Commit Graph

1476 Commits

Author SHA1 Message Date
Vineeth Vijayan
5b76268dac s390/cio: Fix NULL pointer dereference in ccw_device_get_util_str()
The channel path registry entry associated with a CHPID may be removed
while the subchannel's PMCW still references that CHPID. In this case,
chpid_to_chp() can return NULL, leading to a NULL pointer dereference.

Add the missing NULL check before dereferencing the returned pointer.

Fixes: 199652309a ("s390/cio: add helper to query utility strings per given ccw device")
Cc: stable@vger.kernel.org
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-09-23 16:43:32 +02:00
Peter Oberparleiter
f4d04425e6 s390/cmf: Fix virtual vs physical address confusion
The measurement block address is an absolute address. Define the
associated schib_config and schib fields as dma64_t to enable automatic
detection of incorrect assignments. Also add the missing virt_to_dma64()
translation.

Without this fix, a wrong address will be used by firmware when storing
extended format channel measurement data on kernels built with
CONFIG_RANDOMIZE_IDENTITY_BASE=y.

Fixes: 14edd0d73b ("s390/cmf: fix virtual vs physical address confusion")
Cc: stable@vger.kernel.org
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-09-22 12:21:04 +02:00
Vineeth Vijayan
9590f4d838 s390/cio: Guard PMCW field accesses with dnv check
When PMCW.DNV is 0, no I/O device is associated with the subchannel.
However, several code paths access PMCW fields directly from the cached
sch->schib without first invoking the update helper. Add explicit DNV
validation before accessing PMCW fields from the cached SCHIB to avoid
using invalid data.

Reported-by: William Bezenah <wbezenah@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Fixes: 8c58a22968 ("s390/cio: Do not unregister the subchannel based on DNV")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-09-17 06:59:41 +02:00
Vineeth Vijayan
f6f2985eab s390/cio: Check pmcw.dnv before pmcw.ena in I/O entry points
The device number valid (dnv) bit in the PMCW must be checked before
acting on any other PMCW fields for IO-type subchannels. A subchannel
with dnv=0 has no valid device number associated, making it meaningless
to evaluate the enabled (ena) state or issue any I/O instruction against
it.

Reported-by: William Bezenah <wbezenah@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Fixes: 8c58a22968 ("s390/cio: Do not unregister the subchannel based on DNV")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-09-17 06:59:41 +02:00
Vineeth Vijayan
29d9e5835d s390/cio: Fix cio_update_schib() to not cache invalid schib
When pmcw.dnv is 0, the contents of all SCHIB fields are unpredictable.
Zero sch->schib in that case to prevent subsequent code from making
decisions based on unpredictable data.

Reported-by: William Bezenah <wbezenah@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Fixes: 8c58a22968 ("s390/cio: Do not unregister the subchannel based on DNV")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-09-17 06:59:41 +02:00
Linus Torvalds
66ec24c5d7 s390 updates for 7.3 merge window
- Add a cpuidle driver with polling and enabled wait states using the
   existing CPU idle infrastructure and idle governor to improve latency
   for frequent sleep/wakeup cycles. Remove the obsolete tick delay
   heuristic and generic arch_needs_cpu() hook. Add the corresponding
   driver entry to MAINTAINERS
 
 - Add kCFI support using the generic support provided by Clang
 
 - Enable Clang CONTEXT_ANALYSIS for various architecture code and for
   char, PCI, CIO and virtio drivers. Add required lock annotations,
   exclude unsupported mm helpers and remove conditional PCI locking
 
 - Fix secure storage access exception handling and reintroduce
   DCACHE_WORD_ACCESS previously removed as a workaround
 
 - Fix cpum_cf perf crashes when CPUs are brought online while per-task
   events are active. Allocate and remove per-CPU counter data from CPU
   hotplug callbacks
 
 - Fix a deadlock when an s390dbf debug area is unregistered while one
   of its debugfs files is being written to
 
 - Fix MVIY_PERCPU() with binutils older than 2.39, where an assembler
   macro silently omitted an instruction needed to repair interrupted
   operations after CPU migration
 
 - Remove/replace cond_resched() calls which are no-ops with the supported
   s390 preemption models
 
 - Fix AP queue depth and maximum message length decoding according to
   the architecture. Current hardware is not affected, but future hardware
   could report values which were handled incorrectly
 
 - Reflect the configured CPU state in cpu_enabled_mask so deconfigured
   CPUs are not presented as available for onlining
 
 - Restore the vDSO GNU_EH_FRAME program header which was lost when the
   build switched to direct linker invocation, and mark it read-only
 
 - Add SCLP action qualifiers used by Spyre for card initialization,
   recoverable error and telemetry reporting
 
 - Move KMSAN interrupt flag helpers out of line to fix
   -Wstatic-in-inline build warnings
 
 - Use level-specific page table entry accessors for hugetlb entries and
   ptep_get() when accessing crashed kernel memory in kdump
 
 - Make forced AP bus rescans killable so that a user process blocked
   behind an ongoing scan can still be terminated with SIGKILL
 
 - Rework pkey ioctl error paths to remove duplicated cleanup code and
   avoid freeing error pointers
 
 - Allow the protected guest SWIOTLB buffer to be allocated outside the
   first 2GB. Also enable dynamic SWIOTLB growth and the coherent atomic
   pool fallback to improve I/O behavior when the initial pool is exhausted
 
 - Add program check statistics and spinlock contention tracepoints.
   Increase the lockdep chain capacity to keep lockdep enabled for complex
   code paths such as btrfs
 
 - Simplify IPL, trap and syscall code and remove the obsolete unistd_32.h
   generation entry
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Merge tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add a cpuidle driver with polling and enabled wait states using the
   existing CPU idle infrastructure and idle governor to improve latency
   for frequent sleep/wakeup cycles. Remove the obsolete tick delay
   heuristic and generic arch_needs_cpu() hook. Add the corresponding
   driver entry to MAINTAINERS

 - Add kCFI support using the generic support provided by Clang

 - Enable Clang CONTEXT_ANALYSIS for various architecture code and for
   char, PCI, CIO and virtio drivers. Add required lock annotations,
   exclude unsupported mm helpers and remove conditional PCI locking

 - Fix secure storage access exception handling and reintroduce
   DCACHE_WORD_ACCESS previously removed as a workaround

 - Fix cpum_cf perf crashes when CPUs are brought online while per-task
   events are active. Allocate and remove per-CPU counter data from CPU
   hotplug callbacks

 - Fix a deadlock when an s390dbf debug area is unregistered while one
   of its debugfs files is being written to

 - Fix MVIY_PERCPU() with binutils older than 2.39, where an assembler
   macro silently omitted an instruction needed to repair interrupted
   operations after CPU migration

 - Remove/replace cond_resched() calls which are no-ops with the
   supported s390 preemption models

 - Fix AP queue depth and maximum message length decoding according to
   the architecture. Current hardware is not affected, but future
   hardware could report values which were handled incorrectly

 - Reflect the configured CPU state in cpu_enabled_mask so deconfigured
   CPUs are not presented as available for onlining

 - Restore the vDSO GNU_EH_FRAME program header which was lost when the
   build switched to direct linker invocation, and mark it read-only

 - Add SCLP action qualifiers used by Spyre for card initialization,
   recoverable error and telemetry reporting

 - Move KMSAN interrupt flag helpers out of line to fix
   -Wstatic-in-inline build warnings

 - Use level-specific page table entry accessors for hugetlb entries and
   ptep_get() when accessing crashed kernel memory in kdump

 - Make forced AP bus rescans killable so that a user process blocked
   behind an ongoing scan can still be terminated with SIGKILL

 - Rework pkey ioctl error paths to remove duplicated cleanup code and
   avoid freeing error pointers

 - Allow the protected guest SWIOTLB buffer to be allocated outside the
   first 2GB. Also enable dynamic SWIOTLB growth and the coherent atomic
   pool fallback to improve I/O behavior when the initial pool is
   exhausted

 - Add program check statistics and spinlock contention tracepoints.
   Increase the lockdep chain capacity to keep lockdep enabled for
   complex code paths such as btrfs

 - Simplify IPL, trap and syscall code and remove the obsolete
   unistd_32.h generation entry

* tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (59 commits)
  s390/percpu: Fix MVIY_PERCPU() with older binutils
  s390/debug: Fix deadlock during unregister
  s390/cpum_cf: Handle CPU hotplug via prepare/dead callbacks
  s390: Enable CONTEXT_ANALYSIS for various directories
  s390/mm: Add __context_unsafe() attribute to gmap helper functions
  s390/mm: Add __context_unsafe() attribute to do_secure_storage_access()
  s390/sysinfo: Add context analysis attributes
  s390/irqflags: Add out-of-line definitions of arch_local_irq_*() for KMSAN
  s390/virtio: Enable CONTEXT_ANALYSIS
  s390/cio: Enable CONTEXT_ANALYSIS
  s390/vfio_ccw: Add __must_hold() attribute to vfio_ccw_sch_quiesce()
  s390/pci: Enable CONTEXT_ANALYSIS
  s390/pci: Rework __zpci_event_availability() to remove conditional locking
  s390/pci: Rework __zpci_event_error() to remove conditional locking
  s390/char: Enable CONTEXT_ANALYSIS
  s390/con3215: Add __must_hold() attribute to raw3215_make_room()
  s390/ap: Fix MAPML computation
  s390/cio: Remove cond_resched() calls
  s390: Remove cond_resched() calls
  KVM: s390: Remove cond_resched() calls
  ...
2026-08-23 10:26:44 -07:00
Heiko Carstens
6e1eb66b0a s390/cio: Enable CONTEXT_ANALYSIS
All cio code passes clang's compile time context analysis.
Therefore enable CONTEXT_ANALYSIS.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-11 16:42:18 +02:00
Heiko Carstens
aa8db8e37e s390/vfio_ccw: Add __must_hold() attribute to vfio_ccw_sch_quiesce()
Add __must_hold() attribute to vfio_ccw_sch_quiesce() in order to let
clang's context analysis know that sch->lock must be held on function
entry. This can also be easily verified when inspecting the function.

Without this annotation this leads to a valid warning when context
analysis is enabled:

drivers/s390/cio/vfio_ccw_drv.c:55:9: warning:
  expecting spinlock 'sch->lock' to be held at start of each loop [-Wthread-safety-analysis]
   55 |                 ret = cio_cancel_halt_clear(sch, &iretry);
      |                       ^

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-11 16:42:17 +02:00
Heiko Carstens
5ddf6f12dc s390/cio: Remove cond_resched() calls
Since [1] cond_resched() is a no-op on s390. Remove all calls.

[1] commit 7dadeaa6e8 ("sched: Further restrict the preemption modes")

Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:16:54 +02:00
Eric Farman
16b0798024 s390/vfio_ccw: Implement a crw lock
Unlike the channel_program struct, which covers synchronous I/O
submissions and asynchronous interrupts, the CRW region relies
exclusively on asynchronous events coming from hardware.

Implement a lock to manage the list of those payloads, to ensure
they are read cohesively.

Fixes: 3f02cb2fd9 ("vfio-ccw: Wire up the CRW irq and CRW region")
Cc: stable@vger.kernel.org
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:50:48 +02:00
Eric Farman
34f4feff3e s390/vfio_ccw: Selectively expand io_mutex
The io_mutex was defined to serialize the io_regions, but then has
also sort of been associated with the I/O themselves because of
the close relationship they share.

With the handful of races that are possible, the choices are either to:
 A) expand the scope of io_mutex to close these remaining windows, or
 B) reduce the scope of io_mutex to just io_region, and introduce a new
    lock mechanism for the remaining I/O resources

This patch implements A, since B brings with it a lot more interactions
that would need to be tracked and kept in a correct hierarchy. It also
takes advantage of the workqueue element for cp_free() that now gets
called out of fsm_notoper(), which could be invoked out of an interrupt
context and thus cannot acquire a mutex itself.

Fixes: 4f76617378 ("vfio-ccw: protect the I/O region")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:50:43 +02:00
Eric Farman
0c11f61a87 s390/vfio_ccw: Move cp cleanup out of not operational
The fsm_notoper() routine is called when the device has been
lost, and is (by definition) no longer operational. Since this
can happen asynchronously from the normal behavior of the
driver, the cleanup may happen when holding other locks
in the calling sequence (notably, the cio subchannel lock).

Push the cleanup of the private->cp resources to a workqueue,
where it can be done out from under that lock sequence and
a future patch can safely manage the locking requirements.

Fixes: 204b394a23 ("vfio/ccw: Move FSM open/close to MDEV open/close")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:50:39 +02:00
Eric Farman
79c60b2c61 s390/vfio_ccw: Cancel existing workqueues
The initialization of the io_work and crw_work workqueues begs the
question of whether they should be un-initialized. Add the corresponding
cleanup tags in _release_dev to ensure work isn't dispatched after
the private struct is free'd.

Suggested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Fixes: e5f84dbaea ("vfio: ccw: return I/O results asynchronously")
Fixes: 3f02cb2fd9 ("vfio-ccw: Wire up the CRW irq and CRW region")
Cc: stable@vger.kernel.org
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:50:31 +02:00
Eric Farman
9f5f9a78fe s390/vfio_ccw: Ensure index for read/write regions are within range
The introduction of the capability chain rightly clamped the
region indexes to the range of the capabilities itself, but
neglected to do so for the existing read/write regions which
should also be enforced.

Fixes: db8e5d17ac ("vfio-ccw: add capabilities chain")
Cc: stable@vger.kernel.org
Cc: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:50:24 +02:00
Eric Farman
4f6fdc6e1a s390/vfio_ccw: Calculate idal length based on idaw type
Sashiko pointed out that get_guest_idal() unconditionally calculates
the length of the IDAL presuming everything is a Format-2 IDAW.

The output of vfio-ccw is always Format-2, but the input can be either
Format-1 (31-bit addresses) or Format-2 (64-bit addresses). As a result,
the size of the guest IDAL may be incorrect and should be trimmed down.

Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Link: https://lore.kernel.org/r/20260720203400.7328E1F000E9@smtp.kernel.org/
Fixes: 1b676fe3d9 ("vfio/ccw: handle a guest Format-1 IDAL")
Cc: stable@vger.kernel.org
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:50:19 +02:00
Eric Farman
565bef268d s390/vfio_ccw: Ensure first IDAW remains constant
The first IDAW in a list does not need to be on a 2K/4K boundary
like all others, and so is read separately to accurately calculate
the size of the buffer needed to read the full IDAL.

Verify that the address found in the first IDAW is unchanged between
reads, to ensure a consistent set of IDAWs being worked with.

Fixes: 01aa26c672 ("s390/cio: Combine direct and indirect CCW paths")
Cc: stable@vger.kernel.org
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:50:15 +02:00
Eric Farman
a005b7f1a4 s390/vfio_ccw: Fix out of bounds check on CCW array
The routine ccwchain_calc_length() counts the number of channel
command words (CCWs) that are chained together in a single channel
program, and rejects anything larger than CCWCHAIN_LEN_MAX (256) CCWs.

The loop itself is "do..while (count < 257)", and while the logic in
is_cpa_within_range() correctly adjusts between the 0-index array of
CCWs and the count of CCWs starting at 1, this means it would look
at a possible 257th CCW before ending the loop and (correctly)
returning an error.

Fix this by restructuring the loop to break as soon as 256 CCWs
(thus indexes 0-255) are examined, without looking at memory
outside the range.

Fixes: 0a19e61e6d ("vfio: ccw: introduce channel program interfaces")
Cc: stable@vger.kernel.org
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:50:11 +02:00
Eric Farman
5405c90d6a s390/vfio_ccw: Limit the number of channel program segments
The processing of channel programs, and the CCWs within them, is done
recursively. As such, there is an arbitrary (but not architectural)
limit to the number of CCWs that can exist in a single channel program.

The vfio-ccw logic breaks these channel programs into segments whenever
it encounters a Transfer-In-Channel (TIC) CCW, and the combined number
of segments count towards the global limit. Impose an equivalent limit
to the number of segments until such logic can be made non-recursive.

Fixes: 0a19e61e6d ("vfio: ccw: introduce channel program interfaces")
Cc: stable@vger.kernel.org
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:50:07 +02:00
Eric Farman
74186c2968 s390/vfio_ccw: Free all memory if cp_init() fails
The routine cp_free() is called to unpin/free any memory once an I/O
is completed successfully, or if cp_prefetch() fails. But if cp_init()
fails, and cp->initialized is not enabled, the same routine cannot be
used to free all the memory.

An attempt to address this exists in ccwchain_handle_ccw(), where a
single call to ccwchain_free() is made for the currently-processed
CCW segment. But this will leak other segments (created as a result
of a Transfer in Channel) that had been allocated as part of the same
channel program.

Address this by performing the cleanup outside of the recursive
ccwchain_handle_ccw()/ccwchain_loop_tic() logic.

Fixes: 8b515be512 ("vfio-ccw: Fix memory leak and don't call cp_free in cp_init")
Cc: stable@vger.kernel.org
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-30 19:49:49 +02:00
Alexander Gordeev
9fb519794e Merge branch 'idle-time-acc' into features
Heiko Carstens says:

===================
This is supposed to improve s390 idle time accounting, and brings it
back to the state it was before arch_cpu_idle_time() was removed from
s390 [3].

In result all cpu time accounting is done by the s390 architecture backend
again, instead of having a mix of architecure specific and common code
accounting (common code: idle, s390 architecture: everything else).
===================

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-16 16:21:46 +02:00
Linus Torvalds
25a01b5155 s390 updates for 7.2 merge window
- Use CIO device online variable instead of the internal FSM state to
   determine device availability during purge operations
 
 - Remove extra check of task_stack_page() because try_get_task_stack()
   already takes care of that when reading /proc/<pid>/wchan
 
 - Allow user-space to use the new SCLP action qualifier 4 for to
   provide NVMe SMART log data to the platform.
 
 - Send AP CHANGE uevents on successful bind and successful association
   to notify user-space about SE operations on AP queue devices
 
 - Add an s390dbf kernel parameter to configure debug log levels and
   area sizes during early boot
 
 - On arm64 the empty zero page is going to be mapped read-only.
   Do the same for s390 with an explicit set_memory_ro() call
 
 - Improve s390-specific bcr_serialize() and cpu_relax() implementations
 
 - Remove all unused variables to avoid allmodconfig W=1 build fails
   with latest clang-23
 
 - Cleanup default Kconfig values for s390 selftests
 
 - Add a s390-tod trace clock to allow comparing trace timestamps
   between different systems or virtual machines on s390
 
 - Remove the s390 implementation of strlcat() in favor of the
   generic variant
 
 - Make consistent the calling order between page_table_check_pte_clear()
   and secure page conversion across all code paths
 
 - Rearrange some fields within AP and zcrypt structs to reduce
   memory consumption and unused holes
 
 - Shorten GR_NUM and VX_NUM macros and move them to a separate header
 
 - Replace __get_free_page() with kmalloc() in few sources
 
 - Introduce an infrastructure for more efficient this_cpu operations.
   Eliminate conditional branches when PREEMPT_NONE is removed
 
 - Enable Rust support
 
 - Use z10 as minimum architecture level, similar to the boot code,
   to enforce a defined architecture level set
 
 - Improve and convert various mem*() helper functions to C. For that
   add .noinstr.text section to avoid orphaned warnings from the linker
 
 - Fix the function pointer type in __ret_from_fork() to correct
   the indirect call to match kernel thread return type of int
 
 - Revert support for DCACHE_WORD_ACCESS to avoid an endless exception
   loop on read from donated Ultravisor pages at unaligned addresses
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Merge tag 's390-7.2-1' of gitolite.kernel.org:pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Alexander Gordeev:

 - Use CIO device online variable instead of the internal FSM state to
   determine device availability during purge operations

 - Remove extra check of task_stack_page() because try_get_task_stack()
   already takes care of that when reading /proc/<pid>/wchan

 - Allow user-space to use the new SCLP action qualifier 4 for to
   provide NVMe SMART log data to the platform.

 - Send AP CHANGE uevents on successful bind and successful association
   to notify user-space about SE operations on AP queue devices

 - Add an s390dbf kernel parameter to configure debug log levels and
   area sizes during early boot

 - On arm64 the empty zero page is going to be mapped read-only. Do the
   same for s390 with an explicit set_memory_ro() call

 - Improve s390-specific bcr_serialize() and cpu_relax() implementations

 - Remove all unused variables to avoid allmodconfig W=1 build fails
   with latest clang-23

 - Cleanup default Kconfig values for s390 selftests

 - Add a s390-tod trace clock to allow comparing trace timestamps
   between different systems or virtual machines on s390

 - Remove the s390 implementation of strlcat() in favor of the generic
   variant

 - Make consistent the calling order between
   page_table_check_pte_clear() and secure page conversion across all
   code paths

 - Rearrange some fields within AP and zcrypt structs to reduce memory
   consumption and unused holes

 - Shorten GR_NUM and VX_NUM macros and move them to a separate header

 - Replace __get_free_page() with kmalloc() in few sources

 - Introduce an infrastructure for more efficient this_cpu operations.
   Eliminate conditional branches when PREEMPT_NONE is removed

 - Enable Rust support

 - Use z10 as minimum architecture level, similar to the boot code, to
   enforce a defined architecture level set

 - Improve and convert various mem*() helper functions to C. For that
   add .noinstr.text section to avoid orphaned warnings from the linker

 - Fix the function pointer type in __ret_from_fork() to correct the
   indirect call to match kernel thread return type of int

 - Revert support for DCACHE_WORD_ACCESS to avoid an endless exception
   loop on read from donated Ultravisor pages at unaligned addresses

* tag 's390-7.2-1' of gitolite.kernel.org:pub/scm/linux/kernel/git/s390/linux: (52 commits)
  s390: Revert support for DCACHE_WORD_ACCESS
  s390/process: Fix kernel thread function pointer type
  s390/tishift: Convert __ashlti3(), __ashrti3(), __lshrti3() to C
  s390/memmove: Optimize backward copy case
  s390/string: Convert memset(16|32|64)() to C
  s390/string: Convert memcpy() to C
  s390/string: Convert memset() to C
  s390/string: Convert memmove() to C
  s390/string: Add -ffreestanding compile option to string.o
  s390: Add .noinstr.text to boot and purgatory linker scripts
  s390/purgatory: Enforce z10 minimum architecture level
  s390: Enable Rust support
  s390/cmpxchg: Fix KASAN stack-out-of-bounds in atomic helpers
  rust: helpers: Add memchr wrapper for string operations
  rust/bindgen_parameters: Mark s390 types as opaque to prevent repr conflicts
  s390/jump_label: Implement ARCH_STATIC_BRANCH_JUMP_ASM and ARCH_STATIC_BRANCH_ASM macros
  s390/bug: Provide ARCH_WARN_ASM for Rust WARN/BUG support
  s390/ap: Fix locking issue in SE bind and associate sysfs functions
  s390/percpu: Provide arch_this_cpu_write() implementation
  s390/percpu: Provide arch_this_cpu_read() implementation
  ...
2026-06-16 05:08:13 +05:30
Heiko Carstens
4fe307f0f5 s390/irq/idle: Use stcke instead of stckf for time stamps
The upcoming cpu idle time accounting rework involves comparing and
subtracting cross cpu time stamps. Time stamps created with the stckf
instruction monotonic with respect to the local cpu. For cross cpu
monotonic time stamps the slightly slower stcke instruction has to
be used [1].

Convert the idle time accounting relevant usages of stckf to stcke.

[1] Principles of Operation - Setting and Inspecting the Clock

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-15 16:33:40 +02:00
Peter Oberparleiter
ea34567db0 s390/cio: Restore GFP_DMA for CHSC allocation
Re-add GFP_DMA when allocating memory for CHSC control blocks.
On some supported machines, CHSC cannot access memory outside
the DMA zone, causing CHSC command failures.

Cc: stable@vger.kernel.org
Fixes: a3a64a4def ("s390/cio: remove unneeded DMA zone allocation")
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-11 16:27:25 +02:00
Vineeth Vijayan
58d50cad63 s390/cio: Purge based on the cdev's online status
Ensure that all devices currently offline are purged correctly.

Previously, purging logic relied on the internal FSM state to
determine whether a device was offline. However, devices with a
target state of offline could be skipped if CIO internal
processing was still ongoing during the purge operation.

Update the purge decision logic to rely on the online variable
in the cdev structure instead of the internal FSM state,
providing a more reliable indication of actual device
availability.

Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-05-05 10:12:47 +02:00
Danilo Krummrich
ac4d8bb6e2 s390/cio: use generic driver_override infrastructure
When a driver is probed through __driver_attach(), the bus' match()
callback is called without the device lock held, thus accessing the
driver_override field without a lock, which can cause a UAF.

Fix this by using the driver-core driver_override infrastructure taking
care of proper locking internally.

Note that calling match() from __driver_attach() without the device lock
held is intentional. [1]

Link: https://lore.kernel.org/driver-core/DGRGTIRHA62X.3RY09D9SOK77P@kernel.org/ [1]
Reported-by: Gui-Dong Han <hanguidong02@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220789
Fixes: ebc3d17915 ("s390/cio: introduce driver_override on the css bus")
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Link: https://patch.msgid.link/20260324005919.2408620-10-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-04-04 00:48:40 +02:00
Linus Torvalds
32a92f8c89 Convert more 'alloc_obj' cases to default GFP_KERNEL arguments
This converts some of the visually simpler cases that have been split
over multiple lines.  I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.

Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script.  I probably had made it a bit _too_ trivial.

So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.

The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 20:03:00 -08:00
Linus Torvalds
323bbfcf1e Convert 'alloc_flex' family to use the new default GFP_KERNEL argument
This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.

As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Linus Torvalds
136114e0ab mm.git review status for linus..mm-nonmm-stable
Total patches:       107
 Reviews/patch:       1.07
 Reviewed rate:       67%
 
 - The 2 patch series "ocfs2: give ocfs2 the ability to reclaim
   suballocator free bg" from Heming Zhao saves disk space by teaching
   ocfs2 to reclaim suballocator block group space.
 
 - The 4 patch series "Add ARRAY_END(), and use it to fix off-by-one
   bugs" from Alejandro Colomar adds the ARRAY_END() macro and uses it in
   various places.
 
 - The 2 patch series "vmcoreinfo: support VMCOREINFO_BYTES larger than
   PAGE_SIZE" from Pnina Feder makes the vmcore code future-safe, if
   VMCOREINFO_BYTES ever exceeds the page size.
 
 - The 7 patch series "kallsyms: Prevent invalid access when showing
   module buildid" from Petr Mladek cleans up kallsyms code related to
   module buildid and fixes an invalid access crash when printing
   backtraces.
 
 - The 3 patch series "Address page fault in
   ima_restore_measurement_list()" from Harshit Mogalapalli fixes a
   kexec-related crash that can occur when booting the second-stage kernel
   on x86.
 
 - The 6 patch series "kho: ABI headers and Documentation updates" from
   Mike Rapoport updates the kexec handover ABI documentation.
 
 - The 4 patch series "Align atomic storage" from Finn Thain adds the
   __aligned attribute to atomic_t and atomic64_t definitions to get
   natural alignment of both types on csky, m68k, microblaze, nios2,
   openrisc and sh.
 
 - The 2 patch series "kho: clean up page initialization logic" from
   Pratyush Yadav simplifies the page initialization logic in
   kho_restore_page().
 
 - The 6 patch series "Unload linux/kernel.h" from Yury Norov moves
   several things out of kernel.h and into more appropriate places.
 
 - The 7 patch series "don't abuse task_struct.group_leader" from Oleg
   Nesterov removes the usage of ->group_leader when it is "obviously
   unnecessary".
 
 - The 5 patch series "list private v2 & luo flb" from Pasha Tatashin
   adds some infrastructure improvements to the live update orchestrator.
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Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves
   disk space by teaching ocfs2 to reclaim suballocator block group
   space (Heming Zhao)

 - "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the
   ARRAY_END() macro and uses it in various places (Alejandro Colomar)

 - "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes
   the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the
   page size (Pnina Feder)

 - "kallsyms: Prevent invalid access when showing module buildid" cleans
   up kallsyms code related to module buildid and fixes an invalid
   access crash when printing backtraces (Petr Mladek)

 - "Address page fault in ima_restore_measurement_list()" fixes a
   kexec-related crash that can occur when booting the second-stage
   kernel on x86 (Harshit Mogalapalli)

 - "kho: ABI headers and Documentation updates" updates the kexec
   handover ABI documentation (Mike Rapoport)

 - "Align atomic storage" adds the __aligned attribute to atomic_t and
   atomic64_t definitions to get natural alignment of both types on
   csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain)

 - "kho: clean up page initialization logic" simplifies the page
   initialization logic in kho_restore_page() (Pratyush Yadav)

 - "Unload linux/kernel.h" moves several things out of kernel.h and into
   more appropriate places (Yury Norov)

 - "don't abuse task_struct.group_leader" removes the usage of
   ->group_leader when it is "obviously unnecessary" (Oleg Nesterov)

 - "list private v2 & luo flb" adds some infrastructure improvements to
   the live update orchestrator (Pasha Tatashin)

* tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits)
  watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency
  procfs: fix missing RCU protection when reading real_parent in do_task_stat()
  watchdog/softlockup: fix sample ring index wrap in need_counting_irqs()
  kcsan, compiler_types: avoid duplicate type issues in BPF Type Format
  kho: fix doc for kho_restore_pages()
  tests/liveupdate: add in-kernel liveupdate test
  liveupdate: luo_flb: introduce File-Lifecycle-Bound global state
  liveupdate: luo_file: Use private list
  list: add kunit test for private list primitives
  list: add primitives for private list manipulations
  delayacct: fix uapi timespec64 definition
  panic: add panic_force_cpu= parameter to redirect panic to a specific CPU
  netclassid: use thread_group_leader(p) in update_classid_task()
  RDMA/umem: don't abuse current->group_leader
  drm/pan*: don't abuse current->group_leader
  drm/amd: kill the outdated "Only the pthreads threading model is supported" checks
  drm/amdgpu: don't abuse current->group_leader
  android/binder: use same_thread_group(proc->tsk, current) in binder_mmap()
  android/binder: don't abuse current->group_leader
  kho: skip memoryless NUMA nodes when reserving scratch areas
  ...
2026-02-12 12:13:01 -08:00
Salah Triki
f65c75b0b9 s390/cio: Fix device lifecycle handling in css_alloc_subchannel()
`css_alloc_subchannel()` calls `device_initialize()` before setting up
the DMA masks. If `dma_set_coherent_mask()` or `dma_set_mask()` fails,
the error path frees the subchannel structure directly, bypassing
the device model reference counting.

Once `device_initialize()` has been called, the embedded struct device
must be released via `put_device()`, allowing the release callback to
free the container structure.

Fix the error path by dropping the initial device reference with
`put_device()` instead of calling `kfree()` directly.

This ensures correct device lifetime handling and avoids potential
use-after-free or double-free issues.

Fixes: e5dcf0025d ("s390/css: move subchannel lock allocation")
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-02-05 13:02:48 +01:00
Randy Dunlap
24c776355f kernel.h: drop hex.h and update all hex.h users
Remove <linux/hex.h> from <linux/kernel.h> and update all users/callers of
hex.h interfaces to directly #include <linux/hex.h> as part of the process
of putting kernel.h on a diet.

Removing hex.h from kernel.h means that 36K C source files don't have to
pay the price of parsing hex.h for the roughly 120 C source files that
need it.

This change has been build-tested with allmodconfig on most ARCHes.  Also,
all users/callers of <linux/hex.h> in the entire source tree have been
updated if needed (if not already #included).

Link: https://lkml.kernel.org/r/20251215005206.2362276-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20 19:44:19 -08:00
Linus Torvalds
a3ebb59eee VFIO updates for v6.19-rc1
- Move libvfio selftest artifacts in preparation of more tightly
    coupled integration with KVM selftests. (David Matlack)
 
  - Fix comment typo in mtty driver. (Chu Guangqing)
 
  - Support for new hardware revision in the hisi_acc vfio-pci variant
    driver where the migration registers can now be accessed via the PF.
    When enabled for this support, the full BAR can be exposed to the
    user. (Longfang Liu)
 
  - Fix vfio cdev support for VF token passing, using the correct size
    for the kernel structure, thereby actually allowing userspace to
    provide a non-zero UUID token.  Also set the match token callback for
    the hisi_acc, fixing VF token support for this this vfio-pci variant
    driver. (Raghavendra Rao Ananta)
 
  - Introduce internal callbacks on vfio devices to simplify and
    consolidate duplicate code for generating VFIO_DEVICE_GET_REGION_INFO
    data, removing various ioctl intercepts with a more structured
    solution. (Jason Gunthorpe)
 
  - Introduce dma-buf support for vfio-pci devices, allowing MMIO regions
    to be exposed through dma-buf objects with lifecycle managed through
    move operations.  This enables low-level interactions such as a
    vfio-pci based SPDK drivers interacting directly with dma-buf capable
    RDMA devices to enable peer-to-peer operations.  IOMMUFD is also now
    able to build upon this support to fill a long standing feature gap
    versus the legacy vfio type1 IOMMU backend with an implementation of
    P2P support for VM use cases that better manages the lifecycle of the
    P2P mapping. (Leon Romanovsky, Jason Gunthorpe, Vivek Kasireddy)
 
  - Convert eventfd triggering for error and request signals to use RCU
    mechanisms in order to avoid a 3-way lockdep reported deadlock issue.
    (Alex Williamson)
 
  - Fix a 32-bit overflow introduced via dma-buf support manifesting with
    large DMA buffers. (Alex Mastro)
 
  - Convert nvgrace-gpu vfio-pci variant driver to insert mappings on
    fault rather than at mmap time.  This conversion serves both to make
    use of huge PFNMAPs but also to both avoid corrected RAS events
    during reset by now being subject to vfio-pci-core's use of
    unmap_mapping_range(), and to enable a device readiness test after
    reset. (Ankit Agrawal)
 
  - Refactoring of vfio selftests to support multi-device tests and split
    code to provide better separation between IOMMU and device objects.
    This work also enables a new test suite addition to measure parallel
    device initialization latency. (David Matlack)
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Merge tag 'vfio-v6.19-rc1' of https://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Move libvfio selftest artifacts in preparation of more tightly
   coupled integration with KVM selftests (David Matlack)

 - Fix comment typo in mtty driver (Chu Guangqing)

 - Support for new hardware revision in the hisi_acc vfio-pci variant
   driver where the migration registers can now be accessed via the PF.
   When enabled for this support, the full BAR can be exposed to the
   user (Longfang Liu)

 - Fix vfio cdev support for VF token passing, using the correct size
   for the kernel structure, thereby actually allowing userspace to
   provide a non-zero UUID token. Also set the match token callback for
   the hisi_acc, fixing VF token support for this this vfio-pci variant
   driver (Raghavendra Rao Ananta)

 - Introduce internal callbacks on vfio devices to simplify and
   consolidate duplicate code for generating VFIO_DEVICE_GET_REGION_INFO
   data, removing various ioctl intercepts with a more structured
   solution (Jason Gunthorpe)

 - Introduce dma-buf support for vfio-pci devices, allowing MMIO regions
   to be exposed through dma-buf objects with lifecycle managed through
   move operations. This enables low-level interactions such as a
   vfio-pci based SPDK drivers interacting directly with dma-buf capable
   RDMA devices to enable peer-to-peer operations. IOMMUFD is also now
   able to build upon this support to fill a long standing feature gap
   versus the legacy vfio type1 IOMMU backend with an implementation of
   P2P support for VM use cases that better manages the lifecycle of the
   P2P mapping (Leon Romanovsky, Jason Gunthorpe, Vivek Kasireddy)

 - Convert eventfd triggering for error and request signals to use RCU
   mechanisms in order to avoid a 3-way lockdep reported deadlock issue
   (Alex Williamson)

 - Fix a 32-bit overflow introduced via dma-buf support manifesting with
   large DMA buffers (Alex Mastro)

 - Convert nvgrace-gpu vfio-pci variant driver to insert mappings on
   fault rather than at mmap time. This conversion serves both to make
   use of huge PFNMAPs but also to both avoid corrected RAS events
   during reset by now being subject to vfio-pci-core's use of
   unmap_mapping_range(), and to enable a device readiness test after
   reset (Ankit Agrawal)

 - Refactoring of vfio selftests to support multi-device tests and split
   code to provide better separation between IOMMU and device objects.
   This work also enables a new test suite addition to measure parallel
   device initialization latency (David Matlack)

* tag 'vfio-v6.19-rc1' of https://github.com/awilliam/linux-vfio: (65 commits)
  vfio: selftests: Add vfio_pci_device_init_perf_test
  vfio: selftests: Eliminate INVALID_IOVA
  vfio: selftests: Split libvfio.h into separate header files
  vfio: selftests: Move vfio_selftests_*() helpers into libvfio.c
  vfio: selftests: Rename vfio_util.h to libvfio.h
  vfio: selftests: Stop passing device for IOMMU operations
  vfio: selftests: Move IOVA allocator into iova_allocator.c
  vfio: selftests: Move IOMMU library code into iommu.c
  vfio: selftests: Rename struct vfio_dma_region to dma_region
  vfio: selftests: Upgrade driver logging to dev_err()
  vfio: selftests: Prefix logs with device BDF where relevant
  vfio: selftests: Eliminate overly chatty logging
  vfio: selftests: Support multiple devices in the same container/iommufd
  vfio: selftests: Introduce struct iommu
  vfio: selftests: Rename struct vfio_iommu_mode to iommu_mode
  vfio: selftests: Allow passing multiple BDFs on the command line
  vfio: selftests: Split run.sh into separate scripts
  vfio: selftests: Move run.sh into scripts directory
  vfio/nvgrace-gpu: wait for the GPU mem to be ready
  vfio/nvgrace-gpu: Inform devmem unmapped after reset
  ...
2025-12-04 18:42:48 -08:00
Heiko Carstens
c3d17464f0 s390: Remove KMSG_COMPONENT macro
The KMSG_COMPONENT macro is a leftover of the s390 specific "kernel
message catalog" which never made it upstream.

Remove the macro in order to get rid of a pointless indirection. Replace
all users with the string it defines. In almost all cases this leads to a
simple replacement like this:

 - #define KMSG_COMPONENT "appldata"
 - #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 + #define pr_fmt(fmt) "appldata: " fmt

Except for some special cases this is just mechanical/scripted work.

Acked-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-11-24 11:45:21 +01:00
Heiko Carstens
8e0b986c59 s390: Remove compat support
There shouldn't be any 31 bit code around anymore that matters.
Remove the compat layer support required to run 31 bit code.

Reason for removal is code simplification and reduced test effort.

Note that this comes without any deprecation warnings added to config
options, or kernel messages, since most likely those would be ignored
anyway.

If it turns out there is still a reason to keep the compat layer this
can be reverted at any time in the future.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-11-17 11:10:38 +01:00
Jason Gunthorpe
973af0c40e vfio/ccw: Convert to get_region_info_caps
Remove the duplicate code and flatten the call chain.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Link: https://lore.kernel.org/r/18-v2-2a9e24d62f1b+e10a-vfio_get_region_info_op_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
2025-11-12 15:05:03 -07:00
Jason Gunthorpe
61b3f7b5a7 vfio/ccw: Provide a get_region_info op
Move it out of vfio_ccw_mdev_ioctl() and re-indent it.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Link: https://lore.kernel.org/r/12-v2-2a9e24d62f1b+e10a-vfio_get_region_info_op_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
2025-11-12 15:05:02 -07:00
Heiko Carstens
ba06238bbe s390/cio: Use scnprintf() instead of sprintf()
Use scnprintf() instead of sprintf() for those cases where the destination
is an array and the size of the array is known at compile time.

This prevents theoretical buffer overflows, but also avoids that people
again and again spend time to figure out if the code is actually safe.

Reviewed-by: Jan Polensky <japo@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-10-21 10:17:30 +02:00
Vineeth Vijayan
9daa5a8795 s390/cio: Update purge function to unregister the unused subchannels
Starting with 'commit 2297791c92 ("s390/cio: dont unregister
subchannel from child-drivers")', cio no longer unregisters
subchannels when the attached device is invalid or unavailable.

As an unintended side-effect, the cio_ignore purge function no longer
removes subchannels for devices on the cio_ignore list if no CCW device
is attached. This situation occurs when a CCW device is non-operational
or unavailable

To ensure the same outcome of the purge function as when the
current cio_ignore list had been active during boot, update the purge
function to remove I/O subchannels without working CCW devices if the
associated device number is found on the cio_ignore list.

Fixes: 2297791c92 ("s390/cio: dont unregister subchannel from child-drivers")
Suggested-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2025-10-04 18:40:42 +02:00
Heiko Carstens
4335edb713 s390: Remove superfluous newlines from inline assemblies
Remove superfluous newlines from inline assemblies. Compilers use the
number of lines of inline assemblies as heuristic for the complexity
and inline decisions. Therefore inline assemblies should only contain
as many lines as required.

A lot of inline assemblies contain a superfluous newline for the last
line. Remove such newlines to improve compiler inlining decisions.

Suggested-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-09-29 13:52:08 +02:00
Heiko Carstens
f0edc8f113 s390/cio/ioasm: Fix __xsch() condition code handling
For the __xsch() inline assembly the conversion to flag output macros is
incomplete. Only the conditional shift of the return value was added, while
the required changes to the inline assembly itself are missing.

If compiled with GCC versions before 14.2 this leads to a double shift of
the cc output operand and therefore the returned value of __xsch() is
incorrectly always zero, instead of the expected condition code.

Fixes: e200565d43 ("s390/cio/ioasm: Convert to use flag output macros")
Cc: stable@vger.kernel.org
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-09-29 13:52:08 +02:00
Linus Torvalds
bc46b7cbc5 s390 updates for 6.17 merge window
- Standardize on the __ASSEMBLER__ macro that is provided by GCC
   and Clang compilers and replace __ASSEMBLY__ with  __ASSEMBLER__
   in both uapi and non-uapi headers
 
 - Explicitly include <linux/export.h> in architecture and driver
   files which contain an EXPORT_SYMBOL() and remove the include
   from the files which do not contain the EXPORT_SYMBOL()
 
 - Use the full title of "z/Architecture Principles of Operation"
   manual and the name of a section where facility bits are listed
 
 - Use -D__DISABLE_EXPORTS for files in arch/s390/boot to avoid
   unnecessary slowing down of the build and confusing external
   kABI tools that process symtypes data
 
 - Print additional unrecoverable machine check information to make
   the root cause analysis easier
 
 - Move cmpxchg_user_key() handling to uaccess library code, since
   the generated code is large anyway and there is no benefit if it
   is inlined
 
 - Fix a problem when cmpxchg_user_key() is executing a code with a
   non-default key: if a system is IPL-ed with "LOAD NORMAL", and
   the previous system used storage keys where the fetch-protection
   bit was set for some pages, and the cmpxchg_user_key() is located
   within such page, a protection exception happens
 
 - Either the external call or emergency signal order is used to send
   an IPI to a remote CPU. Use the external order only, since it is at
   least as good and sometimes even better, than the emergency signal
 
 - In case of an early crash the early program check handler prints
   more or less random value of the last breaking event address, since
   it is not initialized properly. Copy the last breaking event address
   from the lowcore to pt_regs to address this
 
 - During STP synchronization check udelay() can not be used, since the
   first CPU modifies tod_clock_base and get_tod_clock_monotonic() might
   return a non-monotonic time. Instead, busy-loop on other CPUs, while
   the the first CPU actually handles the synchronization operation
 
 - When debugging the early kernel boot using QEMU with the -S flag and
   GDB attached, skip the decompressor and start directly in kernel
 
 - Rename PAI Crypto event 4210 according to z16 and z17 "z/Architecture
   Principles of Operation" manual
 
 - Remove the in-kernel time steering support in favour of the new s390
   PTP driver, which allows the kernel clock steered more precisely
 
 - Remove a possible false-positive warning in pte_free_defer(), which
   could be triggered in a valid case KVM guest process is initializing
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Merge tag 's390-6.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Alexander Gordeev:

 - Standardize on the __ASSEMBLER__ macro that is provided by GCC and
   Clang compilers and replace __ASSEMBLY__ with __ASSEMBLER__ in both
   uapi and non-uapi headers

 - Explicitly include <linux/export.h> in architecture and driver files
   which contain an EXPORT_SYMBOL() and remove the include from the
   files which do not contain the EXPORT_SYMBOL()

 - Use the full title of "z/Architecture Principles of Operation" manual
   and the name of a section where facility bits are listed

 - Use -D__DISABLE_EXPORTS for files in arch/s390/boot to avoid
   unnecessary slowing down of the build and confusing external kABI
   tools that process symtypes data

 - Print additional unrecoverable machine check information to make the
   root cause analysis easier

 - Move cmpxchg_user_key() handling to uaccess library code, since the
   generated code is large anyway and there is no benefit if it is
   inlined

 - Fix a problem when cmpxchg_user_key() is executing a code with a
   non-default key: if a system is IPL-ed with "LOAD NORMAL", and the
   previous system used storage keys where the fetch-protection bit was
   set for some pages, and the cmpxchg_user_key() is located within such
   page, a protection exception happens

 - Either the external call or emergency signal order is used to send an
   IPI to a remote CPU. Use the external order only, since it is at
   least as good and sometimes even better, than the emergency signal

 - In case of an early crash the early program check handler prints more
   or less random value of the last breaking event address, since it is
   not initialized properly. Copy the last breaking event address from
   the lowcore to pt_regs to address this

 - During STP synchronization check udelay() can not be used, since the
   first CPU modifies tod_clock_base and get_tod_clock_monotonic() might
   return a non-monotonic time. Instead, busy-loop on other CPUs, while
   the the first CPU actually handles the synchronization operation

 - When debugging the early kernel boot using QEMU with the -S flag and
   GDB attached, skip the decompressor and start directly in kernel

 - Rename PAI Crypto event 4210 according to z16 and z17 "z/Architecture
   Principles of Operation" manual

 - Remove the in-kernel time steering support in favour of the new s390
   PTP driver, which allows the kernel clock steered more precisely

 - Remove a possible false-positive warning in pte_free_defer(), which
   could be triggered in a valid case KVM guest process is initializing

* tag 's390-6.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (29 commits)
  s390/mm: Remove possible false-positive warning in pte_free_defer()
  s390/stp: Default to enabled
  s390/stp: Remove leap second support
  s390/time: Remove in-kernel time steering
  s390/sclp: Use monotonic clock in sclp_sync_wait()
  s390/smp: Use monotonic clock in smp_emergency_stop()
  s390/time: Use monotonic clock in get_cycles()
  s390/pai_crypto: Rename PAI Crypto event 4210
  scripts/gdb/symbols: make lx-symbols skip the s390 decompressor
  s390/boot: Introduce jump_to_kernel() function
  s390/stp: Remove udelay from stp_sync_clock()
  s390/early: Copy last breaking event address to pt_regs
  s390/smp: Remove conditional emergency signal order code usage
  s390/uaccess: Merge cmpxchg_user_key() inline assemblies
  s390/uaccess: Prevent kprobes on cmpxchg_user_key() functions
  s390/uaccess: Initialize code pages executed with non-default access key
  s390/skey: Provide infrastructure for executing with non-default access key
  s390/uaccess: Make cmpxchg_user_key() library code
  s390/page: Add memory clobber to page_set_storage_key()
  s390/page: Cleanup page_set_storage_key() inline assemblies
  ...
2025-07-29 20:17:08 -07:00
Heiko Carstens
7ecc694883 s390/drivers: Remove unnecessary include <linux/export.h>
Remove include <linux/export.h> from all files which do not contain an
EXPORT_SYMBOL().

See commit 7d95680d64 ("scripts/misc-check: check unnecessary #include
<linux/export.h> when W=1") for more details.

Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-06-17 18:18:03 +02:00
Heiko Carstens
8a56977051 s390/drivers: Explicitly include <linux/export.h>
Explicitly include <linux/export.h> in files which contain an
EXPORT_SYMBOL().

See commit a934a57a42 ("scripts/misc-check: check missing #include
<linux/export.h> when W=1") for more details.

Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-06-17 18:18:02 +02:00
Thomas Weißschuh
fb506e31b3 sysfs: treewide: switch back to attribute_group::bin_attrs
The normal bin_attrs field can now handle const pointers.
This makes the _new variant unnecessary.
Switch all users back.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20250530-sysfs-const-bin_attr-final-v3-4-724bfcf05b99@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-17 10:44:15 +02:00
Ingo Molnar
41cb08555c treewide, timers: Rename from_timer() to timer_container_of()
Move this API to the canonical timer_*() namespace.

[ tglx: Redone against pre rc1 ]

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com
2025-06-08 09:07:37 +02:00
Thomas Gleixner
8fa7292fee treewide: Switch/rename to timer_delete[_sync]()
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-04-05 10:30:12 +02:00
Linus Torvalds
f90f2145b2 s390 updates for 6.15 merge window
- Add sorting of mcount locations at build time
 
 - Rework uaccess functions with C exception handling to shorten inline
   assembly size and enable full inlining. This yields near-optimal code
   for small constant copies with a ~40kb kernel size increase
 
 - Add support for a configurable STRICT_MM_TYPECHECKS which allows to
   generate better code, but also allows to have type checking for
   debug builds
 
 - Optimize get_lowcore() for common callers with alternatives that
   nearly revert to the pre-relocated lowcore code, while also slightly
   reducing syscall entry and exit time
 
 - Convert MACHINE_HAS_* checks for single facility tests into cpu_has_*
   style macros that call test_facility(), and for features with additional
   conditions, add a new ALT_TYPE_FEATURE alternative to provide a static
   branch via alternative patching. Also, move machine feature detection
   to the decompressor for early patching and add debugging functionality
   to easily show which alternatives are patched
 
 - Add exception table support to early boot / startup code to get rid
   of the open coded exception handling
 
 - Use asm_inline for all inline assemblies with EX_TABLE or ALTERNATIVE
   to ensure correct inlining and unrolling decisions
 
 - Remove 2k page table leftovers now that s390 has been switched to
   always allocate 4k page tables
 
 - Split kfence pool into 4k mappings in arch_kfence_init_pool() and
   remove the architecture-specific kfence_split_mapping()
 
 - Use READ_ONCE_NOCHECK() in regs_get_kernel_stack_nth() to silence
   spurious KASAN warnings from opportunistic ftrace argument tracing
 
 - Force __atomic_add_const() variants on s390 to always return void,
   ensuring compile errors for improper usage
 
 - Remove s390's ioremap_wt() and pgprot_writethrough() due to mismatched
   semantics and lack of known users, relying on asm-generic fallbacks
 
 - Signal eventfd in vfio-ap to notify userspace when the guest AP
   configuration changes, including during mdev removal
 
 - Convert mdev_types from an array to a pointer in vfio-ccw and vfio-ap
   drivers to avoid fake flex array confusion
 
 - Cleanup trap code
 
 - Remove references to the outdated linux390@de.ibm.com address
 
 - Other various small fixes and improvements all over the code
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Merge tag 's390-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add sorting of mcount locations at build time

 - Rework uaccess functions with C exception handling to shorten inline
   assembly size and enable full inlining. This yields near-optimal code
   for small constant copies with a ~40kb kernel size increase

 - Add support for a configurable STRICT_MM_TYPECHECKS which allows to
   generate better code, but also allows to have type checking for debug
   builds

 - Optimize get_lowcore() for common callers with alternatives that
   nearly revert to the pre-relocated lowcore code, while also slightly
   reducing syscall entry and exit time

 - Convert MACHINE_HAS_* checks for single facility tests into cpu_has_*
   style macros that call test_facility(), and for features with
   additional conditions, add a new ALT_TYPE_FEATURE alternative to
   provide a static branch via alternative patching. Also, move machine
   feature detection to the decompressor for early patching and add
   debugging functionality to easily show which alternatives are patched

 - Add exception table support to early boot / startup code to get rid
   of the open coded exception handling

 - Use asm_inline for all inline assemblies with EX_TABLE or ALTERNATIVE
   to ensure correct inlining and unrolling decisions

 - Remove 2k page table leftovers now that s390 has been switched to
   always allocate 4k page tables

 - Split kfence pool into 4k mappings in arch_kfence_init_pool() and
   remove the architecture-specific kfence_split_mapping()

 - Use READ_ONCE_NOCHECK() in regs_get_kernel_stack_nth() to silence
   spurious KASAN warnings from opportunistic ftrace argument tracing

 - Force __atomic_add_const() variants on s390 to always return void,
   ensuring compile errors for improper usage

 - Remove s390's ioremap_wt() and pgprot_writethrough() due to
   mismatched semantics and lack of known users, relying on asm-generic
   fallbacks

 - Signal eventfd in vfio-ap to notify userspace when the guest AP
   configuration changes, including during mdev removal

 - Convert mdev_types from an array to a pointer in vfio-ccw and vfio-ap
   drivers to avoid fake flex array confusion

 - Cleanup trap code

 - Remove references to the outdated linux390@de.ibm.com address

 - Other various small fixes and improvements all over the code

* tag 's390-6.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (78 commits)
  s390: Use inline qualifier for all EX_TABLE and ALTERNATIVE inline assemblies
  s390/kfence: Split kfence pool into 4k mappings in arch_kfence_init_pool()
  s390/ptrace: Avoid KASAN false positives in regs_get_kernel_stack_nth()
  s390/boot: Ignore vmlinux.map
  s390/sysctl: Remove "vm/allocate_pgste" sysctl
  s390: Remove 2k vs 4k page table leftovers
  s390/tlb: Use mm_has_pgste() instead of mm_alloc_pgste()
  s390/lowcore: Use lghi instead llilh to clear register
  s390/syscall: Merge __do_syscall() and do_syscall()
  s390/spinlock: Implement SPINLOCK_LOCKVAL with inline assembly
  s390/smp: Implement raw_smp_processor_id() with inline assembly
  s390/current: Implement current with inline assembly
  s390/lowcore: Use inline qualifier for get_lowcore() inline assembly
  s390: Move s390 sysctls into their own file under arch/s390
  s390/syscall: Simplify syscall_get_arguments()
  s390/vfio-ap: Notify userspace that guest's AP config changed when mdev removed
  s390: Remove ioremap_wt() and pgprot_writethrough()
  s390/mm: Add configurable STRICT_MM_TYPECHECKS
  s390/mm: Convert pgste_val() into function
  s390/mm: Convert pgprot_val() into function
  ...
2025-03-29 11:59:43 -07:00
Heiko Carstens
0dafe9968a s390: Use inline qualifier for all EX_TABLE and ALTERNATIVE inline assemblies
Use asm_inline for all inline assemblies which make use of the EX_TABLE or
ALTERNATIVE macros.

These macros expand to many lines and the compiler assumes the number of
lines within an inline assembly is the same as the number of instructions
within an inline assembly. This has an effect on inlining and loop
unrolling decisions.

In order to avoid incorrect assumptions use asm_inline, which tells the
compiler that an inline assembly has the smallest possible size.

In order to avoid confusion when asm_inline should be used or not, since a
couple of inline assemblies are quite large: the rule is to always use
asm_inline whenever the EX_TABLE or ALTERNATIVE macro is used. In specific
cases there may be reasons to not follow this guideline, but that should
be documented with the corresponding code.

Using the inline qualifier everywhere has only a small effect on the kernel
image size:

add/remove: 0/10 grow/shrink: 19/8 up/down: 1492/-1858 (-366)

The only location where this seems to matter is load_unaligned_zeropad()
from word-at-a-time.h where the compiler inlines more functions within the
dcache code, which is indeed code where performance matters.

Suggested-by: Juergen Christ <jchrist@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-18 17:13:51 +01:00
Heiko Carstens
52109a067a s390: Convert MACHINE_IS_[LPAR|VM|KVM], etc, machine_is_[lpar|vm|kvm]()
Move machine type detection to the decompressor and use static branches
to implement and use machine_is_[lpar|vm|kvm]() instead of a runtime check
via MACHINE_IS_[LPAR|VM|KVM].

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-04 17:18:07 +01:00