     through the tracing tree

   - Add support for GICv5 Per Processor Interrupts (PPIs), as the
     starting point for supporting the new GIC architecture in KVM

   - Finally add support for pKVM protected guests, where pages are
     unmapped from the host as they are faulted into the guest and can
     be shared back from the guest using pKVM hypercalls. Protected
     guests are created using a new machine type identifier. As the
     elusive guestmem has not yet delivered on its promises, anonymous
     memory is also supported

     This is only a first step towards full isolation from the host; for
     example, the CPU register state and DMA accesses are not yet
     isolated. Because this does not really yet bring fully what it
     promises, it is hidden behind CONFIG_ARM_PKVM_GUEST +
     'kvm-arm.mode=protected', and also triggers TAINT_USER when a VM is
     created. Caveat emptor

   - Rework the dreaded user_mem_abort() function to make it more
     maintainable, reducing the amount of state being exposed to the
     various helpers and rendering a substantial amount of state
     immutable

   - Expand the Stage-2 page table dumper to support NV shadow page
     tables on a per-VM basis

   - Tidy up the pKVM PSCI proxy code to be slightly less hard to
     follow

   - Fix both SPE and TRBE in non-VHE configurations so that they do not
     generate spurious, out of context table walks that ultimately lead
     to very bad HW lockups

   - A small set of patches fixing the Stage-2 MMU freeing in error
     cases

   - Tighten-up accepted SMC immediate value to be only #0 for host
     SMCCC calls

   - The usual cleanups and other selftest churn

  LoongArch:

   - Use CSR_CRMD_PLV for kvm_arch_vcpu_in_kernel()

   - Add DMSINTC irqchip in kernel support

  RISC-V:

   - Fix steal time shared memory alignment checks

   - Fix vector context allocation leak

   - Fix array out-of-bounds in pmu_ctr_read() and pmu_fw_ctr_read_hi()

   - Fix double-free of sdata in kvm_pmu_clear_snapshot_area()

   - Fix integer overflow in kvm_pmu_validate_counter_mask()

   - Fix shift-out-of-bounds in make_xfence_request()

   - Fix lost write protection on huge pages during dirty logging

   - Split huge pages during fault handling for dirty logging

   - Skip CSR restore if VCPU is reloaded on the same core

   - Implement kvm_arch_has_default_irqchip() for KVM selftests

   - Factored-out ISA checks into separate sources

   - Added hideleg to struct kvm_vcpu_config

   - Factored-out VCPU config into separate sources

   - Support configuration of per-VM HGATP mode from KVM user space

  s390:

   - Support for ESA (31-bit) guests inside nested hypervisors

   - Remove restriction on memslot alignment, which is not needed
     anymore with the new gmap code

   - Fix LPSW/E to update the bear (which of course is the breaking
     event address register)

  x86:

   - Shut up various UBSAN warnings on reading module parameter before
     they were initialized

   - Don't zero-allocate page tables that are used for splitting
     hugepages in the TDP MMU, as KVM is guaranteed to set all SPTEs in
     the page table and thus write all bytes

   - As an optimization, bail early when trying to unsync 4KiB mappings
     if the target gfn can just be mapped with a 2MiB hugepage

  x86 generic:

   - Copy single-chunk MMIO write values into struct kvm_vcpu (more
     precisely struct kvm_mmio_fragment) to fix use-after-free stack
     bugs where KVM would dereference stack pointer after an exit to
     userspace

   - Clean up and comment the emulated MMIO code to try to make it
     easier to maintain (not necessarily "easy", but "easier")

   - Move VMXON+VMXOFF and EFER.SVME toggling out of KVM (not *all* of
     VMX and SVM enabling) as it is needed for trusted I/O

   - Advertise support for AVX512 Bit Matrix Multiply (BMM) instructions

   - Immediately fail the build if a required #define is missing in one
     of KVM's headers that is included multiple times

   - Reject SET_GUEST_DEBUG with -EBUSY if there's an already injected
     exception, mostly to prevent syzkaller from abusing the uAPI to
     trigger WARNs, but also because it can help prevent userspace from
     unintentionally crashing the VM

   - Exempt SMM from CPUID faulting on Intel, as per the spec

   - Misc hardening and cleanup changes

  x86 (AMD):

   - Fix and optimize IRQ window inhibit handling for AVIC; make it
     per-vCPU so that KVM doesn't prematurely re-enable AVIC if multiple
     vCPUs have to-be-injected IRQs

   - Clean up and optimize the OSVW handling, avoiding a bug in which
     KVM would overwrite state when enabling virtualization on multiple
     CPUs in parallel. This should not be a problem because OSVW should
     usually be the same for all CPUs

   - Drop a WARN in KVM_MEMORY_ENCRYPT_REG_REGION where KVM complains
     about a "too large" size based purely on user input

   - Clean up and harden the pinning code for KVM_MEMORY_ENCRYPT_REG_REGION

   - Disallow synchronizing a VMSA of an already-launched/encrypted
     vCPU, as doing so for an SNP guest will crash the host due to an
     RMP violation page fault

   - Overhaul KVM's APIs for detecting SEV+ guests so that VM-scoped
     queries are required to hold kvm->lock, and enforce it by lockdep.
     Fix various bugs where sev_guest() was not ensured to be stable for
     the whole duration of a function or ioctl

   - Convert a pile of kvm->lock SEV code to guard()

   - Play nicer with userspace that does not enable
     KVM_CAP_EXCEPTION_PAYLOAD, for which KVM needs to set CR2 and DR6
     as a response to ioctls such as KVM_GET_VCPU_EVENTS (even if the
     payload would end up in EXITINFO2 rather than CR2, for example).
     Only set CR2 and DR6 when consumption of the payload is imminent,
     but on the other hand force delivery of the payload in all paths
     where userspace retrieves CR2 or DR6

   - Use vcpu->arch.cr2 when updating vmcb12's CR2 on nested #VMEXIT
     instead of vmcb02->save.cr2. The value is out of sync after a
     save/restore or after a #PF is injected into L2

   - Fix a class of nSVM bugs where some fields written by the CPU are
     not synchronized from vmcb02 to cached vmcb12 after VMRUN, and so
     are not up-to-date when saved by KVM_GET_NESTED_STATE

   - Fix a class of bugs where the ordering between KVM_SET_NESTED_STATE
     and KVM_SET_{S}REGS could cause vmcb02 to be incorrectly
     initialized after save+restore

   - Add a variety of missing nSVM consistency checks

   - Fix several bugs where KVM failed to correctly update VMCB fields
     on nested #VMEXIT

   - Fix several bugs where KVM failed to correctly synthesize #UD or
     #GP for SVM-related instructions

   - Add support for save+restore of virtualized LBRs (on SVM)

   - Refactor various helpers and macros to improve clarity and
     (hopefully) make the code easier to maintain

   - Aggressively sanitize fields when copying from vmcb12, to guard
     against unintentionally allowing L1 to utilize yet-to-be-defined
     features

   - Fix several bugs where KVM botched rAX legality checks when
     emulating SVM instructions. There are remaining issues in that KVM
     doesn't handle size prefix overrides for 64-bit guests

   - Fail emulation of VMRUN/VMLOAD/VMSAVE if mapping vmcb12 fails
     instead of somewhat arbitrarily synthesizing #GP (i.e. don't double
     down on AMD's architectural but sketchy behavior of generating #GP
     for "unsupported" addresses)

   - Cache all used vmcb12 fields to further harden against TOCTOU bugs

  x86 (Intel):

   - Drop obsolete branch hint prefixes from the VMX instruction macros

   - Use ASM_INPUT_RM() in __vmcs_writel() to coerce clang into using a
     register input when appropriate

   - Code cleanups

  guest_memfd:

   - Don't mark guest_memfd folios as accessed, as guest_memfd doesn't
     support reclaim, the memory is unevictable, and there is no storage
     to write back to

  LoongArch selftests:

   - Add KVM PMU test cases

  s390 selftests:

   - Enable more memory selftests

  x86 selftests:

   - Add support for Hygon CPUs in KVM selftests

   - Fix a bug in the MSR test where it would get false failures on
     AMD/Hygon CPUs with exactly one of RDPID or RDTSCP

   - Add an MADV_COLLAPSE testcase for guest_memfd as a regression test
     for a bug where the kernel would attempt to collapse guest_memfd
     folios against KVM's will"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (373 commits)
  KVM: x86: use inlines instead of macros for is_sev_*guest
  x86/virt: Treat SVM as unsupported when running as an SEV+ guest
  KVM: SEV: Goto an existing error label if charging misc_cg for an ASID fails
  KVM: SVM: Move lock-protected allocation of SEV ASID into a separate helper
  KVM: SEV: use mutex guard in snp_handle_guest_req()
  KVM: SEV: use mutex guard in sev_mem_enc_unregister_region()
  KVM: SEV: use mutex guard in sev_mem_enc_ioctl()
  KVM: SEV: use mutex guard in snp_launch_update()
  KVM: SEV: Assert that kvm->lock is held when querying SEV+ support
  KVM: SEV: Document that checking for SEV+ guests when reclaiming memory is "safe"
  KVM: SEV: Hide "struct kvm_sev_info" behind CONFIG_KVM_AMD_SEV=y
  KVM: SEV: WARN on unhandled VM type when initializing VM
  KVM: LoongArch: selftests: Add PMU overflow interrupt test
  KVM: LoongArch: selftests: Add basic PMU event counting test
  KVM: LoongArch: selftests: Add cpucfg read/write helpers
  LoongArch: KVM: Add DMSINTC inject msi to vCPU
  LoongArch: KVM: Add DMSINTC device support
  LoongArch: KVM: Make vcpu_is_preempted() as a macro rather than function
  LoongArch: KVM: Move host CSR_GSTAT save and restore in context switch
  LoongArch: KVM: Move host CSR_EENTRY save and restore in context switch
  ...
2026-04-17 07:18:03 -07:00
Linus Torvalds
440d6635b2 mm.git review status for linus..mm-nonmm-stable
Total patches:       126
 Reviews/patch:       0.92
 Reviewed rate:       76%
 
 - The 2 patch series "pid: make sub-init creation retryable" from Oleg
   Nesterov increases the robustness of our creation of init in a new
   namespace.  By clearing away some historical cruft which is no longer
   needed.  Also some documentation fixups are provided.
 
 - The 2 patch series "selftests/fchmodat2: Error handling and general"
   from Mark Brown has a fixup and a cleanup for the fchmodat2() syscall
   selftest.
 
 - The 3 patch series "lib: polynomial: Move to math/ and clean up" from
   Andy Shevchenko does as advertised.
 
 - The 3 patch series "hung_task: Provide runtime reset interface for
   hung task detector" from Aaron Tomlin gives administrators the ability
   to zero out /proc/sys/kernel/hung_task_detect_count.
 
 - The 2 patch series "tools/getdelays: use the static UAPI headers from
   tools/include/uapi" from Thomas Weißschuh teaches getdelays to use the
   in-kernel UAPI headers rather than the system-provided ones.
 
 - The 5 patch series "watchdog/hardlockup: Improvements to hardlockup"
   from Mayank Rungta provides several cleanups and fixups to the
   hardlockup detector code and its documentation.
 
 - The 2 patch series "lib/bch: fix undefined behavior from signed
   left-shifts" from Josh Law provides a couple of small/theoretical fixes
   in the bch code.
 
 - The 2 patch series "ocfs2/dlm: fix two bugs in dlm_match_regions()"
   from Junrui Luo does what is claims.
 
 - The 27 patch series "cleanup the RAID5 XOR library" from Christoph
   Hellwig is a quite far-reaching cleanup to this code.  I can't do better
   than to quote Christoph:
 
     The XOR library used for the RAID5 parity is a bit of a mess right
     now.  The main file sits in crypto/ despite not being cryptography and
     not using the crypto API, with the generic implementations sitting in
     include/asm-generic and the arch implementations sitting in an asm/
     header in theory.  The latter doesn't work for many cases, so
     architectures often build the code directly into the core kernel, or
     create another module for the architecture code.
 
     Change this to a single module in lib/ that also contains the
     architecture optimizations, similar to the library work Eric Biggers
     has done for the CRC and crypto libraries later.  After that it
     changes to better calling conventions that allow for smarter
     architecture implementations (although none is contained here yet),
     and uses static_call to avoid indirection function call overhead.
 
 - The 2 patch series "lib/list_sort: Clean up list_sort() scheduling
   workarounds" from Kuan-Wei Chiu cleans up this library code by removing
   a hacky thing which was added for UBIFS, which UBIFS doesn't actually
   need.
 
 - The 5 patch series "Fix bugs in extract_iter_to_sg()" from Christian
   Ehrhardt fixes a few bugs in the scatterlist code, adds in-kernel tests
   for the now-fixed bugs and fixes a leak in the test itself.
 
 - The 3 patch series "kdump: Enable LUKS-encrypted dump target support
   in ARM64 and PowerPC" from Coiby Xu eenables support of the
   LUKS-encrypted device dump target on arm64 and powerpc.
 
 - The 4 patch series "ocfs2: consolidate extent list validation into
   block read callbacks" from Joseph Qi addresses ocfs2's validation of
   extent list fields - cleanup, simplification, robustness.  (Kernel test
   robot loves mounting corrupted fs images!)
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Merge tag 'mm-nonmm-stable-2026-04-15-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "pid: make sub-init creation retryable" (Oleg Nesterov)

   Make creation of init in a new namespace more robust by clearing away
   some historical cruft which is no longer needed. Also some
   documentation fixups

 - "selftests/fchmodat2: Error handling and general" (Mark Brown)

   Fix and a cleanup for the fchmodat2() syscall selftest

 - "lib: polynomial: Move to math/ and clean up" (Andy Shevchenko)

 - "hung_task: Provide runtime reset interface for hung task detector"
   (Aaron Tomlin)

   Give administrators the ability to zero out
   /proc/sys/kernel/hung_task_detect_count

 - "tools/getdelays: use the static UAPI headers from
   tools/include/uapi" (Thomas Weißschuh)

   Teach getdelays to use the in-kernel UAPI headers rather than the
   system-provided ones

 - "watchdog/hardlockup: Improvements to hardlockup" (Mayank Rungta)

   Several cleanups and fixups to the hardlockup detector code and its
   documentation

 - "lib/bch: fix undefined behavior from signed left-shifts" (Josh Law)

   A couple of small/theoretical fixes in the bch code

 - "ocfs2/dlm: fix two bugs in dlm_match_regions()" (Junrui Luo)

 - "cleanup the RAID5 XOR library" (Christoph Hellwig)

   A quite far-reaching cleanup to this code. I can't do better than to
   quote Christoph:

     "The XOR library used for the RAID5 parity is a bit of a mess right
      now. The main file sits in crypto/ despite not being cryptography
      and not using the crypto API, with the generic implementations
      sitting in include/asm-generic and the arch implementations
      sitting in an asm/ header in theory. The latter doesn't work for
      many cases, so architectures often build the code directly into
      the core kernel, or create another module for the architecture
      code.

      Change this to a single module in lib/ that also contains the
      architecture optimizations, similar to the library work Eric
      Biggers has done for the CRC and crypto libraries later. After
      that it changes to better calling conventions that allow for
      smarter architecture implementations (although none is contained
      here yet), and uses static_call to avoid indirection function call
      overhead"

 - "lib/list_sort: Clean up list_sort() scheduling workarounds"
   (Kuan-Wei Chiu)

   Clean up this library code by removing a hacky thing which was added
   for UBIFS, which UBIFS doesn't actually need

 - "Fix bugs in extract_iter_to_sg()" (Christian Ehrhardt)

   Fix a few bugs in the scatterlist code, add in-kernel tests for the
   now-fixed bugs and fix a leak in the test itself

 - "kdump: Enable LUKS-encrypted dump target support in ARM64 and
   PowerPC" (Coiby Xu)

   Enable support of the LUKS-encrypted device dump target on arm64 and
   powerpc

 - "ocfs2: consolidate extent list validation into block read callbacks"
   (Joseph Qi)

   Cleanup, simplify, and make more robust ocfs2's validation of extent
   list fields (Kernel test robot loves mounting corrupted fs images!)

* tag 'mm-nonmm-stable-2026-04-15-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (127 commits)
  ocfs2: validate group add input before caching
  ocfs2: validate bg_bits during freefrag scan
  ocfs2: fix listxattr handling when the buffer is full
  doc: watchdog: fix typos etc
  update Sean's email address
  ocfs2: use get_random_u32() where appropriate
  ocfs2: split transactions in dio completion to avoid credit exhaustion
  ocfs2: remove redundant l_next_free_rec check in __ocfs2_find_path()
  ocfs2: validate extent block list fields during block read
  ocfs2: remove empty extent list check in ocfs2_dx_dir_lookup_rec()
  ocfs2: validate dx_root extent list fields during block read
  ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY
  ocfs2: handle invalid dinode in ocfs2_group_extend
  .get_maintainer.ignore: add Askar
  ocfs2: validate bg_list extent bounds in discontig groups
  checkpatch: exclude forward declarations of const structs
  tools/accounting: handle truncated taskstats netlink messages
  taskstats: set version in TGID exit notifications
  ocfs2/heartbeat: fix slot mapping rollback leaks on error paths
  arm64,ppc64le/kdump: pass dm-crypt keys to kdump kernel
  ...
2026-04-16 20:11:56 -07:00
Yihan Ding
b960430ea8 bpf: allow UTF-8 literals in bpf_bprintf_prepare()
bpf_bprintf_prepare() only needs ASCII parsing for conversion
specifiers. Plain text can safely carry bytes >= 0x80, so allow
UTF-8 literals outside '%' sequences while keeping ASCII control
bytes rejected and format specifiers ASCII-only.

This keeps existing parsing rules for format directives unchanged,
while allowing helpers such as bpf_trace_printk() to emit UTF-8
literal text.

Update test_snprintf_negative() in the same commit so selftests keep
matching the new plain-text vs format-specifier split during bisection.

Fixes: 48cac3f4a9 ("bpf: Implement formatted output helpers with bstr_printf")
Signed-off-by: Yihan Ding <dingyihan@uniontech.com>
Acked-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/20260416120142.1420646-2-dingyihan@uniontech.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-16 15:53:32 -07:00
Mykyta Yatsenko
4d0a375887 bpf: Fix NULL deref in map_kptr_match_type for scalar regs
Commit ab6c637ad0 ("bpf: Fix a bpf_kptr_xchg() issue with local
kptr") refactored map_kptr_match_type() to branch on btf_is_kernel()
before checking base_type(). A scalar register stored into a kptr
slot has no btf, so the btf_is_kernel(reg->btf) call dereferences
NULL.

Move the base_type() != PTR_TO_BTF_ID guard before any reg->btf
access.

Fixes: ab6c637ad0 ("bpf: Fix a bpf_kptr_xchg() issue with local kptr")
Reported-by: Hiker Cl <clhiker365@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221372
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Acked-by: Paul Chaignon <paul.chaignon@gmail.com>
Link: https://lore.kernel.org/r/20260416-kptr_crash-v1-1-5589356584b4@meta.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-16 15:20:26 -07:00
Thomas Gleixner
4096fd0e8e clockevents: Add missing resets of the next_event_forced flag
The prevention mechanism against timer interrupt starvation missed to reset
the next_event_forced flag in a couple of places:

    - When the clock event state changes. That can cause the flag to be
      stale over a shutdown/startup sequence

    - When a non-forced event is armed, which then prevents rearming before
      that event. If that event is far out in the future this will cause
      missed timer interrupts.

    - In the suspend wakeup handler.

That led to stalls which have been reported by several people.

Add the missing resets, which fixes the problems for the reporters.

Fixes: d6e152d905 ("clockevents: Prevent timer interrupt starvation")
Reported-by: Hanabishi <i.r.e.c.c.a.k.u.n+kernel.org@gmail.com>
Reported-by: Eric Naim <dnaim@cachyos.org>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Hanabishi <i.r.e.c.c.a.k.u.n+kernel.org@gmail.com>
Tested-by: Eric Naim <dnaim@cachyos.org>
Cc: stable@vger.kernel.org
Closes: https://lore.kernel.org/68d1e9ac-2780-4be3-8ee3-0788062dd3a4@gmail.com
Link: https://patch.msgid.link/87340xfeje.ffs@tglx
2026-04-16 21:22:04 +02:00
Tomas Glozar
4245bf4dc5 tracing/osnoise: Add option to align tlat threads
Add an option called TIMERLAT_ALIGN to osnoise/options, together with a
corresponding setting osnoise/timerlat_align_us.

This option sets the alignment of wakeup times between different
timerlat threads, similarly to cyclictest's -A/--aligned option. If
TIMERLAT_ALIGN is set, the first thread that reaches the first cycle
records its first wake-up time. Each following thread sets its first
wake-up time to a fixed offset from the recorded time, and increments
it by the same offset.

Example:

osnoise/timerlat_period is set to 1000, osnoise/timerlat_align_us is
set to 20. There are four threads, on CPUs 1 to 4.

- CPU 4 enters first cycle first. The current time is 20000us, so
the wake-up of the first cycle is set to 21000us. This time is recorded.
- CPU 2 enter first cycle next. It reads the recorded time, increments
it to 21020us, and uses this value as its own wake-up time for the first
cycle.
- CPU 3 enters first cycle next. It reads the recorded time, increments
it to 21040 us, and uses the value as its own wake-up time.
- CPU 1 proceeds analogically.

In each next cycle, the wake-up time (called "absolute period" in
timerlat code) is incremented by the (relative) period of 1000us. Thus,
the wake-ups in the following cycles (provided the times are reached and
not in the past) will be as follows:

CPU 1		CPU 2		CPU 3	 	CPU 4
21080us		21020us		21040us		21000us
22080us		22020us		22040us		22000us
...		...		...		...

Even if any cycle is skipped due to e.g. the first cycle calculation
happening later, the alignment stays in place.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Luis Goncalves <lgoncalv@redhat.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Link: https://patch.msgid.link/20260416115942.544032-1-tglozar@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>
Reviewed-by: Wander Lairson Costa <wander@redhat.com>
Reviewed-by: Crystal Wood <crwood@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-04-16 10:42:30 -04:00
Xu Kuohai
07ae6c130b bpf: Add helper to detect indirect jump targets
Introduce helper bpf_insn_is_indirect_target to check whether a BPF
instruction is an indirect jump target.

Since the verifier knows which instructions are indirect jump targets,
add a new flag indirect_target to struct bpf_insn_aux_data to mark
them. The verifier sets this flag when verifying an indirect jump target
instruction, and the helper checks the flag to determine whether an
instruction is an indirect jump target.

Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com> #v8
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> #v12
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20260416064341.151802-4-xukuohai@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-16 07:03:40 -07:00
Xu Kuohai
d9ef13f727 bpf: Pass bpf_verifier_env to JIT
Pass bpf_verifier_env to bpf_int_jit_compile(). The follow-up patch will
use env->insn_aux_data in the JIT stage to detect indirect jump targets.

Since bpf_prog_select_runtime() can be called by cbpf and lib/test_bpf.c
code without verifier, introduce helper __bpf_prog_select_runtime()
to accept the env parameter.

Remove the call to bpf_prog_select_runtime() in bpf_prog_load(), and
switch to call __bpf_prog_select_runtime() in the verifier, with env
variable passed. The original bpf_prog_select_runtime() is preserved for
cbpf and lib/test_bpf.c, where env is NULL.

Now all constants blinding calls are moved into the verifier, except
the cbpf and lib/test_bpf.c cases. The instructions arrays are adjusted
by bpf_patch_insn_data() function for normal cases, so there is no need
to call adjust_insn_arrays() in bpf_jit_blind_constants(). Remove it.

Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com> # v8
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> # v12
Acked-by: Hengqi Chen <hengqi.chen@gmail.com> # v14
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20260416064341.151802-3-xukuohai@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-16 07:03:40 -07:00
Xu Kuohai
d3e945223e bpf: Move constants blinding out of arch-specific JITs
During the JIT stage, constants blinding rewrites instructions but only
rewrites the private instruction copy of the JITed subprog, leaving the
global env->prog->insnsi and env->insn_aux_data untouched. This causes a
mismatch between subprog instructions and the global state, making it
difficult to use the global data in the JIT.

To avoid this mismatch, and given that all arch-specific JITs already
support constants blinding, move it to the generic verifier code, and
switch to rewrite the global env->prog->insnsi with the global states
adjusted, as other rewrites in the verifier do.

This removes the constants blinding calls in each JIT, which are largely
duplicated code across architectures.

Since constants blinding is only required for JIT, and there are two
JIT entry functions, jit_subprogs() for BPF programs with multiple
subprogs and bpf_prog_select_runtime() for programs with no subprogs,
move the constants blinding invocation into these two functions.

In the verifier path, bpf_patch_insn_data() is used to keep global
verifier auxiliary data in sync with patched instructions. A key
question is whether this global auxiliary data should be restored
on the failure path.

Besides instructions, bpf_patch_insn_data() adjusts:
  - prog->aux->poke_tab
  - env->insn_array_maps
  - env->subprog_info
  - env->insn_aux_data

For prog->aux->poke_tab, it is only used by JIT or only meaningful after
JIT succeeds, so it does not need to be restored on the failure path.

For env->insn_array_maps, when JIT fails, programs using insn arrays
are rejected by bpf_insn_array_ready() due to missing JIT addresses.
Hence, env->insn_array_maps is only meaningful for JIT and does not need
to be restored.

For subprog_info, if jit_subprogs fails and CONFIG_BPF_JIT_ALWAYS_ON
is not enabled, kernel falls back to interpreter. In this case,
env->subprog_info is used to determine subprogram stack depth. So it
must be restored on failure.

For env->insn_aux_data, it is freed by clear_insn_aux_data() at the
end of bpf_check(). Before freeing, clear_insn_aux_data() loops over
env->insn_aux_data to release jump targets recorded in it. The loop
uses env->prog->len as the array length, but this length no longer
matches the actual size of the adjusted env->insn_aux_data array after
constants blinding.

To address it, a simple approach is to keep insn_aux_data as adjusted
after failure, since it will be freed shortly, and record its actual size
for the loop in clear_insn_aux_data(). But since clear_insn_aux_data()
uses the same index to loop over both env->prog->insnsi and env->insn_aux_data,
this approach results in incorrect index for the insnsi array. So an
alternative approach is adopted: clone the original env->insn_aux_data
before blinding and restore it after failure, similar to env->prog.

For classic BPF programs, constants blinding works as before since it
is still invoked from bpf_prog_select_runtime().

Reviewed-by: Anton Protopopov <a.s.protopopov@gmail.com> # v8
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com> # powerpc jit
Reviewed-by: Pu Lehui <pulehui@huawei.com> # riscv jit
Acked-by: Hengqi Chen <hengqi.chen@gmail.com> # loongarch jit
Signed-off-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20260416064341.151802-2-xukuohai@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-16 07:03:40 -07:00
Linus Torvalds
fdbfee9fc5 Runtime Verification updates for 7.1:
- Refactor da_monitor header to share handlers across monitor types
 
   No functional changes, only less code duplication.
 
 - Add Hybrid Automata model class
 
   Add a new model class that extends deterministic automata by adding
   constraints on transitions and states. Those constraints can take into
   account wall-clock time and as such allow RV monitor to make
   assertions on real time. Add documentation and code generation
   scripts.
 
 - Add stall monitor as hybrid automaton example
 
   Add a monitor that triggers a violation when a task is stalling as an
   example of automaton working with real time variables.
 
 - Convert the opid monitor to a hybrid automaton
 
   The opid monitor can be heavily simplified if written as a hybrid
   automaton: instead of tracking preempt and interrupt enable/disable
   events, it can just run constraints on the preemption/interrupt
   states when events like wakeup and need_resched verify.
 
 - Add support for per-object monitors in DA/HA
 
   Allow writing deterministic and hybrid automata monitors for generic
   objects (e.g. any struct), by exploiting a hash table where objects
   are saved. This allows to track more than just tasks in RV. For
   instance it will be used to track deadline entities in deadline
   monitors.
 
 - Add deadline tracepoints and move some deadline utilities
 
   Prepare the ground for deadline monitors by defining events and
   exporting helpers.
 
 - Add nomiss deadline monitor
 
   Add first example of deadline monitor asserting all entities complete
   before their deadline.
 
 - Improve rvgen error handling
 
   Introduce AutomataError exception class and better handle expected
   exceptions while showing a backtrace for unexpected ones.
 
 - Improve python code quality in rvgen
 
   Refactor the rvgen generation scripts to align with python best
   practices: use f-strings instead of %, use len() instead of __len__(),
   remove semicolons, use context managers for file operations, fix
   whitespace violations, extract magic strings into constants, remove
   unused imports and methods.
 
 - Fix small bugs in rvgen
 
   The generator scripts presented some corner case bugs: logical error in
   validating what a correct dot file looks like, fix an isinstance()
   check, enforce a dot file has an initial state, fix type annotations
   and typos in comments.
 
 - rvgen refactoring
 
   Refactor automata.py to use iterator-based parsing and handle required
   arguments directly in argparse.
 
 - Allow epoll in rtapp-sleep monitor
 
   The epoll_wait call is now rt-friendly so it should be allowed in the
   sleep monitor as a valid sleep method.
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Merge tag 'trace-rv-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull runtime verification updates from Steven Rostedt:

 - Refactor da_monitor header to share handlers across monitor types

   No functional changes, only less code duplication.

 - Add Hybrid Automata model class

   Add a new model class that extends deterministic automata by adding
   constraints on transitions and states. Those constraints can take
   into account wall-clock time and as such allow RV monitor to make
   assertions on real time. Add documentation and code generation
   scripts.

 - Add stall monitor as hybrid automaton example

   Add a monitor that triggers a violation when a task is stalling as an
   example of automaton working with real time variables.

 - Convert the opid monitor to a hybrid automaton

   The opid monitor can be heavily simplified if written as a hybrid
   automaton: instead of tracking preempt and interrupt enable/disable
   events, it can just run constraints on the preemption/interrupt
   states when events like wakeup and need_resched verify.

 - Add support for per-object monitors in DA/HA

   Allow writing deterministic and hybrid automata monitors for generic
   objects (e.g. any struct), by exploiting a hash table where objects
   are saved. This allows to track more than just tasks in RV. For
   instance it will be used to track deadline entities in deadline
   monitors.

 - Add deadline tracepoints and move some deadline utilities

   Prepare the ground for deadline monitors by defining events and
   exporting helpers.

 - Add nomiss deadline monitor

   Add first example of deadline monitor asserting all entities complete
   before their deadline.

 - Improve rvgen error handling

   Introduce AutomataError exception class and better handle expected
   exceptions while showing a backtrace for unexpected ones.

 - Improve python code quality in rvgen

   Refactor the rvgen generation scripts to align with python best
   practices: use f-strings instead of %, use len() instead of
   __len__(), remove semicolons, use context managers for file
   operations, fix whitespace violations, extract magic strings into
   constants, remove unused imports and methods.

 - Fix small bugs in rvgen

   The generator scripts presented some corner case bugs: logical error
   in validating what a correct dot file looks like, fix an isinstance()
   check, enforce a dot file has an initial state, fix type annotations
   and typos in comments.

 - rvgen refactoring

   Refactor automata.py to use iterator-based parsing and handle
   required arguments directly in argparse.

 - Allow epoll in rtapp-sleep monitor

   The epoll_wait call is now rt-friendly so it should be allowed in the
   sleep monitor as a valid sleep method.

* tag 'trace-rv-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (32 commits)
  rv: Allow epoll in rtapp-sleep monitor
  rv/rvgen: fix _fill_states() return type annotation
  rv/rvgen: fix unbound loop variable warning
  rv/rvgen: enforce presence of initial state
  rv/rvgen: extract node marker string to class constant
  rv/rvgen: fix isinstance check in Variable.expand()
  rv/rvgen: make monitor arguments required in rvgen
  rv/rvgen: remove unused __get_main_name method
  rv/rvgen: remove unused sys import from dot2c
  rv/rvgen: refactor automata.py to use iterator-based parsing
  rv/rvgen: use class constant for init marker
  rv/rvgen: fix DOT file validation logic error
  rv/rvgen: fix PEP 8 whitespace violations
  rv/rvgen: fix typos in automata and generator docstring and comments
  rv/rvgen: use context managers for file operations
  rv/rvgen: remove unnecessary semicolons
  rv/rvgen: replace __len__() calls with len()
  rv/rvgen: replace % string formatting with f-strings
  rv/rvgen: remove bare except clauses in generator
  rv/rvgen: introduce AutomataError exception class
  ...
2026-04-15 17:15:18 -07:00
Eduard Zingerman
0251e40c48 bpf: copy BPF token from main program to subprograms
bpf_jit_subprogs() copies various fields from the main program's aux to
each subprogram's aux, but omits the BPF token. This causes
bpf_prog_kallsyms_add() to fail for subprograms loaded via BPF token,
as bpf_token_capable() falls back to capable() in init_user_ns when
token is NULL.

Copy prog->aux->token to func[i]->aux->token so that subprograms
inherit the same capability delegation as the main program.

Fixes: d79a354975 ("bpf: Consistently use BPF token throughout BPF verifier logic")
Signed-off-by: Tao Chen <ctao@meta.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260415-subprog-token-fix-v4-1-9bd000e8b068@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-15 16:46:47 -07:00
Linus Torvalds
e4bf304f00 ring-buffer updates for 7.1:
- Add remote buffers for pKVM
 
   pKVM has a hypervisor component that is used to protect the guest from the
   host kernel. This hypervisor is a black box to the kernel as the kernel is
   to user space. The remote buffers are used to have a memory mapping
   between the hypervisor and the kernel where kernel may send commands to
   enable tracing within the hypervisor. Then the kernel will read this
   memory mapping just like user space can read the memory mapped ring buffer
   of the kernel tracing system.
 
   Since the hypervisor only has a single context, it doesn't need to worry
   about races between normal context, interrupt context and NMIs like the
   kernel does. The ring buffer it uses doesn't need to be as complex. The
   remote buffers are a simple version of the ring buffer that works in a
   single context. They are still per-CPU and use sub buffers. The data
   layout is the same as the kernel's ring buffer to share the same parsing.
 
   Currently, only ARM64 implements pKVM, but there's work to implement it
   also in x86. The remote buffer code is separated out from the ARM
   implementation so that it can be used in the future by x86.
 
   The ARM64 updates for pKVM is in the ARM/KVM tree and it merged in the
   remote buffers of this tree.
 
 - Merge commit f35dbac694 ("ring-buffer: Fix to update per-subbuf entries of persistent ring buffer")`
 
   A fix was merged upstream that some new changes depended on. The upstream
   commit was merged into the ring buffer branch to fulfil the dependency.
 
 - Make the backup instance non reusable
 
   The backup instance is a copy of the persistent ring buffer so that the
   persistent ring buffer could start recording again without using the data
   from the previous boot. The backup isn't for normal tracing. It is made
   read-only, and after it is consumed, it is automatically removed.
 
 - Have backup copy persistent instance before it starts recording
 
   To allow the persistent ring buffer to start recording from the kernel
   command line commands, move the copy of the backup instance to before the
   the command line options start recording.
 
 - Report header_page overwrite field as "char" and not "int'
 
   The rust parser of the header_page file was triggering a warning when it
   defined the overwrite variable as "int" but it was only a single byte in
   size.
 
 - Fix memory barriers for the trace_buffer CPU mask
 
   When a CPU comes online, the bit is set to allow readers to know that the
   CPU buffer is allocated. The bit is set after the allocation is done, and
   a smp_wmb() is performed after the allocation and before the setting of
   the bit. But instead of adding a smp_rmb() to all readers, since once a
   buffer is created for a CPU it is not deleted if that CPU goes offline, so
   this allocation is almost always done at boot up before any readers exist.
 
   If for the unlikely case where a CPU comes online for the first time after
   the system boot has finished, send an IPI to all CPUs to force the
   smp_rmb() for each CPU.
 
 - Show clock function being used in debugging ring buffer data
 
   When the ring buffer checks are enabled and the ring buffer detects an
   inconsistency in the times of the invents, print out the clock being used
   when the error occurred. There was a very hard to hit bug that would
   happen every so often and it ended up being only triggered when the jiffies
   clock was being used. If the bug showed the clock being used, it would
   have been much easier to find the problem (which was an internal function
   was being traced which caused the clock accounting to go off).
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Merge tag 'trace-ringbuffer-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull ring-buffer updates from Steven Rostedt:

 - Add remote buffers for pKVM

   pKVM has a hypervisor component that is used to protect the guest
   from the host kernel. This hypervisor is a black box to the kernel as
   the kernel is to user space. The remote buffers are used to have a
   memory mapping between the hypervisor and the kernel where kernel may
   send commands to enable tracing within the hypervisor. Then the
   kernel will read this memory mapping just like user space can read
   the memory mapped ring buffer of the kernel tracing system.

   Since the hypervisor only has a single context, it doesn't need to
   worry about races between normal context, interrupt context and NMIs
   like the kernel does. The ring buffer it uses doesn't need to be as
   complex. The remote buffers are a simple version of the ring buffer
   that works in a single context. They are still per-CPU and use sub
   buffers. The data layout is the same as the kernel's ring buffer to
   share the same parsing.

   Currently, only ARM64 implements pKVM, but there's work to implement
   it also in x86. The remote buffer code is separated out from the ARM
   implementation so that it can be used in the future by x86.

   The ARM64 updates for pKVM is in the ARM/KVM tree and it merged in
   the remote buffers of this tree.

 - Make the backup instance non reusable

   The backup instance is a copy of the persistent ring buffer so that
   the persistent ring buffer could start recording again without using
   the data from the previous boot. The backup isn't for normal tracing.
   It is made read-only, and after it is consumed, it is automatically
   removed.

 - Have backup copy persistent instance before it starts recording

   To allow the persistent ring buffer to start recording from the
   kernel command line commands, move the copy of the backup instance to
   before the the command line options start recording.

 - Report header_page overwrite field as "char" and not "int'

   The rust parser of the header_page file was triggering a warning when
   it defined the overwrite variable as "int" but it was only a single
   byte in size.

 - Fix memory barriers for the trace_buffer CPU mask

   When a CPU comes online, the bit is set to allow readers to know that
   the CPU buffer is allocated. The bit is set after the allocation is
   done, and a smp_wmb() is performed after the allocation and before
   the setting of the bit. But instead of adding a smp_rmb() to all
   readers, since once a buffer is created for a CPU it is not deleted
   if that CPU goes offline, so this allocation is almost always done at
   boot up before any readers exist.

   If for the unlikely case where a CPU comes online for the first time
   after the system boot has finished, send an IPI to all CPUs to force
   the smp_rmb() for each CPU.

 - Show clock function being used in debugging ring buffer data

   When the ring buffer checks are enabled and the ring buffer detects
   an inconsistency in the times of the invents, print out the clock
   being used when the error occurred. There was a very hard to hit bug
   that would happen every so often and it ended up being only triggered
   when the jiffies clock was being used. If the bug showed the clock
   being used, it would have been much easier to find the problem (which
   was an internal function was being traced which caused the clock
   accounting to go off).

* tag 'trace-ringbuffer-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (26 commits)
  ring-buffer: Prevent off-by-one array access in ring_buffer_desc_page()
  ring-buffer: Report header_page overwrite as char
  tracing: Allow backup to save persistent ring buffer before it starts
  tracing/Documentation: Add a section about backup instance
  tracing: Remove the backup instance automatically after read
  tracing: Make the backup instance non-reusable
  ring-buffer: Enforce read ordering of trace_buffer cpumask and buffers
  ring-buffer: Show what clock function is used on timestamp errors
  tracing: Check for undefined symbols in simple_ring_buffer
  tracing: load/unload page callbacks for simple_ring_buffer
  Documentation: tracing: Add tracing remotes
  tracing: selftests: Add trace remote tests
  tracing: Add a trace remote module for testing
  tracing: Introduce simple_ring_buffer
  ring-buffer: Export buffer_data_page and macros
  tracing: Add helpers to create trace remote events
  tracing: Add events/ root files to trace remotes
  tracing: Add events to trace remotes
  tracing: Add init callback to trace remotes
  tracing: Add non-consuming read to trace remotes
  ...
2026-04-15 15:59:46 -07:00
Linus Torvalds
1521829632 ftrace updates for 7.1:
- Speed up ftrace_lookup_symbols() for single lookups
 
   The kallsyms lookup in ftrace_lookup_symbols() does a linear search over
   each symbol. This is fine when it must match multiple strings, but when
   there's only a single string being searched for, using a binary search is
   much more efficient. When a single string is passed in to search, use the
   binary search method.
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Merge tag 'ftrace-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull ftrace update from Steven Rostedt:

 - Speed up ftrace_lookup_symbols() for single lookups

   The kallsyms lookup in ftrace_lookup_symbols() does a linear search
   over each symbol. This is fine when it must match multiple strings,
   but when there's only a single string being searched for, using a
   binary search is much more efficient. When a single string is passed
   in to search, use the binary search method.

* tag 'ftrace-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ftrace: Use kallsyms binary search for single-symbol lookup
2026-04-15 15:57:11 -07:00
Linus Torvalds
aec2f682d4 This update includes the following changes:
API:
 
 - Replace crypto_get_default_rng with crypto_stdrng_get_bytes.
 - Remove simd skcipher support.
 - Allow algorithm types to be disabled when CRYPTO_SELFTESTS is off.
 
 Algorithms:
 
 - Remove CPU-based des/3des acceleration.
 - Add test vectors for authenc(hmac(md5),cbc(aes)).
 - Add test vectors for authenc(hmac(md5),cbc(des)).
 - Add test vectors for authenc(hmac(md5),rfc3686(ctr(aes))).
 - Add test vectors for authenc(hmac(sha1),rfc3686(ctr(aes))).
 - Add test vectors for authenc(hmac(sha224),rfc3686(ctr(aes))).
 - Add test vectors for authenc(hmac(sha256),rfc3686(ctr(aes))).
 - Add test vectors for authenc(hmac(sha384),rfc3686(ctr(aes))).
 - Add test vectors for authenc(hmac(sha512),rfc3686(ctr(aes))).
 - Replace spin lock with mutex in jitterentropy.
 
 Drivers:
 
 - Add authenc algorithms to safexcel.
 - Add support for zstd in qat.
 - Add wireless mode support for QAT GEN6.
 - Add anti-rollback support for QAT GEN6.
 - Add support for ctr(aes), gcm(aes), and ccm(aes) in dthev2.
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Merge tag 'v7.1-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

Pull crypto update from Herbert Xu:
 "API:
   - Replace crypto_get_default_rng with crypto_stdrng_get_bytes
   - Remove simd skcipher support
   - Allow algorithm types to be disabled when CRYPTO_SELFTESTS is off

  Algorithms:
   - Remove CPU-based des/3des acceleration
   - Add test vectors for authenc(hmac(md5),cbc({aes,des})) and
     authenc(hmac({md5,sha1,sha224,sha256,sha384,sha512}),rfc3686(ctr(aes)))
   - Replace spin lock with mutex in jitterentropy

  Drivers:
   - Add authenc algorithms to safexcel
   - Add support for zstd in qat
   - Add wireless mode support for QAT GEN6
   - Add anti-rollback support for QAT GEN6
   - Add support for ctr(aes), gcm(aes), and ccm(aes) in dthev2"

* tag 'v7.1-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (129 commits)
  crypto: af_alg - use sock_kmemdup in alg_setkey_by_key_serial
  crypto: vmx - remove CRYPTO_DEV_VMX from Kconfig
  crypto: omap - convert reqctx buffer to fixed-size array
  crypto: atmel-sha204a - add Thorsten Blum as maintainer
  crypto: atmel-ecc - add Thorsten Blum as maintainer
  crypto: qat - fix IRQ cleanup on 6xxx probe failure
  crypto: geniv - Remove unused spinlock from struct aead_geniv_ctx
  crypto: qce - simplify qce_xts_swapiv()
  crypto: hisilicon - Fix dma_unmap_single() direction
  crypto: talitos - rename first/last to first_desc/last_desc
  crypto: talitos - fix SEC1 32k ahash request limitation
  crypto: jitterentropy - replace long-held spinlock with mutex
  crypto: hisilicon - remove unused and non-public APIs for qm and sec
  crypto: hisilicon/qm - drop redundant variable initialization
  crypto: hisilicon/qm - remove else after return
  crypto: hisilicon/qm - add const qualifier to info_name in struct qm_cmd_dump_item
  crypto: hisilicon - fix the format string type error
  crypto: ccree - fix a memory leak in cc_mac_digest()
  crypto: qat - add support for zstd
  crypto: qat - use swab32 macro
  ...
2026-04-15 15:22:26 -07:00
Linus Torvalds
40286d6379 pci-v7.1-changes
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Merge tag 'pci-v7.1-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull pci updates from Bjorn Helgaas:
 "Enumeration:

   - Allow TLP Processing Hints to be enabled for RCiEPs (George Abraham
     P)

   - Enable AtomicOps only if we know the Root Port supports them (Gerd
     Bayer)

   - Don't enable AtomicOps for RCiEPs since none of them need Atomic
     Ops and we can't tell whether the Root Complex would support them
     (Gerd Bayer)

   - Leave Precision Time Measurement disabled until a driver enables it
     to avoid PCIe errors (Mika Westerberg)

   - Make pci_set_vga_state() fail if bridge doesn't support VGA
     routing, i.e., PCI_BRIDGE_CTL_VGA is not writable, and return
     errors to vga_get() callers including userspace via
     /dev/vga_arbiter (Simon Richter)

   - Validate max-link-speed from DT in j721e, brcmstb, mediatek-gen3,
     rzg3s drivers (where the actual controller constraints are known),
     and remove validation from the generic OF DT accessor (Hans Zhang)

   - Remove pc110pad driver (no longer useful after 486 CPU support
     removed) and no_pci_devices() (pc110pad was the last user) (Dmitry
     Torokhov, Heiner Kallweit)

  Resource management:

   - Prevent assigning space to unimplemented bridge windows; previously
     we mistakenly assumed prefetchable window existed and assigned
     space and put a BAR there (Ahmed Naseef)

   - Avoid shrinking bridge windows to fit in the initial Root Port
     window; fixes one problem with devices with large BARs connected
     via switches, e.g., Thunderbolt (Ilpo Järvinen)

   - Pass full extent of empty space, not just the aligned space, to
     resource_alignf callback so free space before the requested
     alignment can be used (Ilpo Järvinen)

   - Place small resources before larger ones for better utilization of
     address space (Ilpo Järvinen)

   - Fix alignment calculation for resource size larger than align,
     e.g., bridge windows larger than the 1MB required alignment (Ilpo
     Järvinen)

  Reset:

   - Update slot handling so all ARI functions are treated as being in
     the same slot. They're all reset by Secondary Bus Reset, but
     previously drivers of ARI functions that appeared to be on a
     non-zero device weren't notified and fatal hardware errors could
     result (Keith Busch)

   - Make sysfs reset_subordinate hotplug safe to avoid spurious hotplug
     events (Keith Busch)

   - Hide Secondary Bus Reset ('bus') from sysfs reset_methods if masked
     by CXL because it has no effect (Vidya Sagar)

   - Avoid FLR for AMD NPU device, where it causes the device to hang
     (Lizhi Hou)

  Error handling:

   - Clear only error bits in PCIe Device Status to avoid accidentally
     clearing Emergency Power Reduction Detected (Shuai Xue)

   - Check for AER errors even in devices without drivers (Lukas Wunner)

   - Initialize ratelimit info so DPC and EDR paths log AER error
     information (Kuppuswamy Sathyanarayanan)

  Power control:

   - Add UPD720201/UPD720202 USB 3.0 xHCI Host Controller .compatible so
     generic pwrctrl driver can control it (Neil Armstrong)

  Hotplug:

   - Set LED_HW_PLUGGABLE for NPEM hotplug-capable ports so LED core
     doesn't complain when setting brightness fails because the endpoint
     is gone (Richard Cheng)

  Peer-to-peer DMA:

   - Allow wildcards in list of host bridges that support peer-to-peer
     DMA between hierarchy domains and add all Google SoCs (Jacob
     Moroni)

  Endpoint framework:

   - Advertise dynamic inbound mapping support in pci-epf-test and
     update host pci_endpoint_test to skip doorbell testing if not
     advertised by endpoint (Koichiro Den)

   - Return 0, not remaining timeout, when MHI eDMA ops complete so
     mhi_ep_ring_add_element() doesn't interpret non-zero as failure
     (Daniel Hodges)

   - Remove vntb and ntb duplicate resource teardown that leads to oops
     when .allow_link() fails or .drop_link() is called (Koichiro Den)

   - Disable vntb delayed work before clearing BAR mappings and
     doorbells to avoid oops caused by doing the work after resources
     have been torn down (Koichiro Den)

   - Add a way to describe reserved subregions within BARs, e.g.,
     platform-owned fixed register windows, and use it for the RK3588
     BAR4 DMA ctrl window (Koichiro Den)

   - Add BAR_DISABLED for BARs that will never be available to an EPF
     driver, and change some BAR_RESERVED annotations to BAR_DISABLED
     (Niklas Cassel)

   - Add NTB .get_dma_dev() callback for cases where DMA API requires a
     different device, e.g., vNTB devices (Koichiro Den)

   - Add reserved region types for MSI-X Table and PBA so Endpoint
     controllers can them as describe hardware-owned regions in a
     BAR_RESERVED BAR (Manikanta Maddireddy)

   - Make Tegra194/234 BAR0 programmable and remove 1MB size limit
     (Manikanta Maddireddy)

   - Expose Tegra BAR2 (MSI-X) and BAR4 (DMA) as 64-bit BAR_RESERVED
     (Manikanta Maddireddy)

   - Add Tegra194 and Tegra234 device table entries to pci_endpoint_test
     (Manikanta Maddireddy)

   - Skip the BAR subrange selftest if there are not enough inbound
     window resources to run the test (Christian Bruel)

  New native PCIe controller drivers:

   - Add DT binding and driver for Andes QiLai SoC PCIe host controller
     (Randolph Lin)

   - Add DT binding and driver for ESWIN PCIe Root Complex (Senchuan
     Zhang)

  Baikal T-1 PCIe controller driver:

   - Remove driver since it never quite became usable (Andy Shevchenko)

  Cadence PCIe controller driver:

   - Implement byte/word config reads with dword (32-bit) reads because
     some Cadence controllers don't support sub-dword accesses (Aksh
     Garg)

  CIX Sky1 PCIe controller driver:

   - Add 'power-domains' to DT binding for SCMI power domain (Gary Yang)

  Freescale i.MX6 PCIe controller driver:

   - Add i.MX94 and i.MX943 to fsl,imx6q-pcie-ep DT binding (Richard
     Zhu)

   - Delay instead of polling for L2/L3 Ready after PME_Turn_off when
     suspending i.MX6SX because LTSSM registers are inaccessible
     (Richard Zhu)

   - Separate PERST# assertion (for resetting endpoints) from core reset
     (for resetting the RC itself) to prepare for new DTs with PERST#
     GPIO in per-Root Port nodes (Sherry Sun)

   - Retain Root Port MSI capability on i.MX7D, i.MX8MM, and i.MX8MQ so
     MSI from downstream devices will work (Richard Zhu)

   - Fix i.MX95 reference clock source selection when internal refclk is
     used (Franz Schnyder)

  Freescale Layerscape PCIe controller driver:

   - Allow building as a removable module (Sascha Hauer)

  MediaTek PCIe Gen3 controller driver:

   - Use dev_err_probe() to simplify error paths and make deferred probe
     messages visible in /sys/kernel/debug/devices_deferred (Chen-Yu
     Tsai)

   - Power off device if setup fails (Chen-Yu Tsai)

   - Integrate new pwrctrl API to enable power control for WiFi/BT
     adapters on mainboard or in PCIe or M.2 slots (Chen-Yu Tsai)

  NVIDIA Tegra194 PCIe controller driver:

   - Poll less aggressively and non-atomically for PME_TO_Ack during
     transition to L2 (Vidya Sagar)

   - Disable LTSSM after transition to Detect on surprise link down to
     stop toggling between Polling and Detect (Manikanta Maddireddy)

   - Don't force the device into the D0 state before L2 when suspending
     or shutting down the controller (Vidya Sagar)

   - Disable PERST# IRQ only in Endpoint mode because it's not
     registered in Root Port mode (Manikanta Maddireddy)

   - Handle 'nvidia,refclk-select' as optional (Vidya Sagar)

   - Disable direct speed change in Endpoint mode so link speed change
     is controlled by the host (Vidya Sagar)

   - Set LTR values before link up to avoid bogus LTR messages with 0
     latency (Vidya Sagar)

   - Allow system suspend when the Endpoint link is down (Vidya Sagar)

   - Use DWC IP core version, not Tegra custom values, to avoid DWC core
     version check warnings (Manikanta Maddireddy)

   - Apply ECRC workaround to devices based on DesignWare 5.00a as well
     as 4.90a (Manikanta Maddireddy)

   - Disable PM Substate L1.2 in Endpoint mode to work around Tegra234
     erratum (Vidya Sagar)

   - Delay post-PERST# cleanup until core is powered on to avoid CBB
     timeout (Manikanta Maddireddy)

   - Assert CLKREQ# so switches that forward it to their downstream side
     can bring up those links successfully (Vidya Sagar)

   - Calibrate pipe to UPHY for Endpoint mode to reset stale PLL state
     from any previous bad link state (Vidya Sagar)

   - Remove IRQF_ONESHOT flag from Endpoint interrupt registration so
     DMA driver and Endpoint controller driver can share the interrupt
     line (Vidya Sagar)

   - Enable DMA interrupt to support DMA in both Root Port and Endpoint
     modes (Vidya Sagar)

   - Enable hardware link retraining after link goes down in Endpoint
     mode (Vidya Sagar)

   - Add DT binding and driver support for core clock monitoring (Vidya
     Sagar)

  Qualcomm PCIe controller driver:

   - Advertise 'Hot-Plug Capable' and set 'No Command Completed Support'
     since Qcom Root Ports support hotplug events like DL_Up/Down and
     can accept writes to Slot Control without delays between writes
     (Krishna Chaitanya Chundru)

  Renesas R-Car PCIe controller driver:

   - Mark Endpoint BAR0 and BAR2 as Resizable (Koichiro Den)

   - Reduce EPC BAR alignment requirement to 4K (Koichiro Den)

  Renesas RZ/G3S PCIe controller driver:

   - Add RZ/G3E to DT binding and to driver (John Madieu)

   - Assert (not deassert) resets in probe error path (John Madieu)

   - Assert resets in suspend path in reverse order they were deasserted
     during probe (John Madieu)

   - Rework inbound window algorithm to prevent mapping more than
     intended region and enforce alignment on size, to prepare for
     RZ/G3E support (John Madieu)

  Rockchip DesignWare PCIe controller driver:

   - Add tracepoints for PCIe controller LTSSM transitions and link rate
     changes (Shawn Lin)

   - Trace LTSSM events collected by the dw-rockchip debug FIFO (Shawn
     Lin)

  SOPHGO PCIe controller driver:

   - Disable ASPM L0s and L1 on Sophgo 2042 PCIe Root Ports that
     advertise support for them (Yao Zi)

  Synopsys DesignWare PCIe controller driver:

   - Continue with system suspend even if an Endpoint doesn't respond
     with PME_TO_Ack message (Manivannan Sadhasivam)

   - Set Endpoint MSI-X Table Size in the correct function of a
     multi-function device when configuring MSI-X, not in Function 0
     (Aksh Garg)

   - Set Max Link Width and Max Link Speed for all functions of a
     multi-function device, not just Function 0 (Aksh Garg)

   - Expose PCIe event counters in groups 5-7 in debugfs (Hans Zhang)

  Miscellaneous:

   - Warn only once about invalid ACS kernel parameter format (Richard
     Cheng)

   - Suppress FW_BUG warning when writing sysfs 'numa_node' with the
     current value (Li RongQing)

   - Drop redundant 'depends on PCI' from Kconfig (Julian Braha)"

* tag 'pci-v7.1-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (165 commits)
  PCI/P2PDMA: Add Google SoCs to the P2P DMA host bridge list
  PCI/P2PDMA: Allow wildcard Device IDs in host bridge list
  PCI: sg2042: Avoid L0s and L1 on Sophgo 2042 PCIe Root Ports
  PCI: cadence: Add flags for disabling ASPM capability for broken Root Ports
  PCI: tegra194: Add core monitor clock support
  dt-bindings: PCI: tegra194: Add monitor clock support
  PCI: tegra194: Enable hardware hot reset mode in Endpoint mode
  PCI: tegra194: Enable DMA interrupt
  PCI: tegra194: Remove IRQF_ONESHOT flag during Endpoint interrupt registration
  PCI: tegra194: Calibrate pipe to UPHY for Endpoint mode
  PCI: tegra194: Assert CLKREQ# explicitly by default
  PCI: tegra194: Fix CBB timeout caused by DBI access before core power-on
  PCI: tegra194: Disable L1.2 capability of Tegra234 EP
  PCI: dwc: Apply ECRC workaround to DesignWare 5.00a as well
  PCI: tegra194: Use DWC IP core version
  PCI: tegra194: Free up Endpoint resources during remove()
  PCI: tegra194: Allow system suspend when the Endpoint link is not up
  PCI: tegra194: Set LTR message request before PCIe link up in Endpoint mode
  PCI: tegra194: Disable direct speed change for Endpoint mode
  PCI: tegra194: Use devm_gpiod_get_optional() to parse "nvidia,refclk-select"
  ...
2026-04-15 14:41:21 -07:00
Linus Torvalds
334fbe734e mm.git review status for linus..mm-stable
Everything:
 
 Total patches:       368
 Reviews/patch:       1.56
 Reviewed rate:       74%
 
 Excluding DAMON:
 
 Total patches:       316
 Reviews/patch:       1.77
 Reviewed rate:       81%
 
 Excluding DAMON and zram:
 
 Total patches:       306
 Reviews/patch:       1.81
 Reviewed rate:       82%
 
 Excluding DAMON, zram and maple_tree:
 
 Total patches:       276
 Reviews/patch:       2.01
 Reviewed rate:       91%
 
 Significant patch series in this merge:
 
 - The 30 patch series "maple_tree: Replace big node with maple copy"
   from Liam Howlett is mainly prepararatory work for ongoing development
   but it does reduce stack usage and is an improvement.
 
 - The 12 patch series "mm, swap: swap table phase III: remove swap_map"
   from Kairui Song offers memory savings by removing the static swap_map.
   It also yields some CPU savings and implements several cleanups.
 
 - The 2 patch series "mm: memfd_luo: preserve file seals" from Pratyush
   Yadav adds file seal preservation to LUO's memfd code.
 
 - The 2 patch series "mm: zswap: add per-memcg stat for incompressible
   pages" from Jiayuan Chen adds additional userspace stats reportng to
   zswap.
 
 - The 4 patch series "arch, mm: consolidate empty_zero_page" from Mike
   Rapoport implements some cleanups for our handling of ZERO_PAGE() and
   zero_pfn.
 
 - The 2 patch series "mm/kmemleak: Improve scan_should_stop()
   implementation" from Zhongqiu Han provides an robustness improvement and
   some cleanups in the kmemleak code.
 
 - The 4 patch series "Improve khugepaged scan logic" from Vernon Yang
   "improves the khugepaged scan logic and reduces CPU consumption by
   prioritizing scanning tasks that access memory frequently".
 
 - The 2 patch series "Make KHO Stateless" from Jason Miu simplifies
   Kexec Handover by "transitioning KHO from an xarray-based metadata
   tracking system with serialization to a radix tree data structure that
   can be passed directly to the next kernel"
 
 - The 3 patch series "mm: vmscan: add PID and cgroup ID to vmscan
   tracepoints" from Thomas Ballasi and Steven Rostedt enhances vmscan's
   tracepointing.
 
 - The 5 patch series "mm: arch/shstk: Common shadow stack mapping helper
   and VM_NOHUGEPAGE" from Catalin Marinas is a cleanup for the shadow
   stack code: remove per-arch code in favour of a generic implementation.
 
 - The 2 patch series "Fix KASAN support for KHO restored vmalloc
   regions" from Pasha Tatashin fixes a WARN() which can be emitted the KHO
   restores a vmalloc area.
 
 - The 4 patch series "mm: Remove stray references to pagevec" from Tal
   Zussman provides several cleanups, mainly udpating references to "struct
   pagevec", which became folio_batch three years ago.
 
 - The 17 patch series "mm: Eliminate fake head pages from vmemmap
   optimization" from Kiryl Shutsemau simplifies the HugeTLB vmemmap
   optimization (HVO) by changing how tail pages encode their relationship
   to the head page.
 
 - The 2 patch series "mm/damon/core: improve DAMOS quota efficiency for
   core layer filters" from SeongJae Park improves two problematic
   behaviors of DAMOS that makes it less efficient when core layer filters
   are used.
 
 - The 3 patch series "mm/damon: strictly respect min_nr_regions" from
   SeongJae Park improves DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter.
 
 - The 3 patch series "mm/page_alloc: pcp locking cleanup" from Vlastimil
   Babka is a proper fix for a previously hotfixed SMP=n issue.  Code
   simplifications and cleanups ennsed.
 
 - The 16 patch series "mm: cleanups around unmapping / zapping" from
   David Hildenbrand implements "a bunch of cleanups around unmapping and
   zapping.  Mostly simplifications, code movements, documentation and
   renaming of zapping functions".
 
 - The 6 patch series "support batched checking of the young flag for
   MGLRU" from Baolin Wang supports batched checking of the young flag for
   MGLRU.  It's part cleanups; one benchmark shows large performance
   benefits for arm64.
 
 - The 5 patch series "memcg: obj stock and slab stat caching cleanups"
   from Johannes Weiner provides memcg cleanup and robustness improvements.
 
 - The 5 patch series "Allow order zero pages in page reporting" from
   Yuvraj Sakshith enhances page_reporting's free page reporting - it is
   presently and undesirably order-0 pages when reporting free memory.
 
 - The 6 patch series "mm: vma flag tweaks" from Lorenzo Stoakes is
   cleanup work following from the recent conversion of the VMA flags to a
   bitmap.
 
 - The 10 patch series "mm/damon: add optional debugging-purpose sanity
   checks" from SeongJae Park adds some more developer-facing debug checks
   into DAMON core.
 
 - The 2 patch series "mm/damon: test and document power-of-2
   min_region_sz requirement" from SeongJae Park adds an additional DAMON
   kunit test and makes some adjustments to the addr_unit parameter
   handling.
 
 - The 3 patch series "mm/damon/core: make passed_sample_intervals
   comparisons overflow-safe" from SeongJae Park fixes a hard-to-hit time
   overflow issue in DAMON core.
 
 - The 7 patch series "mm/damon: improve/fixup/update ratio calculation,
   test and documentation" from SeongJae Park is a "batch of misc/minor
   improvements and fixups" for DAMON.
 
 - The 4 patch series "mm: move vma_(kernel|mmu)_pagesize() out of
   hugetlb.c" from David Hildenbrand fixes a possible issue with dax-device
   when CONFIG_HUGETLB=n.  Some code movement was required.
 
 - The 6 patch series "zram: recompression cleanups and tweaks" from
   Sergey Senozhatsky provides "a somewhat random mix of fixups,
   recompression cleanups and improvements" in the zram code.
 
 - The 11 patch series "mm/damon: support multiple goal-based quota
   tuning algorithms" from SeongJae Park extend DAMOS quotas goal
   auto-tuning to support multiple tuning algorithms that users can select.
 
 - The 4 patch series "mm: thp: reduce unnecessary
   start_stop_khugepaged()" from Breno Leitao fixes the khugpaged sysfs
   handling so we no longer spam the logs with reams of junk when
   starting/stopping khugepaged.
 
 - The 3 patch series "mm: improve map count checks" from Lorenzo Stoakes
   provides some cleanups and slight fixes in the mremap, mmap and vma
   code.
 
 - The 5 patch series "mm/damon: support addr_unit on default monitoring
   targets for modules" from SeongJae Park extends the use of DAMON core's
   addr_unit tunable.
 
 - The 5 patch series "mm: khugepaged cleanups and mTHP prerequisites"
   from Nico Pache provides cleanups in the khugepaged and is a base for
   Nico's planned khugepaged mTHP support.
 
 - The 15 patch series "mm: memory hot(un)plug and SPARSEMEM cleanups"
   from David Hildenbrand implements code movement and cleanups in the
   memhotplug and sparsemem code.
 
 - The 2 patch series "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and
   cleanup CONFIG_MIGRATION" from David Hildenbrand rationalizes some
   memhotplug Kconfig support.
 
 - The 6 patch series "change young flag check functions to return bool"
   from Baolin Wang is "a cleanup patchset to change all young flag check
   functions to return bool".
 
 - The 3 patch series "mm/damon/sysfs: fix memory leak and NULL
   dereference issues" from Josh Law and SeongJae Park fixes a few
   potential DAMON bugs.
 
 - The 25 patch series "mm/vma: convert vm_flags_t to vma_flags_t in vma
   code" from "converts a lot of the existing use of the legacy vm_flags_t
   data type to the new vma_flags_t type which replaces it".  Mainly in the
   vma code.
 
 - The 21 patch series "mm: expand mmap_prepare functionality and usage"
   from Lorenzo Stoakes "expands the mmap_prepare functionality, which is
   intended to replace the deprecated f_op->mmap hook which has been the
   source of bugs and security issues for some time".  Cleanups,
   documentation, extension of mmap_prepare into filesystem drivers.
 
 - The 13 patch series "mm/huge_memory: refactor zap_huge_pmd()" from
   Lorenzo Stoakes simplifies and cleans up zap_huge_pmd().  Additional
   cleanups around vm_normal_folio_pmd() and the softleaf functionality are
   performed.
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Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "maple_tree: Replace big node with maple copy" (Liam Howlett)

   Mainly prepararatory work for ongoing development but it does reduce
   stack usage and is an improvement.

 - "mm, swap: swap table phase III: remove swap_map" (Kairui Song)

   Offers memory savings by removing the static swap_map. It also yields
   some CPU savings and implements several cleanups.

 - "mm: memfd_luo: preserve file seals" (Pratyush Yadav)

   File seal preservation to LUO's memfd code

 - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
   Chen)

   Additional userspace stats reportng to zswap

 - "arch, mm: consolidate empty_zero_page" (Mike Rapoport)

   Some cleanups for our handling of ZERO_PAGE() and zero_pfn

 - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
   Han)

   A robustness improvement and some cleanups in the kmemleak code

 - "Improve khugepaged scan logic" (Vernon Yang)

   Improve khugepaged scan logic and reduce CPU consumption by
   prioritizing scanning tasks that access memory frequently

 - "Make KHO Stateless" (Jason Miu)

   Simplify Kexec Handover by transitioning KHO from an xarray-based
   metadata tracking system with serialization to a radix tree data
   structure that can be passed directly to the next kernel

 - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
   Ballasi and Steven Rostedt)

   Enhance vmscan's tracepointing

 - "mm: arch/shstk: Common shadow stack mapping helper and
   VM_NOHUGEPAGE" (Catalin Marinas)

   Cleanup for the shadow stack code: remove per-arch code in favour of
   a generic implementation

 - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)

   Fix a WARN() which can be emitted the KHO restores a vmalloc area

 - "mm: Remove stray references to pagevec" (Tal Zussman)

   Several cleanups, mainly udpating references to "struct pagevec",
   which became folio_batch three years ago

 - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
   Shutsemau)

   Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
   pages encode their relationship to the head page

 - "mm/damon/core: improve DAMOS quota efficiency for core layer
   filters" (SeongJae Park)

   Improve two problematic behaviors of DAMOS that makes it less
   efficient when core layer filters are used

 - "mm/damon: strictly respect min_nr_regions" (SeongJae Park)

   Improve DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter

 - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)

   The proper fix for a previously hotfixed SMP=n issue. Code
   simplifications and cleanups ensued

 - "mm: cleanups around unmapping / zapping" (David Hildenbrand)

   A bunch of cleanups around unmapping and zapping. Mostly
   simplifications, code movements, documentation and renaming of
   zapping functions

 - "support batched checking of the young flag for MGLRU" (Baolin Wang)

   Batched checking of the young flag for MGLRU. It's part cleanups; one
   benchmark shows large performance benefits for arm64

 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)

   memcg cleanup and robustness improvements

 - "Allow order zero pages in page reporting" (Yuvraj Sakshith)

   Enhance free page reporting - it is presently and undesirably order-0
   pages when reporting free memory.

 - "mm: vma flag tweaks" (Lorenzo Stoakes)

   Cleanup work following from the recent conversion of the VMA flags to
   a bitmap

 - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
   Park)

   Add some more developer-facing debug checks into DAMON core

 - "mm/damon: test and document power-of-2 min_region_sz requirement"
   (SeongJae Park)

   An additional DAMON kunit test and makes some adjustments to the
   addr_unit parameter handling

 - "mm/damon/core: make passed_sample_intervals comparisons
   overflow-safe" (SeongJae Park)

   Fix a hard-to-hit time overflow issue in DAMON core

 - "mm/damon: improve/fixup/update ratio calculation, test and
   documentation" (SeongJae Park)

   A batch of misc/minor improvements and fixups for DAMON

 - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
   Hildenbrand)

   Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
   movement was required.

 - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)

   A somewhat random mix of fixups, recompression cleanups and
   improvements in the zram code

 - "mm/damon: support multiple goal-based quota tuning algorithms"
   (SeongJae Park)

   Extend DAMOS quotas goal auto-tuning to support multiple tuning
   algorithms that users can select

 - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)

   Fix the khugpaged sysfs handling so we no longer spam the logs with
   reams of junk when starting/stopping khugepaged

 - "mm: improve map count checks" (Lorenzo Stoakes)

   Provide some cleanups and slight fixes in the mremap, mmap and vma
   code

 - "mm/damon: support addr_unit on default monitoring targets for
   modules" (SeongJae Park)

   Extend the use of DAMON core's addr_unit tunable

 - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)

   Cleanups to khugepaged and is a base for Nico's planned khugepaged
   mTHP support

 - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)

   Code movement and cleanups in the memhotplug and sparsemem code

 - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
   CONFIG_MIGRATION" (David Hildenbrand)

   Rationalize some memhotplug Kconfig support

 - "change young flag check functions to return bool" (Baolin Wang)

   Cleanups to change all young flag check functions to return bool

 - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
   Law and SeongJae Park)

   Fix a few potential DAMON bugs

 - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
   Stoakes)

   Convert a lot of the existing use of the legacy vm_flags_t data type
   to the new vma_flags_t type which replaces it. Mainly in the vma
   code.

 - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)

   Expand the mmap_prepare functionality, which is intended to replace
   the deprecated f_op->mmap hook which has been the source of bugs and
   security issues for some time. Cleanups, documentation, extension of
   mmap_prepare into filesystem drivers

 - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)

   Simplify and clean up zap_huge_pmd(). Additional cleanups around
   vm_normal_folio_pmd() and the softleaf functionality are performed.

* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm: fix deferred split queue races during migration
  mm/khugepaged: fix issue with tracking lock
  mm/huge_memory: add and use has_deposited_pgtable()
  mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
  mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
  mm/huge_memory: separate out the folio part of zap_huge_pmd()
  mm/huge_memory: use mm instead of tlb->mm
  mm/huge_memory: remove unnecessary sanity checks
  mm/huge_memory: deduplicate zap deposited table call
  mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
  mm/huge_memory: add a common exit path to zap_huge_pmd()
  mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
  mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
  mm/huge: avoid big else branch in zap_huge_pmd()
  mm/huge_memory: simplify vma_is_specal_huge()
  mm: on remap assert that input range within the proposed VMA
  mm: add mmap_action_map_kernel_pages[_full]()
  uio: replace deprecated mmap hook with mmap_prepare in uio_info
  drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
  mm: allow handling of stacked mmap_prepare hooks in more drivers
  ...
2026-04-15 12:59:16 -07:00
Alexei Starovoitov
4fddde2a73 bpf: Fix use-after-free in arena_vm_close on fork
arena_vm_open() only bumps vml->mmap_count but never registers the
child VMA in arena->vma_list. The vml->vma always points at the
parent VMA, so after parent munmap the pointer dangles. If the child
then calls bpf_arena_free_pages(), zap_pages() reads the stale
vml->vma triggering use-after-free.

Fix this by preventing the arena VMA from being inherited across
fork with VM_DONTCOPY, and preventing VMA splits via the may_split
callback.

Also reject mremap with a .mremap callback returning -EINVAL. A
same-size mremap(MREMAP_FIXED) on the full arena VMA reaches
copy_vma() through the following path:

  check_prep_vma()       - returns 0 early: new_len == old_len
                           skips VM_DONTEXPAND check
  prep_move_vma()        - vm_start == old_addr and
                           vm_end == old_addr + old_len
                           so may_split is never called
  move_vma()
    copy_vma_and_data()
      copy_vma()
        vm_area_dup()    - copies vm_private_data (vml pointer)
        vm_ops->open()   - bumps vml->mmap_count
      vm_ops->mremap()   - returns -EINVAL, rollback unmaps new VMA

The refcount ensures the rollback's arena_vm_close does not free
the vml shared with the original VMA.

Reported-by: Weiming Shi <bestswngs@gmail.com>
Reported-by: Xiang Mei <xmei5@asu.edu>
Fixes: 317460317a ("bpf: Introduce bpf_arena.")
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260413194245.21449-1-alexei.starovoitov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-15 12:08:55 -07:00
Linus Torvalds
5bdb4078e1 sched_ext: Changes for v7.1
- Cgroup sub-scheduler groundwork. Multiple BPF schedulers can be
   attached to cgroups and the dispatch path is made hierarchical. This
   involves substantial restructuring of the core dispatch, bypass,
   watchdog, and dump paths to be per-scheduler, along with new
   infrastructure for scheduler ownership enforcement, lifecycle
   management, and cgroup subtree iteration. The enqueue path is not yet
   updated and will follow in a later cycle.
 
 - scx_bpf_dsq_reenq() generalized to support any DSQ including remote
   local DSQs and user DSQs. Built on top of this, SCX_ENQ_IMMED
   guarantees that tasks dispatched to local DSQs either run immediately
   or get reenqueued back through ops.enqueue(), giving schedulers tighter
   control over queueing latency. Also useful for opportunistic CPU
   sharing across sub-schedulers.
 
 - ops.dequeue() was only invoked when the core knew a task was in BPF
   data structures, missing scheduling property change events and skipping
   callbacks for non-local DSQ dispatches from ops.select_cpu(). Fixed to
   guarantee exactly one ops.dequeue() call when a task leaves BPF
   scheduler custody.
 
 - Kfunc access validation moved from runtime to BPF verifier time,
   removing runtime mask enforcement.
 
 - Idle SMT sibling prioritization in the idle CPU selection path.
 
 - Documentation, selftest, and tooling updates. Misc bug fixes and
   cleanups.
 
 - Merges from tip/sched-core, cgroup/for-7.1, and for-7.0-fixes to
   resolve dependencies and conflicts for the above changes.
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Merge tag 'sched_ext-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext

Pull sched_ext updates from Tejun Heo:

 - cgroup sub-scheduler groundwork

   Multiple BPF schedulers can be attached to cgroups and the dispatch
   path is made hierarchical. This involves substantial restructuring of
   the core dispatch, bypass, watchdog, and dump paths to be
   per-scheduler, along with new infrastructure for scheduler ownership
   enforcement, lifecycle management, and cgroup subtree iteration

   The enqueue path is not yet updated and will follow in a later cycle

 - scx_bpf_dsq_reenq() generalized to support any DSQ including remote
   local DSQs and user DSQs

   Built on top of this, SCX_ENQ_IMMED guarantees that tasks dispatched
   to local DSQs either run immediately or get reenqueued back through
   ops.enqueue(), giving schedulers tighter control over queueing
   latency

   Also useful for opportunistic CPU sharing across sub-schedulers

 - ops.dequeue() was only invoked when the core knew a task was in BPF
   data structures, missing scheduling property change events and
   skipping callbacks for non-local DSQ dispatches from ops.select_cpu()

   Fixed to guarantee exactly one ops.dequeue() call when a task leaves
   BPF scheduler custody

 - Kfunc access validation moved from runtime to BPF verifier time,
   removing runtime mask enforcement

 - Idle SMT sibling prioritization in the idle CPU selection path

 - Documentation, selftest, and tooling updates. Misc bug fixes and
   cleanups

* tag 'sched_ext-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext: (134 commits)
  tools/sched_ext: Add explicit cast from void* in RESIZE_ARRAY()
  sched_ext: Make string params of __ENUM_set() const
  tools/sched_ext: Kick home CPU for stranded tasks in scx_qmap
  sched_ext: Drop spurious warning on kick during scheduler disable
  sched_ext: Warn on task-based SCX op recursion
  sched_ext: Rename scx_kf_allowed_on_arg_tasks() to scx_kf_arg_task_ok()
  sched_ext: Remove runtime kfunc mask enforcement
  sched_ext: Add verifier-time kfunc context filter
  sched_ext: Drop redundant rq-locked check from scx_bpf_task_cgroup()
  sched_ext: Decouple kfunc unlocked-context check from kf_mask
  sched_ext: Fix ops.cgroup_move() invocation kf_mask and rq tracking
  sched_ext: Track @p's rq lock across set_cpus_allowed_scx -> ops.set_cpumask
  sched_ext: Add select_cpu kfuncs to scx_kfunc_ids_unlocked
  sched_ext: Drop TRACING access to select_cpu kfuncs
  selftests/sched_ext: Fix wrong DSQ ID in peek_dsq error message
  sched_ext: Documentation: improve accuracy of task lifecycle pseudo-code
  selftests/sched_ext: Improve runner error reporting for invalid arguments
  sched_ext: Documentation: Fix scx_bpf_move_to_local kfunc name
  sched_ext: Documentation: Add ops.dequeue() to task lifecycle
  tools/sched_ext: Fix off-by-one in scx_sdt payload zeroing
  ...
2026-04-15 10:54:24 -07:00
Linus Torvalds
7de6b4a246 workqueue: Changes for v7.1
- New default WQ_AFFN_CACHE_SHARD affinity scope subdivides LLCs into
   smaller shards to improve scalability on machines with many CPUs per
   LLC.
 
 - Misc: system_dfl_long_wq for long unbound works, devm_alloc_workqueue()
   for device-managed allocation, sysfs exposure for ordered workqueues and
   the EFI workqueue, removal of HK_TYPE_WQ from wq_unbound_cpumask, and
   various small fixes.
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Merge tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue updates from Tejun Heo:

 - New default WQ_AFFN_CACHE_SHARD affinity scope subdivides LLCs into
   smaller shards to improve scalability on machines with many CPUs per
   LLC

 - Misc:
    - system_dfl_long_wq for long unbound works
    - devm_alloc_workqueue() for device-managed allocation
    - sysfs exposure for ordered workqueues and the EFI workqueue
    - removal of HK_TYPE_WQ from wq_unbound_cpumask
    - various small fixes

* tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (21 commits)
  workqueue: validate cpumask_first() result in llc_populate_cpu_shard_id()
  workqueue: use NR_STD_WORKER_POOLS instead of hardcoded value
  workqueue: avoid unguarded 64-bit division
  docs: workqueue: document WQ_AFFN_CACHE_SHARD affinity scope
  workqueue: add test_workqueue benchmark module
  tools/workqueue: add CACHE_SHARD support to wq_dump.py
  workqueue: set WQ_AFFN_CACHE_SHARD as the default affinity scope
  workqueue: add WQ_AFFN_CACHE_SHARD affinity scope
  workqueue: fix typo in WQ_AFFN_SMT comment
  workqueue: Remove HK_TYPE_WQ from affecting wq_unbound_cpumask
  workqueue: unlink pwqs from wq->pwqs list in alloc_and_link_pwqs() error path
  workqueue: Remove NULL wq WARN in __queue_delayed_work()
  workqueue: fix parse_affn_scope() prefix matching bug
  workqueue: devres: Add device-managed allocate workqueue
  workqueue: Add system_dfl_long_wq for long unbound works
  tools/workqueue/wq_dump.py: add NODE prefix to all node columns
  tools/workqueue/wq_dump.py: fix column alignment in node_nr/max_active section
  tools/workqueue/wq_dump.py: remove backslash separator from node_nr/max_active header
  efi: Allow to expose the workqueue via sysfs
  workqueue: Allow to expose ordered workqueues via sysfs
  ...
2026-04-15 10:32:08 -07:00
Linus Torvalds
b71f0be2d2 cgroup: Changes for v7.1
- cgroup_file_notify() locking converted from a global lock to
   per-cgroup_file spinlock with a lockless fast-path when no notification
   is needed.
 
 - Misc changes including exposing cgroup helpers for sched_ext and minor
   fixes.
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Merge tag 'cgroup-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull cgroup updates from Tejun Heo:

 - cgroup_file_notify() locking converted from a global lock to
   per-cgroup_file spinlock with a lockless fast-path when no
   notification is needed

 - Misc changes including exposing cgroup helpers for sched_ext and
   minor fixes

* tag 'cgroup-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup/rdma: fix swapped arguments in pr_warn() format string
  cgroup/dmem: remove region parameter from dmemcg_parse_limit
  cgroup: replace global cgroup_file_kn_lock with per-cgroup_file lock
  cgroup: add lockless fast-path checks to cgroup_file_notify()
  cgroup: reduce cgroup_file_kn_lock hold time in cgroup_file_notify()
  cgroup: Expose some cgroup helpers
2026-04-15 10:18:49 -07:00
Eduard Zingerman
ecdd4fd8a5 bpf: fix arg tracking for imprecise/multi-offset BPF_ST/STX
BPF_STX through ARG_IMPRECISE dst should be recognized as a local
spill and join at_stack with the written value. For example,
consider the following situation:

   // r1 = ARG_IMPRECISE{mask=BIT(0)|BIT(1)}
   *(u64 *)(r1 + 0) = r8

Here the analysis should produce an equivalent of

  at_stack[*] = join(old, r8)

BPF_ST through multi-offset or imprecise dst should join at_stack with
none instead of overwriting the slots. For example, consider the
following situation:

   // r1 = ARG_IMPRECISE{mask=BIT(0)|BIT(1)}
   *(u64 *)(r1 + 0) = 0

Here the analysis should produce an equivalent of

  at_stack[*r1] = join(old, none).

Move the definition of the clear_overlapping_stack_slots() in order to
have __arg_track_join() visible. Remove the OFF_IMPRECISE constant to
avoid having two ways to express imprecise offset.
Only 'offset-imprecise {frame=N, cnt=0}' remains.

Fixes: bf0c571f7f ("bpf: introduce forward arg-tracking dataflow analysis")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260413-stacklive-fixes-v2-1-398e126e5cf3@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-15 08:40:47 -07:00
Yiyang Chen
16c4f0211a taskstats: set version in TGID exit notifications
delay accounting started populating taskstats records with a valid version
field via fill_pid() and fill_tgid().

Later, commit ad4ecbcba7 ("[PATCH] delay accounting taskstats interface
send tgid once") changed the TGID exit path to send the cached
signal->stats aggregate directly instead of building the outgoing record
through fill_tgid().  Unlike fill_tgid(), fill_tgid_exit() only
accumulates accounting data and never initializes stats->version.

As a result, TGID exit notifications can reach userspace with version == 0
even though PID exit notifications and TASKSTATS_CMD_GET replies carry a
valid taskstats version.

This is easy to reproduce with `tools/accounting/getdelays.c`.

I have a small follow-up patch for that tool which:

1. increases the receive buffer/message size so the pid+tgid
   combined exit notification is not dropped/truncated

2. prints `stats->version`.

With that patch, the reproducer is:

  Terminal 1:
    ./getdelays -d -v -l -m 0

  Terminal 2:
    taskset -c 0 python3 -c 'import threading,time; t=threading.Thread(target=time.sleep,args=(0.1,)); t.start(); t.join()'

That produces both PID and TGID exit notifications for the same
process.  The PID exit record reports a valid taskstats version, while
the TGID exit record reports `version 0`.


This patch (of 2):

Set stats->version = TASKSTATS_VERSION after copying the cached TGID
aggregate into the outgoing netlink payload so all taskstats records are
self-describing again.

Link: https://lkml.kernel.org/r/ba83d934e59edd431b693607de573eb9ca059309.1774810498.git.cyyzero16@gmail.com
Fixes: ad4ecbcba7 ("[PATCH] delay accounting taskstats interface send tgid once")
Signed-off-by: Yiyang Chen <cyyzero16@gmail.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de>
Cc: Fan Yu <fan.yu9@zte.com.cn>
Cc: Wang Yaxin <wang.yaxin@zte.com.cn>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-15 02:15:02 -07:00
Linus Torvalds
5c0f43e853 kernel-7.1-rc1.misc
Please consider pulling these changes from the signed kernel-7.1-rc1.misc tag.
 
 Thanks!
 Christian
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Merge tag 'kernel-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull pid_namespace updates from Christian Brauner:

 - pid_namespace: make init creation more flexible

   Annotate ->child_reaper accesses with {READ,WRITE}_ONCE() to protect
   the unlocked readers from cpu/compiler reordering, and enforce that
   pid 1 in a pid namespace is always the first allocated pid (the
   set_tid path already required this).

   On top of that, allow opening pid_for_children before the pid
   namespace init has been created. This lets one process create the pid
   namespace and a different process create the init via setns(), which
   makes clone3(set_tid) usable in all cases evenly and is particularly
   useful to CRIU when restoring nested containers.

   A new selftest covers both the basic create-pidns-then-init flow and
   the cross-process variant, and a MAINTAINERS entry for the pid
   namespace code is added.

 - unrelated signal cleanup: update outdated comment for the removed
   freezable_schedule()

* tag 'kernel-7.1-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  signal: update outdated comment for removed freezable_schedule()
  MAINTAINERS: add a pid namespace entry
  selftests: Add tests for creating pidns init via setns
  pid_namespace: allow opening pid_for_children before init was created
  pid: check init is created first after idr alloc
  pid_namespace: avoid optimization of accesses to ->child_reaper
2026-04-14 20:28:40 -07:00
Linus Torvalds
7c8a4671dc vfs-7.1-rc1.mount.v2
Please consider pulling these changes from the signed vfs-7.1-rc1.mount.v2 tag.
 
 Thanks!
 Christian
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Merge tag 'vfs-7.1-rc1.mount.v2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs mount updates from Christian Brauner:

 - Add FSMOUNT_NAMESPACE flag to fsmount() that creates a new mount
   namespace with the newly created filesystem attached to a copy of the
   real rootfs. This returns a namespace file descriptor instead of an
   O_PATH mount fd, similar to how OPEN_TREE_NAMESPACE works for
   open_tree().

   This allows creating a new filesystem and immediately placing it in a
   new mount namespace in a single operation, which is useful for
   container runtimes and other namespace-based isolation mechanisms.

   This accompanies OPEN_TREE_NAMESPACE and avoids a needless detour via
   OPEN_TREE_NAMESPACE to get the same effect. Will be especially useful
   when you mount an actual filesystem to be used as the container
   rootfs.

 - Currently, creating a new mount namespace always copies the entire
   mount tree from the caller's namespace. For containers and sandboxes
   that intend to build their mount table from scratch this is wasteful:
   they inherit a potentially large mount tree only to immediately tear
   it down.

   This series adds support for creating a mount namespace that contains
   only a clone of the root mount, with none of the child mounts. Two
   new flags are introduced:

     - CLONE_EMPTY_MNTNS (0x400000000) for clone3(), using the 64-bit flag space
     - UNSHARE_EMPTY_MNTNS (0x00100000) for unshare()

   Both flags imply CLONE_NEWNS. The resulting namespace contains a
   single nullfs root mount with an immutable empty directory. The
   intended workflow is to then mount a real filesystem (e.g., tmpfs)
   over the root and build the mount table from there.

 - Allow MOVE_MOUNT_BENEATH to target the caller's rootfs, allowing to
   switch out the rootfs without pivot_root(2).

   The traditional approach to switching the rootfs involves
   pivot_root(2) or a chroot_fs_refs()-based mechanism that atomically
   updates fs->root for all tasks sharing the same fs_struct. This has
   consequences for fork(), unshare(CLONE_FS), and setns().

   This series instead decomposes root-switching into individually
   atomic, locally-scoped steps:

	fd_tree = open_tree(-EBADF, "/newroot", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
	fchdir(fd_tree);
	move_mount(fd_tree, "", AT_FDCWD, "/", MOVE_MOUNT_BENEATH | MOVE_MOUNT_F_EMPTY_PATH);
	chroot(".");
	umount2(".", MNT_DETACH);

   Since each step only modifies the caller's own state, the
   fork/unshare/setns races are eliminated by design.

   A key step to making this possible is to remove the locked mount
   restriction. Originally MOVE_MOUNT_BENEATH doesn't support mounting
   beneath a mount that is locked. The locked mount protects the
   underlying mount from being revealed. This is a core mechanism of
   unshare(CLONE_NEWUSER | CLONE_NEWNS). The mounts in the new mount
   namespace become locked. That effectively makes the new mount table
   useless as the caller cannot ever get rid of any of the mounts no
   matter how useless they are.

   We can lift this restriction though. We simply transfer the locked
   property from the top mount to the mount beneath. This works because
   what we care about is to protect the underlying mount aka the parent.
   The mount mounted between the parent and the top mount takes over the
   job of protecting the parent mount from the top mount mount. This
   leaves us free to remove the locked property from the top mount which
   can consequently be unmounted:

	unshare(CLONE_NEWUSER | CLONE_NEWNS)

   and we inherit a clone of procfs on /proc then currently we cannot
   unmount it as:

	umount -l /proc

   will fail with EINVAL because the procfs mount is locked.

   After this series we can now do:

	mount --beneath -t tmpfs tmpfs /proc
	umount -l /proc

   after which a tmpfs mount has been placed beneath the procfs mount.
   The tmpfs mount has become locked and the procfs mount has become
   unlocked.

   This means you can safely modify an inherited mount table after
   unprivileged namespace creation.

   Afterwards we simply make it possible to move a mount beneath the
   rootfs allowing to upgrade the rootfs.

   Removing the locked restriction makes this very useful for containers
   created with unshare(CLONE_NEWUSER | CLONE_NEWNS) to reshuffle an
   inherited mount table safely and MOVE_MOUNT_BENEATH makes it possible
   to switch out the rootfs instead of using the costly pivot_root(2).

* tag 'vfs-7.1-rc1.mount.v2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  selftests/namespaces: remove unused utils.h include from listns_efault_test
  selftests/fsmount_ns: add missing TARGETS and fix cap test
  selftests/empty_mntns: fix wrong CLONE_EMPTY_MNTNS hex value in comment
  selftests/empty_mntns: fix statmount_alloc() signature mismatch
  selftests/statmount: remove duplicate wait_for_pid()
  mount: always duplicate mount
  selftests/filesystems: add MOVE_MOUNT_BENEATH rootfs tests
  move_mount: allow MOVE_MOUNT_BENEATH on the rootfs
  move_mount: transfer MNT_LOCKED
  selftests/filesystems: add clone3 tests for empty mount namespaces
  selftests/filesystems: add tests for empty mount namespaces
  namespace: allow creating empty mount namespaces
  selftests: add FSMOUNT_NAMESPACE tests
  selftests/statmount: add statmount_alloc() helper
  tools: update mount.h header
  mount: add FSMOUNT_NAMESPACE
  mount: simplify __do_loopback()
  mount: start iterating from start of rbtree
2026-04-14 19:59:25 -07:00
Linus Torvalds
f5ad410100 bpf-next-7.1
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Merge tag 'bpf-next-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Pull bpf updates from Alexei Starovoitov:

 - Welcome new BPF maintainers: Kumar Kartikeya Dwivedi, Eduard
   Zingerman while Martin KaFai Lau reduced his load to Reviwer.

 - Lots of fixes everywhere from many first time contributors. Thank you
   All.

 - Diff stat is dominated by mechanical split of verifier.c into
   multiple components:

    - backtrack.c: backtracking logic and jump history
    - states.c:    state equivalence
    - cfg.c:       control flow graph, postorder, strongly connected
                   components
    - liveness.c:  register and stack liveness
    - fixups.c:    post-verification passes: instruction patching, dead
                   code removal, bpf_loop inlining, finalize fastcall

   8k line were moved. verifier.c still stands at 20k lines.

   Further refactoring is planned for the next release.

 - Replace dynamic stack liveness with static stack liveness based on
   data flow analysis.

   This improved the verification time by 2x for some programs and
   equally reduced memory consumption. New logic is in liveness.c and
   supported by constant folding in const_fold.c (Eduard Zingerman,
   Alexei Starovoitov)

 - Introduce BTF layout to ease addition of new BTF kinds (Alan Maguire)

 - Use kmalloc_nolock() universally in BPF local storage (Amery Hung)

 - Fix several bugs in linked registers delta tracking (Daniel Borkmann)

 - Improve verifier support of arena pointers (Emil Tsalapatis)

 - Improve verifier tracking of register bounds in min/max and tnum
   domains (Harishankar Vishwanathan, Paul Chaignon, Hao Sun)

 - Further extend support for implicit arguments in the verifier (Ihor
   Solodrai)

 - Add support for nop,nop5 instruction combo for USDT probes in libbpf
   (Jiri Olsa)

 - Support merging multiple module BTFs (Josef Bacik)

 - Extend applicability of bpf_kptr_xchg (Kaitao Cheng)

 - Retire rcu_trace_implies_rcu_gp() (Kumar Kartikeya Dwivedi)

 - Support variable offset context access for 'syscall' programs (Kumar
   Kartikeya Dwivedi)

 - Migrate bpf_task_work and dynptr to kmalloc_nolock() (Mykyta
   Yatsenko)

 - Fix UAF in in open-coded task_vma iterator (Puranjay Mohan)

* tag 'bpf-next-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (241 commits)
  selftests/bpf: cover short IPv4/IPv6 inputs with adjust_room
  bpf: reject short IPv4/IPv6 inputs in bpf_prog_test_run_skb
  selftests/bpf: Use memfd_create instead of shm_open in cgroup_iter_memcg
  selftests/bpf: Add test for cgroup storage OOB read
  bpf: Fix OOB in pcpu_init_value
  selftests/bpf: Fix reg_bounds to match new tnum-based refinement
  selftests/bpf: Add tests for non-arena/arena operations
  bpf: Allow instructions with arena source and non-arena dest registers
  bpftool: add missing fsession to the usage and docs of bpftool
  docs/bpf: add missing fsession attach type to docs
  bpf: add missing fsession to the verifier log
  bpf: Move BTF checking logic into check_btf.c
  bpf: Move backtracking logic to backtrack.c
  bpf: Move state equivalence logic to states.c
  bpf: Move check_cfg() into cfg.c
  bpf: Move compute_insn_live_regs() into liveness.c
  bpf: Move fixup/post-processing logic from verifier.c into fixups.c
  bpf: Simplify do_check_insn()
  bpf: Move checks for reserved fields out of the main pass
  bpf: Delete unused variable
  ...
2026-04-14 18:04:04 -07:00
Linus Torvalds
88b29f3f57 Modules changes for v7.1-rc1
Kernel symbol flags:
 
   - Replace the separate *_gpl symbol sections (__ksymtab_gpl and
     __kcrctab_gpl) with a unified symbol table and a new
     __kflagstab section. This section stores symbol flags, such as
     the GPL-only flag, as an 8-bit bitset for each exported symbol.
     This is a cleanup that simplifies symbol lookup in the module
     loader by avoiding table fragmentation and will allow a cleaner
     way to add more flags later if needed.
 
 Module signature UAPI:
 
   - Move struct module_signature to the UAPI headers to allow reuse
     by tools outside the kernel proper, such as kmod and
     scripts/sign-file. This also renames a few constants for clarity
     and drops unused signature types as preparation for hash-based
     module integrity checking work that's in progress.
 
 Sysfs:
 
   - Add a /sys/module/<module>/import_ns sysfs attribute to show
     the symbol namespaces imported by loaded modules. This makes it
     easier to verify driver API access at runtime on systems that
     care about such things (e.g. Android).
 
 Cleanups and fixes:
 
   - Force sh_addr to 0 for all sections in module.lds. This prevents
     non-zero section addresses when linking modules with ld.bfd -r,
     which confused elfutils.
 
   - Fix a memory leak of charp module parameters on module unload
     when the kernel is configured with CONFIG_SYSFS=n.
 
   - Override the -EEXIST error code returned by module_init() to
     userspace. This prevents confusion with the errno reserved by
     the module loader to indicate that a module is already loaded.
 
   - Simplify the warning message and drop the stack dump on positive
     returns from module_init().
 
   - Drop unnecessary extern keywords from function declarations and
     synchronize parse_args() arguments with their implementation.
 
 Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
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Merge tag 'modules-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux

Pull module updates from Sami Tolvanen:
 "Kernel symbol flags:

   - Replace the separate *_gpl symbol sections (__ksymtab_gpl and
     __kcrctab_gpl) with a unified symbol table and a new __kflagstab
     section.

     This section stores symbol flags, such as the GPL-only flag, as an
     8-bit bitset for each exported symbol. This is a cleanup that
     simplifies symbol lookup in the module loader by avoiding table
     fragmentation and will allow a cleaner way to add more flags later
     if needed.

  Module signature UAPI:

   - Move struct module_signature to the UAPI headers to allow reuse by
     tools outside the kernel proper, such as kmod and
     scripts/sign-file.

     This also renames a few constants for clarity and drops unused
     signature types as preparation for hash-based module integrity
     checking work that's in progress.

  Sysfs:

   - Add a /sys/module/<module>/import_ns sysfs attribute to show the
     symbol namespaces imported by loaded modules.

     This makes it easier to verify driver API access at runtime on
     systems that care about such things (e.g. Android).

  Cleanups and fixes:

   - Force sh_addr to 0 for all sections in module.lds. This prevents
     non-zero section addresses when linking modules with 'ld.bfd -r',
     which confused elfutils.

   - Fix a memory leak of charp module parameters on module unload when
     the kernel is configured with CONFIG_SYSFS=n.

   - Override the -EEXIST error code returned by module_init() to
     userspace. This prevents confusion with the errno reserved by the
     module loader to indicate that a module is already loaded.

   - Simplify the warning message and drop the stack dump on positive
     returns from module_init().

   - Drop unnecessary extern keywords from function declarations and
     synchronize parse_args() arguments with their implementation"

* tag 'modules-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux: (23 commits)
  module: Simplify warning on positive returns from module_init()
  module: Override -EEXIST module return
  documentation: remove references to *_gpl sections
  module: remove *_gpl sections from vmlinux and modules
  module: deprecate usage of *_gpl sections in module loader
  module: use kflagstab instead of *_gpl sections
  module: populate kflagstab in modpost
  module: add kflagstab section to vmlinux and modules
  module: define ksym_flags enumeration to represent kernel symbol flags
  selftests/bpf: verify_pkcs7_sig: Use 'struct module_signature' from the UAPI headers
  sign-file: use 'struct module_signature' from the UAPI headers
  tools uapi headers: add linux/module_signature.h
  module: Move 'struct module_signature' to UAPI
  module: Give MODULE_SIG_STRING a more descriptive name
  module: Give 'enum pkey_id_type' a more specific name
  module: Drop unused signature types
  extract-cert: drop unused definition of PKEY_ID_PKCS7
  docs: symbol-namespaces: mention sysfs attribute
  module: expose imported namespaces via sysfs
  module: Remove extern keyword from param prototypes
  ...
2026-04-14 17:16:38 -07:00
Linus Torvalds
c43267e679 arm64 updates for 7.1:
Core features:
 
  - Add support for FEAT_LSUI, allowing futex atomic operations without
    toggling Privileged Access Never (PAN)
 
  - Further refactor the arm64 exception handling code towards the
    generic entry infrastructure
 
  - Optimise __READ_ONCE() with CONFIG_LTO=y and allow alias analysis
    through it
 
 Memory management:
 
  - Refactor the arm64 TLB invalidation API and implementation for better
    control over barrier placement and level-hinted invalidation
 
  - Enable batched TLB flushes during memory hot-unplug
 
  - Fix rodata=full block mapping support for realm guests (when
    BBML2_NOABORT is available)
 
 Perf and PMU:
 
  - Add support for a whole bunch of system PMUs featured in NVIDIA's
    Tegra410 SoC (cspmu extensions for the fabric and PCIe, new drivers
    for CPU/C2C memory latency PMUs)
 
  - Clean up iomem resource handling in the Arm CMN driver
 
  - Fix signedness handling of AA64DFR0.{PMUVer,PerfMon}
 
 MPAM (Memory Partitioning And Monitoring):
 
  - Add architecture context-switch and hiding of the feature from KVM
 
  - Add interface to allow MPAM to be exposed to user-space using resctrl
 
  - Add errata workaround for some existing platforms
 
  - Add documentation for using MPAM and what shape of platforms can use
    resctrl
 
 Miscellaneous:
 
  - Check DAIF (and PMR, where relevant) at task-switch time
 
  - Skip TFSR_EL1 checks and barriers in synchronous MTE tag check mode
    (only relevant to asynchronous or asymmetric tag check modes)
 
  - Remove a duplicate allocation in the kexec code
 
  - Remove redundant save/restore of SCS SP on entry to/from EL0
 
  - Generate the KERNEL_HWCAP_ definitions from the arm64 hwcap
    descriptions
 
  - Add kselftest coverage for cmpbr_sigill()
 
  - Update sysreg definitions
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 "The biggest changes are MPAM enablement in drivers/resctrl and new PMU
  support under drivers/perf.

  On the core side, FEAT_LSUI lets futex atomic operations with EL0
  permissions, avoiding PAN toggling.

  The rest is mostly TLB invalidation refactoring, further generic entry
  work, sysreg updates and a few fixes.

  Core features:

   - Add support for FEAT_LSUI, allowing futex atomic operations without
     toggling Privileged Access Never (PAN)

   - Further refactor the arm64 exception handling code towards the
     generic entry infrastructure

   - Optimise __READ_ONCE() with CONFIG_LTO=y and allow alias analysis
     through it

  Memory management:

   - Refactor the arm64 TLB invalidation API and implementation for
     better control over barrier placement and level-hinted invalidation

   - Enable batched TLB flushes during memory hot-unplug

   - Fix rodata=full block mapping support for realm guests (when
     BBML2_NOABORT is available)

  Perf and PMU:

   - Add support for a whole bunch of system PMUs featured in NVIDIA's
     Tegra410 SoC (cspmu extensions for the fabric and PCIe, new drivers
     for CPU/C2C memory latency PMUs)

   - Clean up iomem resource handling in the Arm CMN driver

   - Fix signedness handling of AA64DFR0.{PMUVer,PerfMon}

  MPAM (Memory Partitioning And Monitoring):

   - Add architecture context-switch and hiding of the feature from KVM

   - Add interface to allow MPAM to be exposed to user-space using
     resctrl

   - Add errata workaround for some existing platforms

   - Add documentation for using MPAM and what shape of platforms can
     use resctrl

  Miscellaneous:

   - Check DAIF (and PMR, where relevant) at task-switch time

   - Skip TFSR_EL1 checks and barriers in synchronous MTE tag check mode
     (only relevant to asynchronous or asymmetric tag check modes)

   - Remove a duplicate allocation in the kexec code

   - Remove redundant save/restore of SCS SP on entry to/from EL0

   - Generate the KERNEL_HWCAP_ definitions from the arm64 hwcap
     descriptions

   - Add kselftest coverage for cmpbr_sigill()

   - Update sysreg definitions"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (109 commits)
  arm64: rsi: use linear-map alias for realm config buffer
  arm64: Kconfig: fix duplicate word in CMDLINE help text
  arm64: mte: Skip TFSR_EL1 checks and barriers in synchronous tag check mode
  arm64/sysreg: Update ID_AA64SMFR0_EL1 description to DDI0601 2025-12
  arm64/sysreg: Update ID_AA64ZFR0_EL1 description to DDI0601 2025-12
  arm64/sysreg: Update ID_AA64FPFR0_EL1 description to DDI0601 2025-12
  arm64/sysreg: Update ID_AA64ISAR2_EL1 description to DDI0601 2025-12
  arm64/sysreg: Update ID_AA64ISAR0_EL1 description to DDI0601 2025-12
  arm64/hwcap: Generate the KERNEL_HWCAP_ definitions for the hwcaps
  arm64: kexec: Remove duplicate allocation for trans_pgd
  ACPI: AGDI: fix missing newline in error message
  arm64: Check DAIF (and PMR) at task-switch time
  arm64: entry: Use split preemption logic
  arm64: entry: Use irqentry_{enter_from,exit_to}_kernel_mode()
  arm64: entry: Consistently prefix arm64-specific wrappers
  arm64: entry: Don't preempt with SError or Debug masked
  entry: Split preemption from irqentry_exit_to_kernel_mode()
  entry: Split kernel mode logic from irqentry_{enter,exit}()
  entry: Move irqentry_enter() prototype later
  entry: Remove local_irq_{enable,disable}_exit_to_user()
  ...
2026-04-14 16:48:56 -07:00
Linus Torvalds
1c3b68f0d5 Scheduler changes for v7.1:
Fair scheduling updates:
 
  - Skip SCHED_IDLE rq for SCHED_IDLE tasks (Christian Loehle)
  - Remove superfluous rcu_read_lock() in the wakeup path (K Prateek Nayak)
  - Simplify the entry condition for update_idle_cpu_scan() (K Prateek Nayak)
  - Simplify SIS_UTIL handling in select_idle_cpu() (K Prateek Nayak)
  - Avoid overflow in enqueue_entity() (K Prateek Nayak)
  - Update overutilized detection (Vincent Guittot)
  - Prevent negative lag increase during delayed dequeue (Vincent Guittot)
  - Clear buddies for preempt_short (Vincent Guittot)
  - Implement more complex proportional newidle balance (Peter Zijlstra)
  - Increase weight bits for avg_vruntime (Peter Zijlstra)
  - Use full weight to __calc_delta() (Peter Zijlstra)
 
 RT and DL scheduling updates:
 
  - Fix incorrect schedstats for rt and dl thread (Dengjun Su)
  - Skip group schedulable check with rt_group_sched=0 (Michal Koutný)
  - Move group schedulability check to sched_rt_global_validate()
    (Michal Koutný)
  - Add reporting of runtime left & abs deadline to sched_getattr()
    for DEADLINE tasks (Tommaso Cucinotta)
 
 Scheduling topology updates by K Prateek Nayak:
 
  - Compute sd_weight considering cpuset partitions
  - Extract "imb_numa_nr" calculation into a separate helper
  - Allocate per-CPU sched_domain_shared in s_data
  - Switch to assigning "sd->shared" from s_data
  - Remove sched_domain_shared allocation with sd_data
 
 Energy-aware scheduling updates:
 
  - Filter false overloaded_group case for EAS (Vincent Guittot)
  - PM: EM: Switch to rcu_dereference_all() in wakeup path
    (Dietmar Eggemann)
 
 Infrastructure updates:
 
  - Replace use of system_unbound_wq with system_dfl_wq (Marco Crivellari)
 
 Proxy scheduling updates by John Stultz:
 
  - Make class_schedulers avoid pushing current, and get rid of proxy_tag_curr()
  - Minimise repeated sched_proxy_exec() checking
  - Fix potentially missing balancing with Proxy Exec
  - Fix and improve task::blocked_on et al handling
  - Add assert_balance_callbacks_empty() helper
  - Add logic to zap balancing callbacks if we pick again
  - Move attach_one_task() and attach_task() helpers to sched.h
  - Handle blocked-waiter migration (and return migration)
  - Add K Prateek Nayak to scheduler reviewers for proxy execution
 
 Misc cleanups and fixes by John Stultz, Joseph Salisbury,
 Peter Zijlstra, K Prateek Nayak, Michal Koutný, Randy Dunlap,
 Shrikanth Hegde, Vincent Guittot, Zhan Xusheng, Xie Yuanbin
 and Vincent Guittot.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
 "Fair scheduling updates:
   - Skip SCHED_IDLE rq for SCHED_IDLE tasks (Christian Loehle)
   - Remove superfluous rcu_read_lock() in the wakeup path (K Prateek Nayak)
   - Simplify the entry condition for update_idle_cpu_scan() (K Prateek Nayak)
   - Simplify SIS_UTIL handling in select_idle_cpu() (K Prateek Nayak)
   - Avoid overflow in enqueue_entity() (K Prateek Nayak)
   - Update overutilized detection (Vincent Guittot)
   - Prevent negative lag increase during delayed dequeue (Vincent Guittot)
   - Clear buddies for preempt_short (Vincent Guittot)
   - Implement more complex proportional newidle balance (Peter Zijlstra)
   - Increase weight bits for avg_vruntime (Peter Zijlstra)
   - Use full weight to __calc_delta() (Peter Zijlstra)

  RT and DL scheduling updates:
   - Fix incorrect schedstats for rt and dl thread (Dengjun Su)
   - Skip group schedulable check with rt_group_sched=0 (Michal Koutný)
   - Move group schedulability check to sched_rt_global_validate()
     (Michal Koutný)
   - Add reporting of runtime left & abs deadline to sched_getattr()
     for DEADLINE tasks (Tommaso Cucinotta)

  Scheduling topology updates by K Prateek Nayak:
   - Compute sd_weight considering cpuset partitions
   - Extract "imb_numa_nr" calculation into a separate helper
   - Allocate per-CPU sched_domain_shared in s_data
   - Switch to assigning "sd->shared" from s_data
   - Remove sched_domain_shared allocation with sd_data

  Energy-aware scheduling updates:
   - Filter false overloaded_group case for EAS (Vincent Guittot)
   - PM: EM: Switch to rcu_dereference_all() in wakeup path
     (Dietmar Eggemann)

  Infrastructure updates:
   - Replace use of system_unbound_wq with system_dfl_wq (Marco Crivellari)

  Proxy scheduling updates by John Stultz:
   - Make class_schedulers avoid pushing current, and get rid of proxy_tag_curr()
   - Minimise repeated sched_proxy_exec() checking
   - Fix potentially missing balancing with Proxy Exec
   - Fix and improve task::blocked_on et al handling
   - Add assert_balance_callbacks_empty() helper
   - Add logic to zap balancing callbacks if we pick again
   - Move attach_one_task() and attach_task() helpers to sched.h
   - Handle blocked-waiter migration (and return migration)
   - Add K Prateek Nayak to scheduler reviewers for proxy execution

  Misc cleanups and fixes by John Stultz, Joseph Salisbury, Peter
  Zijlstra, K Prateek Nayak, Michal Koutný, Randy Dunlap, Shrikanth
  Hegde, Vincent Guittot, Zhan Xusheng, Xie Yuanbin and Vincent Guittot"

* tag 'sched-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
  sched/eevdf: Clear buddies for preempt_short
  sched/rt: Cleanup global RT bandwidth functions
  sched/rt: Move group schedulability check to sched_rt_global_validate()
  sched/rt: Skip group schedulable check with rt_group_sched=0
  sched/fair: Avoid overflow in enqueue_entity()
  sched: Use u64 for bandwidth ratio calculations
  sched/fair: Prevent negative lag increase during delayed dequeue
  sched/fair: Use sched_energy_enabled()
  sched: Handle blocked-waiter migration (and return migration)
  sched: Move attach_one_task and attach_task helpers to sched.h
  sched: Add logic to zap balance callbacks if we pick again
  sched: Add assert_balance_callbacks_empty helper
  sched/locking: Add special p->blocked_on==PROXY_WAKING value for proxy return-migration
  sched: Fix modifying donor->blocked on without proper locking
  locking: Add task::blocked_lock to serialize blocked_on state
  sched: Fix potentially missing balancing with Proxy Exec
  sched: Minimise repeated sched_proxy_exec() checking
  sched: Make class_schedulers avoid pushing current, and get rid of proxy_tag_curr()
  MAINTAINERS: Add K Prateek Nayak to scheduler reviewers
  sched/core: Get this cpu once in ttwu_queue_cond()
  ...
2026-04-14 13:33:36 -07:00
Linus Torvalds
33c66eb5e9 Performance events changes for v7.1:
Core updates:
 
  - Try to allocate task_ctx_data quickly, to optimize
    O(N^2) algorithm on large systems with O(100k) threads
    (Namhyung Kim)
 
 AMD PMU driver IBS support updates and fixes, by Ravi Bangoria:
 
  - Fix interrupt accounting for discarded samples
  - Fix a Zen5-specific quirk
  - Fix PhyAddrVal handling
  - Fix NMI-safety with perf_allow_kernel()
  - Fix a race between event add and NMIs
 
 Intel PMU driver updates:
 
  - Only check GP counters for PEBS constraints validation (Dapeng Mi)
 
 MSR driver:
 
  - Turn SMI_COUNT and PPERF on by default, instead of a long
    list of CPU models to enable them on (Kan Liang)
 
 Misc cleanups and fixes by Aldf Conte, Anshuman Khandual, Namhyung Kim,
 Ravi Bangoria and Yen-Hsiang Hsu.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull performance events updates from Ingo Molnar:
 "Core updates:

   - Try to allocate task_ctx_data quickly, to optimize O(N^2) algorithm
     on large systems with O(100k) threads (Namhyung Kim)

  AMD PMU driver IBS support updates and fixes, by Ravi Bangoria:
   - Fix interrupt accounting for discarded samples
   - Fix a Zen5-specific quirk
   - Fix PhyAddrVal handling
   - Fix NMI-safety with perf_allow_kernel()
   - Fix a race between event add and NMIs

  Intel PMU driver updates:
   - Only check GP counters for PEBS constraints validation (Dapeng Mi)

  MSR driver:
   - Turn SMI_COUNT and PPERF on by default, instead of a long list of
     CPU models to enable them on (Kan Liang)

  ... and misc cleanups and fixes by Aldf Conte, Anshuman Khandual,
  Namhyung Kim, Ravi Bangoria and Yen-Hsiang Hsu"

* tag 'perf-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/events: Replace READ_ONCE() with standard pgtable accessors
  perf/x86/msr: Make SMI and PPERF on by default
  perf/x86/intel/p4: Fix unused variable warning in p4_pmu_init()
  perf/x86/intel: Only check GP counters for PEBS constraints validation
  perf/x86/amd/ibs: Fix comment typo in ibs_op_data
  perf/amd/ibs: Advertise remote socket capability
  perf/amd/ibs: Enable streaming store filter
  perf/amd/ibs: Enable RIP bit63 hardware filtering
  perf/amd/ibs: Enable fetch latency filtering
  perf/amd/ibs: Support IBS_{FETCH|OP}_CTL2[Dis] to eliminate RMW race
  perf/amd/ibs: Add new MSRs and CPUID bits definitions
  perf/amd/ibs: Define macro for ldlat mask and shift
  perf/amd/ibs: Avoid race between event add and NMI
  perf/amd/ibs: Avoid calling perf_allow_kernel() from the IBS NMI handler
  perf/amd/ibs: Preserve PhyAddrVal bit when clearing PhyAddr MSR
  perf/amd/ibs: Limit ldlat->l3missonly dependency to Zen5
  perf/amd/ibs: Account interrupt for discarded samples
  perf/core: Simplify __detach_global_ctx_data()
  perf/core: Try to allocate task_ctx_data quickly
  perf/core: Pass GFP flags to attach_task_ctx_data()
2026-04-14 13:22:40 -07:00
Linus Torvalds
7393febcb1 Locking updates for v7.1:
Mutexes:
 
  - Add killable flavor to guard definitions (Davidlohr Bueso)
  - Remove the list_head from struct mutex (Matthew Wilcox)
  - Rename mutex_init_lockep() (Davidlohr Bueso)
 
 rwsems:
 
  - Remove the list_head from struct rw_semaphore and
    replace it with a single pointer (Matthew Wilcox)
  - Fix logic error in rwsem_del_waiter() (Andrei Vagin)
 
 Semaphores:
 
  - Remove the list_head from struct semaphore (Matthew Wilcox)
 
 Jump labels:
 
  - Use ATOMIC_INIT() for initialization of .enabled (Thomas Weißschuh)
  - Remove workaround for old compilers in initializations
    (Thomas Weißschuh)
 
 Lock context analysis changes and improvements:
 
  - Add context analysis for rwsems (Peter Zijlstra)
  - Fix rwlock and spinlock lock context annotations (Bart Van Assche)
  - Fix rwlock support in <linux/spinlock_up.h> (Bart Van Assche)
  - Add lock context annotations in the spinlock implementation
    (Bart Van Assche)
  - signal: Fix the lock_task_sighand() annotation (Bart Van Assche)
  - ww-mutex: Fix the ww_acquire_ctx function annotations
    (Bart Van Assche)
  - Add lock context support in do_raw_{read,write}_trylock()
    (Bart Van Assche)
  - arm64, compiler-context-analysis: Permit alias analysis through
    __READ_ONCE() with CONFIG_LTO=y (Marco Elver)
  - Add __cond_releases() (Peter Zijlstra)
  - Add context analysis for mutexes (Peter Zijlstra)
  - Add context analysis for rtmutexes (Peter Zijlstra)
  - Convert futexes to compiler context analysis (Peter Zijlstra)
 
 Rust integration updates:
 
  - Add atomic fetch_sub() implementation (Andreas Hindborg)
  - Refactor various rust_helper_ methods for expansion (Boqun Feng)
  - Add Atomic<*{mut,const} T> support (Boqun Feng)
  - Add atomic operation helpers over raw pointers (Boqun Feng)
  - Add performance-optimal Flag type for atomic booleans, to avoid
    slow byte-sized RMWs on architectures that don't support them.
    (FUJITA Tomonori)
  - Misc cleanups and fixes (Andreas Hindborg, Boqun Feng,
    FUJITA Tomonori)
 
 LTO support updates:
 
  - arm64: Optimize __READ_ONCE() with CONFIG_LTO=y (Marco Elver)
  - compiler: Simplify generic RELOC_HIDE() (Marco Elver)
 
 Miscellaneous fixes and cleanups by Peter Zijlstra, Randy Dunlap,
 Thomas Weißschuh, Davidlohr Bueso and Mikhail Gavrilov.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
 "Mutexes:

   - Add killable flavor to guard definitions (Davidlohr Bueso)

   - Remove the list_head from struct mutex (Matthew Wilcox)

   - Rename mutex_init_lockep() (Davidlohr Bueso)

  rwsems:

   - Remove the list_head from struct rw_semaphore and
     replace it with a single pointer (Matthew Wilcox)

   - Fix logic error in rwsem_del_waiter() (Andrei Vagin)

  Semaphores:

   - Remove the list_head from struct semaphore (Matthew Wilcox)

  Jump labels:

   - Use ATOMIC_INIT() for initialization of .enabled (Thomas Weißschuh)

   - Remove workaround for old compilers in initializations
     (Thomas Weißschuh)

  Lock context analysis changes and improvements:

   - Add context analysis for rwsems (Peter Zijlstra)

   - Fix rwlock and spinlock lock context annotations (Bart Van Assche)

   - Fix rwlock support in <linux/spinlock_up.h> (Bart Van Assche)

   - Add lock context annotations in the spinlock implementation
     (Bart Van Assche)

   - signal: Fix the lock_task_sighand() annotation (Bart Van Assche)

   - ww-mutex: Fix the ww_acquire_ctx function annotations
     (Bart Van Assche)

   - Add lock context support in do_raw_{read,write}_trylock()
     (Bart Van Assche)

   - arm64, compiler-context-analysis: Permit alias analysis through
     __READ_ONCE() with CONFIG_LTO=y (Marco Elver)

   - Add __cond_releases() (Peter Zijlstra)

   - Add context analysis for mutexes (Peter Zijlstra)

   - Add context analysis for rtmutexes (Peter Zijlstra)

   - Convert futexes to compiler context analysis (Peter Zijlstra)

  Rust integration updates:

   - Add atomic fetch_sub() implementation (Andreas Hindborg)

   - Refactor various rust_helper_ methods for expansion (Boqun Feng)

   - Add Atomic<*{mut,const} T> support (Boqun Feng)

   - Add atomic operation helpers over raw pointers (Boqun Feng)

   - Add performance-optimal Flag type for atomic booleans, to avoid
     slow byte-sized RMWs on architectures that don't support them.
     (FUJITA Tomonori)

   - Misc cleanups and fixes (Andreas Hindborg, Boqun Feng, FUJITA
     Tomonori)

  LTO support updates:

   - arm64: Optimize __READ_ONCE() with CONFIG_LTO=y (Marco Elver)

   - compiler: Simplify generic RELOC_HIDE() (Marco Elver)

  Miscellaneous fixes and cleanups by Peter Zijlstra, Randy Dunlap,
  Thomas Weißschuh, Davidlohr Bueso and Mikhail Gavrilov"

* tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
  compiler: Simplify generic RELOC_HIDE()
  locking: Add lock context annotations in the spinlock implementation
  locking: Add lock context support in do_raw_{read,write}_trylock()
  locking: Fix rwlock support in <linux/spinlock_up.h>
  lockdep: Raise default stack trace limits when KASAN is enabled
  cleanup: Optimize guards
  jump_label: remove workaround for old compilers in initializations
  jump_label: use ATOMIC_INIT() for initialization of .enabled
  futex: Convert to compiler context analysis
  locking/rwsem: Fix logic error in rwsem_del_waiter()
  locking/rwsem: Add context analysis
  locking/rtmutex: Add context analysis
  locking/mutex: Add context analysis
  compiler-context-analysys: Add __cond_releases()
  locking/mutex: Remove the list_head from struct mutex
  locking/semaphore: Remove the list_head from struct semaphore
  locking/rwsem: Remove the list_head from struct rw_semaphore
  rust: atomic: Update a safety comment in impl of `fetch_add()`
  rust: sync: atomic: Update documentation for `fetch_add()`
  rust: sync: atomic: Add fetch_sub()
  ...
2026-04-14 12:36:25 -07:00
Linus Torvalds
e80d033851 Updates for the SMP core code:
- Switch smp_call_on_cpu() to user system_percpu_wq instead of system_wq
     a part of the ongoing workqueue restructuring
 
   - Improve the CSD-lock diagnostics for smp_call_function_single() to
     provide better debug mechanisms on weakly ordered systems.
 
   - Cache the current CPU number once in smp_call_function*() instead of
     retrieving it over and over.
 
   - Add missing kernel-doc comments all over the place
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Merge tag 'smp-core-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull SMP core updates from Thomas Gleixner:

 - Switch smp_call_on_cpu() to user system_percpu_wq instead of
   system_wq a part of the ongoing workqueue restructuring

 - Improve the CSD-lock diagnostics for smp_call_function_single() to
   provide better debug mechanisms on weakly ordered systems.

 - Cache the current CPU number once in smp_call_function*() instead of
   retrieving it over and over.

 - Add missing kernel-doc comments all over the place

* tag 'smp-core-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp: Use system_percpu_wq instead of system_wq
  smp: Improve smp_call_function_single() CSD-lock diagnostics
  smp: Get this_cpu once in smp_call_function
  smp: Add missing kernel-doc comments
2026-04-14 11:14:56 -07:00
Linus Torvalds
f21f7b5162 Update to the VDSO subsystem:
- Make the handling of compat functions consistent and more robust
 
      - Rework the underlying data store so that it is dynamically
        allocated, which allows the conversion of the last holdout SPARC64
        to the generic VDSO implementation
 
      - Rework the SPARC64 VDSO to utilize the generic implementation
 
      - Mop up the left overs of the non-generic VDSO support in the core
        code.
 
      - Expand the VDSO selftest and make them more robust
 
      - Allow time namespaces to be enabled independently of the generic
        VDSO support, which was not possible before due to SPARC64 not
        using it.
 
      - Various cleanups and improvements in the related code.
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Merge tag 'timers-vdso-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull vdso updates from Thomas Gleixner:

 - Make the handling of compat functions consistent and more robust

 - Rework the underlying data store so that it is dynamically allocated,
   which allows the conversion of the last holdout SPARC64 to the
   generic VDSO implementation

 - Rework the SPARC64 VDSO to utilize the generic implementation

 - Mop up the left overs of the non-generic VDSO support in the core
   code

 - Expand the VDSO selftest and make them more robust

 - Allow time namespaces to be enabled independently of the generic VDSO
   support, which was not possible before due to SPARC64 not using it

 - Various cleanups and improvements in the related code

* tag 'timers-vdso-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  timens: Use task_lock guard in timens_get*()
  timens: Use mutex guard in proc_timens_set_offset()
  timens: Simplify some calls to put_time_ns()
  timens: Add a __free() wrapper for put_time_ns()
  timens: Remove dependency on the vDSO
  vdso/timens: Move functions to new file
  selftests: vDSO: vdso_test_correctness: Add a test for time()
  selftests: vDSO: vdso_test_correctness: Use facilities from parse_vdso.c
  selftests: vDSO: vdso_test_correctness: Handle different tv_usec types
  selftests: vDSO: vdso_test_correctness: Drop SYS_getcpu fallbacks
  selftests: vDSO: vdso_test_gettimeofday: Remove nolibc checks
  Revert "selftests: vDSO: parse_vdso: Use UAPI headers instead of libc headers"
  random: vDSO: Remove ifdeffery
  random: vDSO: Trim vDSO includes
  vdso/datapage: Trim down unnecessary includes
  vdso/datapage: Remove inclusion of gettimeofday.h
  vdso/helpers: Explicitly include vdso/processor.h
  vdso/gettimeofday: Add explicit includes
  random: vDSO: Add explicit includes
  MIPS: vdso: Explicitly include asm/vdso/vdso.h
  ...
2026-04-14 10:53:44 -07:00
Linus Torvalds
c1fe867b5b Updates for the timer/timekeeping core:
- A rework of the hrtimer subsystem to reduce the overhead for frequently
     armed timers, especially the hrtick scheduler timer.
 
       - Better timer locality decision
 
       - Simplification of the evaluation of the first expiry time by
         keeping track of the neighbor timers in the RB-tree by providing a
         RB-tree variant with neighbor links. That avoids walking the
         RB-tree on removal to find the next expiry time, but even more
         important allows to quickly evaluate whether a timer which is
         rearmed changes the position in the RB-tree with the modified
         expiry time or not. If not, the dequeue/enqueue sequence which both
         can end up in rebalancing can be completely avoided.
 
       - Deferred reprogramming of the underlying clock event device. This
         optimizes for the situation where a hrtimer callback sets the need
         resched bit. In that case the code attempts to defer the
         re-programming of the clock event device up to the point where the
         scheduler has picked the next task and has the next hrtick timer
         armed. In case that there is no immediate reschedule or soft
         interrupts have to be handled before reaching the reschedule point
         in the interrupt entry code the clock event is reprogrammed in one
         of those code paths to prevent that the timer becomes stale.
 
       - Support for clocksource coupled clockevents
 
       	The TSC deadline timer is coupled to the TSC. The next event is
       	programmed in TSC time. Currently this is done by converting the
       	CLOCK_MONOTONIC based expiry value into a relative timeout,
       	converting it into TSC ticks, reading the TSC adding the delta
       	ticks and writing the deadline MSR.
 
 	As the timekeeping core has the conversion factors for the TSC
 	already, the whole back and forth conversion can be completely
 	avoided. The timekeeping core calculates the reverse conversion
 	factors from nanoseconds to TSC ticks and utilizes the base
 	timestamps of TSC and CLOCK_MONOTONIC which are updated once per
 	tick. This allows a direct conversion into the TSC deadline value
 	without reading the time and as a bonus keeps the deadline
 	conversion in sync with the TSC conversion factors, which are
 	updated by adjtimex() on systems with NTP/PTP enabled.
 
      - Allow inlining of the clocksource read and clockevent write
        functions when they are tiny enough, e.g. on x86 RDTSC and WRMSR.
 
     With all those enhancements in place a hrtick enabled scheduler
     provides the same performance as without hrtick. But also other hrtimer
     users obviously benefit from these optimizations.
 
   - Robustness improvements and cleanups of historical sins in the hrtimer
     and timekeeping code.
 
   - Rewrite of the clocksource watchdog.
 
     The clocksource watchdog code has over time reached the state of an
     impenetrable maze of duct tape and staples. The original design, which was
     made in the context of systems far smaller than today, is based on the
     assumption that the to be monitored clocksource (TSC) can be trivially
     compared against a known to be stable clocksource (HPET/ACPI-PM timer).
 
     Over the years this rather naive approach turned out to have major
     flaws. Long delays between the watchdog invocations can cause wrap
     arounds of the reference clocksource. The access to the reference
     clocksource degrades on large multi-sockets systems dure to
     interconnect congestion. This has been addressed with various
     heuristics which degraded the accuracy of the watchdog to the point
     that it fails to detect actual TSC problems on older hardware which
     exposes slow inter CPU drifts due to firmware manipulating the TSC to
     hide SMI time.
 
     The rewrite addresses this by:
 
       - Restricting the validation against the reference clocksource to the
         boot CPU which is usually closest to the legacy block which
         contains the reference clocksource (HPET/ACPI-PM).
 
       - Do a round robin validation betwen the boot CPU and the other CPUs
         based only on the TSC with an algorithm similar to the TSC
         synchronization code during CPU hotplug.
 
       - Being more leniant versus remote timeouts
 
   - The usual tiny fixes, cleanups and enhancements all over the place
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Merge tag 'timers-core-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer core updates from Thomas Gleixner:

 - A rework of the hrtimer subsystem to reduce the overhead for
   frequently armed timers, especially the hrtick scheduler timer:

     - Better timer locality decision

     - Simplification of the evaluation of the first expiry time by
       keeping track of the neighbor timers in the RB-tree by providing
       a RB-tree variant with neighbor links. That avoids walking the
       RB-tree on removal to find the next expiry time, but even more
       important allows to quickly evaluate whether a timer which is
       rearmed changes the position in the RB-tree with the modified
       expiry time or not. If not, the dequeue/enqueue sequence which
       both can end up in rebalancing can be completely avoided.

     - Deferred reprogramming of the underlying clock event device. This
       optimizes for the situation where a hrtimer callback sets the
       need resched bit. In that case the code attempts to defer the
       re-programming of the clock event device up to the point where
       the scheduler has picked the next task and has the next hrtick
       timer armed. In case that there is no immediate reschedule or
       soft interrupts have to be handled before reaching the reschedule
       point in the interrupt entry code the clock event is reprogrammed
       in one of those code paths to prevent that the timer becomes
       stale.

     - Support for clocksource coupled clockevents

       The TSC deadline timer is coupled to the TSC. The next event is
       programmed in TSC time. Currently this is done by converting the
       CLOCK_MONOTONIC based expiry value into a relative timeout,
       converting it into TSC ticks, reading the TSC adding the delta
       ticks and writing the deadline MSR.

       As the timekeeping core has the conversion factors for the TSC
       already, the whole back and forth conversion can be completely
       avoided. The timekeeping core calculates the reverse conversion
       factors from nanoseconds to TSC ticks and utilizes the base
       timestamps of TSC and CLOCK_MONOTONIC which are updated once per
       tick. This allows a direct conversion into the TSC deadline value
       without reading the time and as a bonus keeps the deadline
       conversion in sync with the TSC conversion factors, which are
       updated by adjtimex() on systems with NTP/PTP enabled.

     - Allow inlining of the clocksource read and clockevent write
       functions when they are tiny enough, e.g. on x86 RDTSC and WRMSR.

   With all those enhancements in place a hrtick enabled scheduler
   provides the same performance as without hrtick. But also other
   hrtimer users obviously benefit from these optimizations.

 - Robustness improvements and cleanups of historical sins in the
   hrtimer and timekeeping code.

 - Rewrite of the clocksource watchdog.

   The clocksource watchdog code has over time reached the state of an
   impenetrable maze of duct tape and staples. The original design,
   which was made in the context of systems far smaller than today, is
   based on the assumption that the to be monitored clocksource (TSC)
   can be trivially compared against a known to be stable clocksource
   (HPET/ACPI-PM timer).

   Over the years this rather naive approach turned out to have major
   flaws. Long delays between the watchdog invocations can cause wrap
   arounds of the reference clocksource. The access to the reference
   clocksource degrades on large multi-sockets systems dure to
   interconnect congestion. This has been addressed with various
   heuristics which degraded the accuracy of the watchdog to the point
   that it fails to detect actual TSC problems on older hardware which
   exposes slow inter CPU drifts due to firmware manipulating the TSC to
   hide SMI time.

   The rewrite addresses this by:

     - Restricting the validation against the reference clocksource to
       the boot CPU which is usually closest to the legacy block which
       contains the reference clocksource (HPET/ACPI-PM).

     - Do a round robin validation betwen the boot CPU and the other
       CPUs based only on the TSC with an algorithm similar to the TSC
       synchronization code during CPU hotplug.

     - Being more leniant versus remote timeouts

 - The usual tiny fixes, cleanups and enhancements all over the place

* tag 'timers-core-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
  alarmtimer: Access timerqueue node under lock in suspend
  hrtimer: Fix incorrect #endif comment for BITS_PER_LONG check
  posix-timers: Fix stale function name in comment
  timers: Get this_cpu once while clearing the idle state
  clocksource: Rewrite watchdog code completely
  clocksource: Don't use non-continuous clocksources as watchdog
  x86/tsc: Handle CLOCK_SOURCE_VALID_FOR_HRES correctly
  MIPS: Don't select CLOCKSOURCE_WATCHDOG
  parisc: Remove unused clocksource flags
  hrtimer: Add a helper to retrieve a hrtimer from its timerqueue node
  hrtimer: Remove trailing comma after HRTIMER_MAX_CLOCK_BASES
  hrtimer: Mark index and clockid of clock base as const
  hrtimer: Drop unnecessary pointer indirection in hrtimer_expire_entry event
  hrtimer: Drop spurious space in 'enum hrtimer_base_type'
  hrtimer: Don't zero-initialize ret in hrtimer_nanosleep()
  hrtimer: Remove hrtimer_get_expires_ns()
  timekeeping: Mark offsets array as const
  timekeeping/auxclock: Consistently use raw timekeeper for tk_setup_internals()
  timer_list: Print offset as signed integer
  tracing: Use explicit array size instead of sentinel elements in symbol printing
  ...
2026-04-14 10:27:07 -07:00
Linus Torvalds
db23954eea Update for the core interrupt subsystem:
- Invoke add_interrupt_randomness() in handle_percpu_devid_irq() and
      cleanup the workaround in the Hyper-V driver, which would now invoke
      it twice on ARM64. Removing it from the driver requires to add it to
      the x86 system vector entry point.
 
    - Remove the pointles cpu_read_lock() around reading CPU possible mask,
      which is read only after init.
 
    - Add documentation for the interaction between device tree bindings and
      the interrupt type defines in irq.h.
 
    - Delete stale defines in the matrix allocator and the equivalent in
      loongarch.
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Merge tag 'irq-core-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull core irq updates from Thomas Gleixner:

 - Invoke add_interrupt_randomness() in handle_percpu_devid_irq() and
   cleanup the workaround in the Hyper-V driver, which would now invoke
   it twice on ARM64. Removing it from the driver requires to add it to
   the x86 system vector entry point

 - Remove the pointles cpu_read_lock() around reading CPU possible mask,
   which is read only after init

 - Add documentation for the interaction between device tree bindings
   and the interrupt type defines in irq.h

 - Delete stale defines in the matrix allocator and the equivalent in
   loongarch

* tag 'irq-core-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Drivers: hv: Move add_interrupt_randomness() to hypervisor callback sysvec
  genirq/chip: Invoke add_interrupt_randomness() in handle_percpu_devid_irq()
  genirq/affinity: Remove cpus_read_lock() while reading cpu_possible_mask
  genirq/matrix, LoongArch: Delete IRQ_MATRIX_BITS leftovers
  genirq: Document interaction between <linux/irq.h> and DT binding defines
2026-04-14 10:02:41 -07:00
Tom Zanussi
9236eebd13 tracing: Fix fully-qualified variable reference printing in histograms
The syntax for fully-qualified variable references in histograms is
subsys.event.$var, which is parsed correctly, but not displayed correctly
when printing a histogram spec. The current code puts the $ reference at
the beginning of the fully-qualified variable name i.e. $subsys.event.var,
which is incorrect.

Before:

trigger info: hist:keys=next_comm:vals=hitcount:wakeup_lat=common_timestamp.usecs-$sched.sched_wakeup.ts0: ...

After:

trigger info: hist:keys=next_comm:vals=hitcount:wakeup_lat=common_timestamp.usecs-sched.sched_wakeup.$ts0: ...

Link: https://patch.msgid.link/5dee9a86d062a4dd68c2214f3d90ac93811e1951.1776112478.git.zanussi@kernel.org
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-04-14 05:28:10 -04:00
David Carlier
fad217e16f tracepoint: balance regfunc() on func_add() failure in tracepoint_add_func()
When a tracepoint goes through the 0 -> 1 transition, tracepoint_add_func()
invokes the subsystem's ext->regfunc() before attempting to install the
new probe via func_add(). If func_add() then fails (for example, when
allocate_probes() cannot allocate a new probe array under memory pressure
and returns -ENOMEM), the function returns the error without calling the
matching ext->unregfunc(), leaving the side effects of regfunc() behind
with no installed probe to justify them.

For syscall tracepoints this is particularly unpleasant: syscall_regfunc()
bumps sys_tracepoint_refcount and sets SYSCALL_TRACEPOINT on every task.
After a leaked failure, the refcount is stuck at a non-zero value with no
consumer, and every task continues paying the syscall trace entry/exit
overhead until reboot. Other subsystems providing regfunc()/unregfunc()
pairs exhibit similarly scoped persistent state.

Mirror the existing 1 -> 0 cleanup and call ext->unregfunc() in the
func_add() error path, gated on the same condition used there so the
unwind is symmetric with the registration.

Fixes: 8cf868affd ("tracing: Have the reg function allow to fail")
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20260413190601.21993-1-devnexen@gmail.com
Signed-off-by: David Carlier <devnexen@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-04-14 05:17:02 -04:00
Vincent Donnefort
6170922f13 ring-buffer: Prevent off-by-one array access in ring_buffer_desc_page()
As pointed out by Smatch, the ring-buffer descriptor array page_va is
counted by nr_page_va, but the accessor ring_buffer_desc_page() allows
access off by one.

Currently, this does not cause problems, as the page ID always comes
from a trusted source. Nonetheless, ensure robustness and fix the
accessor. While at it, make the page_id unsigned.

Link: https://patch.msgid.link/20260410124527.3563970-1-vdonnefort@google.com
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2026-04-14 05:13:09 -04:00