Commit Graph

1536 Commits

Author SHA1 Message Date
Linus Torvalds
1fc5a74b10 kmalloc_obj conversions for v7.3-rc2
- Run scripts/coccinelle/api/kmalloc_objs.cocci for v7.3
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRSPkdeREjth1dHnSE2KwveOeQkuwUCapuwVwAKCRA2KwveOeQk
 u5EeAP9TS7K4iVlw3KlZHuLIK2q+CQfALPepcu+ME2lO5dta4gEAxCTi0ZXmU7OT
 XbmWUd+DTkKNYCBW8E6Lvn72Er13uQs=
 =ZtN4
 -----END PGP SIGNATURE-----

Merge tag 'kmalloc_obj-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull kmalloc_obj conversions from Kees Cook:
 "Another run of the Coccinelle script for converting kmalloc()
  family of allocations to kmalloc_obj() via the existing rules
  in scripts/coccinelle/api/kmalloc_objs.cocci"

* tag 'kmalloc_obj-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  treewide: refresh kmalloc_obj() conversions
  drm/amd/display: Fix harmless type mismatch in allocation
2026-09-05 20:45:18 -07:00
Kees Cook
3a2c4d55e3 treewide: refresh kmalloc_obj() conversions
This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci

This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.

Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.

Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-09-04 21:37:00 -07:00
Tao Cui
9296375902 LoongArch: KVM: Fix TOCTOU race on pv_features
In kvm_loongarch_cpucfg_set_attr() the check-then-set on
kvm->arch.pv_features is lockless, so two vCPUs can race past the
validation and set different values. Add a spinlock to protect it.

Cc: stable@vger.kernel.org
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:45:13 +08:00
Zeng Chi
501514d6eb LoongArch: KVM: Validate MSI data before routing it to EIOINTC
pch_msi_set_irq() passes e->msi.data straight into eiointc_set_irq() as
the irq number. The MSI data comes from userspace, that either via a
KVM_IRQ_ROUTING_MSI entry set with KVM_SET_GSI_ROUTING (used by irqfd
and KVM_IRQ_LINE) or directly via KVM_SIGNAL_MSI, and is never checked
against EIOINTC_IRQS.

eiointc_set_irq() uses the value with __set_bit()/__clear_bit() on the
256-bit isr bitmap, eiointc_update_irq() then indexes sw_coremap[] and
the per-cpu coreisr/sw_coreisr bitmaps with it. Therefore a data value
>= 256 reads and writes memory past the end of those arrays, i.e. any
process holding a VM fd can corrupt kernel memory beyond the allocation
of loongarch_eiointc.

Reject MSI data that doesn't fit in the EIOINTC irq space. The DMSINTC
path is unaffected as it decodes the vector from the address and masks
it.

Cc: stable@vger.kernel.org
Fixes: 1928254c5c ("LoongArch: KVM: Add irqfd support")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://lore.kernel.org/all/20260531140921.1B1181F00893@smtp.kernel.org/
Reviewed-by: Tao Cui <cuitao@kylinos.cn>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:45:13 +08:00
Zeng Chi
27a9bfee3b LoongArch: KVM: Preserve memslot arch flags on KVM_MR_FLAGS_ONLY
kvm_arch_prepare_memory_region() computes new->arch.flags, i.e. whether
a memslot is KVM_MEM_HUGEPAGE_CAPABLE or KVM_MEM_HUGEPAGE_INCAPABLE,
only for KVM_MR_CREATE and KVM_MR_MOVE, and returns early for every
other change. But the generic code allocates a zeroed memslot for every
change and never copies old->arch, so after a KVM_MR_FLAGS_ONLY update,
e.g. toggling KVM_MEM_LOG_DIRTY_PAGES for live migration, the active
memslot has arch.flags == 0.

With both flags clear, fault_supports_huge_mapping() falls through to
the alignment check on the HVA range alone, which no longer verifies
that the GPA and HVA have the same offset within a PMD. A memslot that
was marked KVM_MEM_HUGEPAGE_INCAPABLE because of a GPA/HVA offset
mismatch can then be mapped with PMD entries on read faults, and since
kvm_map_page() aligns the gfn and the pfn independently, the guest ends
up accessing the wrong host pages, exactly the "d -> f, e -> g" case
described in the comment above the check.

Carry the arch flags over from the old memslot for KVM_MR_FLAGS_ONLY,
as the GPA, HVA and size are guaranteed to be unchanged for that case.

Cc: stable@vger.kernel.org
Fixes: 7ab6fb505b ("LoongArch: KVM: Optimization for memslot hugepage checking")
Tested-by: Tao Cui <cuitao@kylinos.cn>
Reviewed-by: Tao Cui <cuitao@kylinos.cn>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:45:13 +08:00
Bibo Mao
40bdbb4bfa LoongArch: KVM: Remove unused function kvm_arch_flush_remote_tlbs_memslot()
Function kvm_arch_flush_remote_tlbs_memslot() is not called any more, so
remove this API.

Reviewed-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:54 +08:00
Chaithanya Lagisetty
910132bc7d LoongArch: KVM: Fix resource leak in kvm_loongarch_env_init() error path
kvm_loongarch_env_init() allocates the per-CPU kvm_context (vmcs) and
kvm_loongarch_ops, registers the perf callbacks, and then registers
the IPI/EIOINTC/PCH-PIC/DMSINTC KVM devices. If any of those device
registrations fails, the function returned the error directly, leaving
everything acquired so far in place: vmcs and kvm_loongarch_ops are
never freed, the perf callbacks stay registered, and all previously
registered KVM device operations remain registered. kvm_loongarch_init()
propagates the errors without calling kvm_loongarch_env_exit(), so
nothing else cleans up either.

Unwind the error path in reverse order of registration, so that each
failure only undoes what had actually been set up. Use the same helpers
in kvm_loongarch_env_exit() to remove the device registrations during
normal teardown as well.

Cc: stable@vger.kernel.org
Fixes: c532de5a67 ("LoongArch: KVM: Add IPI device support")
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Chaithanya Lagisetty <nagachaithanya9911@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:54 +08:00
Chaithanya Lagisetty
4af2217703 LoongArch: KVM: Add unregister helpers for the KVM interrupt devices
The IPI/EIOINTC/PCH-PIC/DMSINTC KVM devices each have a helper that
registers their kvm_device_ops, but there is no counterpart to remove
them, so a caller that needs to undo a registration has to open-code
kvm_unregister_device_ops() with the matching device type.

Add kvm_loongarch_unregister_{ipi,eiointc,pch_pic,dmsintc}_device()
next to the existing register helpers. kvm_unregister_device_ops() is a
no-op when the corresponding device type is not currently registered.

No functional change, as there are no callers yet.

Cc: stable@vger.kernel.org
Suggested-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Chaithanya Lagisetty <nagachaithanya9911@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:53 +08:00
Chaithanya Lagisetty
f7a1064cce LoongArch: KVM: Free init resources if kvm_init() fails
kvm_loongarch_init() calls kvm_loongarch_env_init() to allocate the
per-CPU kvm_context (vmcs) and kvm_loongarch_ops and to register the
perf callbacks, and then calls kvm_init(). If kvm_init() fails its
result is returned directly, but since module_init() does not run the
module_exit() stuff on failure, so kvm_loongarch_env_exit() is never
called and those resources are leaked.

So call kvm_loongarch_env_exit() when kvm_init() fails, matching the
teardown-on-failure pattern used by riscv_kvm_init().

Cc: stable@vger.kernel.org
Fixes: 2bd6ac6872 ("LoongArch: KVM: Implement kvm module related interface")
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Chaithanya Lagisetty <nagachaithanya9911@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:53 +08:00
Tiezhu Yang
30419a0aa1 LoongArch: BPF: Fix off-by-one error for insn_is_cast_user()
In the LoongArch BPF JIT code, the branch offset represents the number
of instructions. An offset of 1 means the target of the "beq" is the
current PC plus 1 instruction (PC + 4 bytes). This matches the exact
same path as the sequential non-branch execution, the "or" instruction
is always executed for the cast_user JIT arm in build_insn().

If the pointer is not NULL, there is no side effect. But if the pointer
is NULL, it is incorrectly combined with the base address and turns into
a non-zero address, meaning a zero arena offset no longer casts to NULL.

Fix this by changing the branch offset from 1 to 2, which properly skips
the "or" instruction and jumps directly to the "move_reg" instruction if
the pointer is NULL, ensuring the destination register is safely cleared
to 0.

Cc: stable@vger.kernel.org
Fixes: 4fdb5dd8ae ("LoongArch: BPF: Implement bpf_addr_space_cast instruction")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:43 +08:00
Jérémy Jean
72ce4b2467 LoongArch: Avoid preempt count underflow without probe
LoongArch uses break 11 for the breakpoint placed after an instruction
that Kprobes executes out of line. Since userspace can issue the same
break instruction, do_bp() can reach kprobe_singlestep_handler() when
there is no current probe.

The handler actually returns false in this case, but it first calls
preempt_enable_no_resched(). The corresponding preempt_disable() is done
by kprobe_breakpoint_handler() on a real Kprobe hit, so it has not run
here. As a result, an ordinary userspace breakpoint (code 11) underflows
the current task's preempt count.

This also makes in_interrupt() return true until the task schedules. One
visible consequence is the socket cgroup attribution: cgroup_sk_alloc()
treats the allocation as interrupt context and assigns the socket to the
root cgroup. A socket opened from the SIGTRAP handler can then avoid a
BPF_CGROUP_INET_SOCK_CREATE policy attached to the task's own cgroup.

Return as soon as kprobe_running() reports no active probe.

The same check has appeared in [PATCH v10 2/4] of the original LoongArch
Kprobes series, but was dropped before the feature reached mainline.

Cc: stable@vger.kernel.org
Fixes: 6d4cc40fb5 ("LoongArch: Add kprobes support")
Link: https://lore.kernel.org/loongarch/1670575981-14389-3-git-send-email-yangtiezhu@loongson.cn/
Assisted-by: Codex:gpt-5
Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:43 +08:00
Wentao Guan
c3f2feace5 LoongArch: Do not save/restore percpu base register in rethook trampoline
The rethook trampoline saves $r21 ($u0), the percpu base, into its frame
at entry and restores it at exit. Inbetween rethook_trampoline_handler()
may schedule via preempt_enable_notrace().

If the task migrates to another CPU, the frame's $r21 holds the old
CPU's percpu base, and restoring it poisons $r21 on the new CPU. Until
the next user->kernel transition heals $r21, all this_cpu_*() accesses
(runqueues, RCU per-CPU data, timer tick programming, FPU ownership)
hit the wrong CPU's percpu area.

Under kretprobe-heavy preemptible load this can corrupt scheduler and
timer state: scheduling-while-atomic splats, wrong-CPU RCU warnings,
WARN_ON_ONCE(rq != this_rq()) in nohz_balance_exit_idle(), and CPUs
parking in the idle loop with the constant timer never re-armed (hard
lockup). Reproduces on a Loongson-3A6000 with kretprobes on VFS paths
plus heavy file churn (OS install / unsquashfs).

By convention $r21 always holds the current CPU's percpu base in kernel
mode: SAVE_SOME() at exception entry reloads it only when coming from
user mode, and RESTORE_SOME() restores it only when returning to user
mode; the context-switch path never writes it. Therefore the live $r21
at trampoline exit is already correct, and nothing inbetween can change
it legitimately (kernel C code cannot write a global register variable).
The same flaw existed even in the pre-rethook kretprobe trampoline since
v6.3; it was carried over when rethook replaced it. Drop both the save
and the restore here. Drop the restore is enough to solve the issue, and
drop the save is to keep the code tidy and no need to clear it.

Cc: stable@vger.kernel.org # v6.3+
Fixes: 3f55368600 ("LoongArch: Add kretprobes support")
Assisted-by: Kimi:Kimi-K3 # debug and root-cause analysis
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:43 +08:00
Anthony Iliopoulos
3e1b64bd8c LoongArch: Remove unused setup_profiling_timer() function
setup_profiling_timer() is not used by any code at this point. Since a
default weak implementation exists, there is no need to still keep this
arch-specific definition around. Remove it along with the now-redundant
profile header includes.

Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:43 +08:00
Hemanth Selam
20a9e97137 LoongArch: Fix typo "avaliable" in comment of vmlinux.lds.S
Correct "avaliable" to "available", reported by scripts/checkpatch.pl
using the misspelling list in scripts/spelling.txt. It only touches the
comments, no code changes.

Assisted-by: Cursor:claude-opus-5
Signed-off-by: Hemanth Selam <hemanth.selam@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:24 +08:00
Nathan Chancellor
63b6a48c95 LoongArch: Do not select HAVE_RUST when KASAN is enabled
After commit 2625480a1b ("hardening: Default randstruct off with rust
for better allmodconfig support"), which allows Rust to be enabled for
allmodconfig, ARCH=loongarch allmodconfig starts failing with:

  error: kernel-address sanitizer is not supported for this target

  error: aborting due to 1 previous error

  make[4]: *** [rust/Makefile:741: rust/core.o] Error 1

For the same reason as the commit 84a0f7caaf ("ARM: Do not select
HAVE_RUST when KASAN is enabled"), do not select HAVE_RUST when KASAN
is enabled until the loongarch64-unknown-none-softfloat target in rustc
supports KASAN.

Cc: stable@vger.kernel.org
Fixes: 90868ff9ca ("LoongArch: Enable initial Rust support")
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-09-04 21:44:23 +08:00
Linus Torvalds
7bb6284aa7 Arm:
* Add support for 'slot' based PMU events, paired with new UAPI that
   compels the user to select a specific PMU implementation
 
 * Lazy save/restore of vCPU state for pKVM, along with various fixes
   and cleanups to the management of vCPU state between the untrusted
   host and pKVM hypervisor
 
 * Disable traps of EL1 registers for nested hypervisors when FEAT_NV2p1
   is present, guaranteeing that EL2-specific register bits are stateful
   in the EL1 counterpart
 
 * Leverage FEAT_NV3 to avoid unnecessary ERET/TLBI traps when the scope
   of those instructions remains 'in host' (i.e. L1 kernel/userspace)
 
 * Pile of fixes for the management of the VNCR pseudo-TLB, such as
   under-invalidations and races with concurrent TLBIs on other vCPUs
 
 * Consolidate the non-protected and pKVM view of ICH_VTR_EL2 to a
   runtime-patched constant, allowing the same data to be shared with
   pKVM prior to dropping host privileges
 
 * Considerable pile of LLM-assisted fixes around the shop but mostly in
   the VGIC, our in-kernel generator of bugs (and sometimes interrupts)
 
 LoongArch:
 
 * Advertise already-supported capabilities.
 
 * Some bug fixes about timer and MMIO.
 
 * Some hardening about interrupt injection.
 
 * Replace kvm_err() with kvm_pr_unimpl().
 
 * Add FPU/LSX/LASX test cases for selftests.
 
 RISC-V:
 
 * Svadu/Zicfiss/Zicfilp FWFT support for Guest
 
 * Use try_cmpxchg for IMSIC MRIF RMW
 
 * More arch-specific tracepoints in KVM RISC-V
 
 * Eager page splitting when enabling dirty logging
 
 * Optimize hfence request handling for SMP Guests
 
 * Improve dirty log clearing by skipping zero bits in mask
 
 * Guard HFENCE range loops against overflow
 
 * CPU PM notifiers in KVM RISC-V for non-retentive idle states
 
 * Fix kernel-mode vector context save/restore for Guest
 
 s390:
 
 * Fixes for vfio-ap
 
 * Fixes for the gmap rework
 
 * Fixes for vsie
 
 * AI triggered fixes all over
 
 * diag9c tracing
 
 * code move preparation for the additional arm64 support
 
 * enable CONTEXT_ANALYSIS
 
 x86:
 
 * Perform spring cleaning on x86.{c,h} and asm/kvm_host.h, by adding regs.c
   (the kvm_cache_regs.h => regs.h is already applied) and msrs.{c,h}, and moving
   relevant code out of x86.c.
 
 * Split kvm_mmu in three parts, respectively to describe the format of page
   tables, walking the guest page tables and building the page tables.  Always
   use the same page table walker kvm->arch.gva_walk as the entry point to
   convert a guest's virtual address, where the previous code used two
   different kvm_mmu structs depending on whether the walk included nested
   EPT/NPT or not.  Make page fault vmexits reuse the permission checking
   machinery that is used for guest page faults.  This is both a cleanup
   and a baby step towards supporting XS/XU memory permissions.
 
 * Document some of the "fun" gotchas with the APIC base when creating IRQCHIPs
   on x86.
 
 * Remove a defunct masterclock update from kvm_xen_shared_info_init().  It
   could result in incorrect kvmclock due to triggering an unnecessary
   switch to/from masterclock mode.
 
 * Skip Xen runstate time updates if time has effectively gone backwards, so
   that the guest doesn't report 100% steal time for a very, very long time.
 
 * Drop KVM's runtime updates of the Xen PV timing CPUID leaf, as KVM was
   updating the wrong sub-leaf, and upstream KVM will soon provide all the
   information needed by userspace to populate the CPUID field itself.
 
 * Fix a bug where KVM would walk a newly created rmap without holding the rmap
   lock (or mmu_lock) during aging.
 
 * Fix a bug where aging TDP MMU SPTEs could clobber FROZEN SPTEs.
 
 * Fix a variety of #DB priority bugs.
 
 * Fix a class of races related to enabling Hyper-V emulation on a vCPU after
   the vCPU is visible to the rest of KVM.
 
 * Use static calls for nested virtualization ops.
 
 * Move more KVM-internal code out of x86's kvm_host.h.
 
 * Enumerate support for a variety of Zhaoxin instructions that don't require
   explicit virtualization.
 
 * Fix missing EFER validation bugs, including in the KVM_SET_SREGS* path.
 
 * Harden kvm_vcpu_map() against double-mapping and thus leaking references.
 
 * Misc fixes and cleanups, e.g. for largely benign syzkaller splats.
 
 x86 (Intel):
 
 * Zero a vCPU's entry in VMX's Posted Interrupt Descriptor table used for IPI
   virtualization when the vCPU is freed, to fix a use-after-free where hardware
   will write to a freed vCPU's PID.
 
 * Service local TLB flushes on a failed nested VM-Enter to fix a bug where KVM
   could miss a TLB on a future, successful VM-Enter with the same L2 VPID.
 
 * Cap the maximum value shoved into the VMX Preemption Timer to workaround an
   erratum that affects all existing Intel CPUs that support CPUID 0x15.
 
 * Fix VPID virtualization bugs where KVM would fail to flush hardware TLBs.
 
 * Harden the TDX "populate" ioctls against bad input, and to prepare
   for supporting in-place private<=>shared conversion.
 
 x86 (AMD):
 
 * Forcefully invalidate SNP VMSA pages if their backing guest_memfd page is
   zapped/invalidated, e.g. due to a PUNCH_HOLE in response to a Page-State
   Change request.
 
 * Remove a dying VM from the GA Log notifier list before the VM is actually
   destroyed, to fix a potential use-after-free.
 
 * While FOLL_WRITE was needed in the past to trigger CoW unsharing, nowadays
   FOLL_LONGTERM does that already even without FOLL_WRITE, and in fact,
   get_user_pages() actually disallows FOLL_WRITE together with FOLL_LONGTERM.
   So don't pass FOLL_WRITE when registering encrypted memory regions, i.e. when
   pinning SEV/SEV-ES guest memory, to fix a regression with file-backed memory
   introduced by KVM's (correct) usage of long-term pins.
 
   (This was reviewed by mm maintainers; for more information, see commit
   ee1a586dd1).
 
 * Allocate full pages for SEV/SEV-ES {DE,EN}CRYPT ops on SNP-enabled hosts to
   fix a data corruption issue due to the PSP driver assigning to-be-written
   pages to firmware (as required by the SNP specs).
 
 * Unconditionally intercept ICBEP so that KVM generates the correct guest RIP
   when handling an ICEBP-induced TASK_SWITCH #VMEXIT.
 
 * Harden the SNP "populate" ioctls against bad input, and to prepare
   for supporting in-place private<=>shared conversion.
 
 Generic:
 
 * Remove kvm_debugfs_dir if kvm_init() fails after creating KVM's debugfs.
 
 * Add a per-VM bitmap to track which vCPU IDs have been "claimed" but for
   which the vCPU isn't yet online, and use the bitmap to reject duplicate IDs
   before calling into arch code.  This allows arch code to consume vcpu_id
   without having to worry about cross-vCPU clobbering (at least s390 and x86
   have had related bugs).
 
 * Rework the so called "prepare" and "invalidate" guest_memfd hooks to prepare
   for in-place private<=>shared conversion, and clean up a few warts along the
   way.
 
 Selftests:
 
 * Automatically allocate a full page for L2 guest stacks on x86 instead of
   requiring test-specific L1 guest code to carve out a portion of the L1
   stack for L2 usage, and to ensure the L2 stack also adheres to the x86-64
   calling convention ABI.
 
 * Add a selftest to verify {Guest,Host}-Only behavior in x86's mediated PMU.
 
 * Clean up nested SVM's handling of GPRs on L2<=>L1 transitions, reuse the
   functionality for nested VMX, and drop the ucall hack that was fudging
   around the lack of GPR switching on nVMX.
 
 * Add a stress test to verify KVM doesn't clobber/drop #PF state, e.g. CR2,
   across save/restore, including when L2 is active.
 
 * Add a test to verify KVM_CREATE_VM accepts exactly what is reported by
   KVM_CAP_VM_TYPES.
 
 * Misc selftests fixes and cleanups
 
 * Fix several issues with seeding the pRNG, and rework the pRNG APIs to that
   the pRNG can be sanely used in host code, not just guest code.
 
 * Add an IRQ test to validate virtual IRQ deliverty for IRQs wired up via
   KVM_IRQFD + KVM_SET_GSI_ROUTING, with optional support for triggering IRQs
   via writes to an assigned VFIO device.
 
 * Add syscall wrappers to assert success on a variety of pthreads and CPU
   affinity APIs.
 
 * Set vCPU pthread affinity as early as possible to reduce contention issues
   that were surfaced by PREEMPT_LAZY, which result in runtimes of over a
   minute on large hosts, versus the expected ~5 seconds.
 
 * Rework the PMU counters test to run each testcase using a single VM with
   many vCPUs for each sub-testcase, instead of using a unique VM for each
   sub-testcase.  This cuts the runtime by ~20x.
 
 Miscellaneous:
 
 * MAINTAINERS updates for vfio-ap, guest_memfd, kvm-x86.  Mostly representing
   the status quo more accurately, but also... welcome David Hildenbrand
   as guest_memfd reviewer!
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmqMgosUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroP8bwf+ORImBMDM3QEmybZM3I+N2+xqSuHP
 QHttbmqGbsFK/RUeH96/X/+P9waqaz3uVeUQ6Qp2r0ryqwKtLt8YvIxKDp+M0vVJ
 n+iukk1xulBEc28aGdKHn9G4wayAwDA/9f7CvJ23hojaJfLScbF3OlFkDd7y5DpO
 x15Rtg9folYUjjop3LDML4N9/9Qmk4KRvVZ4ZVv6IB4uGJJ72fLd5dbBMyDk+BLl
 Lz9N1xVTXcnJXJmrjMB4/QNt/HiQJdun8LcokJZyykta7Xx6aY7OGZv+VmCeq47K
 e9Hk8mD4AyAdVbVvIntROSeBJOrlsgWJXAPHea6wEdRQnS3XVEBuZC0yDA==
 =rfLh
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM64:

   - Add support for 'slot' based PMU events, paired with new UAPI that
     compels the user to select a specific PMU implementation

   - Lazy save/restore of vCPU state for pKVM, along with various fixes
     and cleanups to the management of vCPU state between the untrusted
     host and pKVM hypervisor

   - Disable traps of EL1 registers for nested hypervisors when
     FEAT_NV2p1 is present, guaranteeing that EL2-specific register bits
     are stateful in the EL1 counterpart

   - Leverage FEAT_NV3 to avoid unnecessary ERET/TLBI traps when the
     scope of those instructions remains 'in host' (i.e. L1
     kernel/userspace)

   - Pile of fixes for the management of the VNCR pseudo-TLB, such as
     under-invalidations and races with concurrent TLBIs on other vCPUs

   - Consolidate the non-protected and pKVM view of ICH_VTR_EL2 to a
     runtime-patched constant, allowing the same data to be shared with
     pKVM prior to dropping host privileges

   - Considerable pile of LLM-assisted fixes around the shop but mostly
     in the VGIC, our in-kernel generator of bugs (and sometimes
     interrupts)

  LoongArch:

   - Advertise already-supported capabilities

   - Some bug fixes about timer and MMIO

   - Some hardening about interrupt injection

   - Replace kvm_err() with kvm_pr_unimpl()

   - Add FPU/LSX/LASX test cases for selftests

  RISC-V:

   - Svadu/Zicfiss/Zicfilp FWFT support for Guest

   - Use try_cmpxchg for IMSIC MRIF RMW

   - More arch-specific tracepoints in KVM RISC-V

   - Eager page splitting when enabling dirty logging

   - Optimize hfence request handling for SMP Guests

   - Improve dirty log clearing by skipping zero bits in mask

   - Guard HFENCE range loops against overflow

   - CPU PM notifiers in KVM RISC-V for non-retentive idle states

   - Fix kernel-mode vector context save/restore for Guest

  s390:

   - Fixes for vfio-ap

   - Fixes for the gmap rework

   - Fixes for vsie

   - AI triggered fixes all over

   - diag9c tracing

   - code move preparation for the additional arm64 support

   - enable CONTEXT_ANALYSIS

  x86:

   - Perform spring cleaning on x86.{c,h} and asm/kvm_host.h, by adding
     regs.c (the kvm_cache_regs.h => regs.h is already applied) and
     msrs.{c,h}, and moving relevant code out of x86.c

   - Split kvm_mmu in three parts, respectively to describe the format
     of page tables, walking the guest page tables and building the page
     tables. Always use the same page table walker kvm->arch.gva_walk as
     the entry point to convert a guest's virtual address, where the
     previous code used two different kvm_mmu structs depending on
     whether the walk included nested EPT/NPT or not. Make page fault
     vmexits reuse the permission checking machinery that is used for
     guest page faults. This is both a cleanup and a baby step towards
     supporting XS/XU memory permissions

   - Document some of the "fun" gotchas with the APIC base when creating
     IRQCHIPs on x86

   - Remove a defunct masterclock update from kvm_xen_shared_info_init().
     It could result in incorrect kvmclock due to triggering an
     unnecessary switch to/from masterclock mode

   - Skip Xen runstate time updates if time has effectively gone
     backwards, so that the guest doesn't report 100% steal time for
     a very, very long time

   - Drop KVM's runtime updates of the Xen PV timing CPUID leaf, as KVM
     was updating the wrong sub-leaf, and upstream KVM will soon provide
     all the information needed by userspace to populate the CPUID field
     itself

   - Fix a bug where KVM would walk a newly created rmap without holding
     the rmap lock (or mmu_lock) during aging

   - Fix a bug where aging TDP MMU SPTEs could clobber FROZEN SPTEs

   - Fix a variety of #DB priority bugs

   - Fix a class of races related to enabling Hyper-V emulation on a
     vCPU after the vCPU is visible to the rest of KVM

   - Use static calls for nested virtualization ops

   - Move more KVM-internal code out of x86's kvm_host.h

   - Enumerate support for a variety of Zhaoxin instructions that don't
     require explicit virtualization

   - Fix missing EFER validation bugs, including in the KVM_SET_SREGS*
     path

   - Harden kvm_vcpu_map() against double-mapping and thus leaking
     references

   - Misc fixes and cleanups, e.g. for largely benign syzkaller splats

  x86 (Intel):

   - Zero a vCPU's entry in VMX's Posted Interrupt Descriptor table used
     for IPI virtualization when the vCPU is freed, to fix a
     use-after-free where hardware will write to a freed vCPU's PID

   - Service local TLB flushes on a failed nested VM-Enter to fix a bug
     where KVM could miss a TLB on a future, successful VM-Enter with
     the same L2 VPID

   - Cap the maximum value shoved into the VMX Preemption Timer to
     workaround an erratum that affects all existing Intel CPUs that
     support CPUID 0x15

   - Fix VPID virtualization bugs where KVM would fail to flush hardware
     TLBs

   - Harden the TDX "populate" ioctls against bad input, and to prepare
     for supporting in-place private<=>shared conversion

  x86 (AMD):

   - Forcefully invalidate SNP VMSA pages if their backing guest_memfd
     page is zapped/invalidated, e.g. due to a PUNCH_HOLE in response to
     a Page-State Change request

   - Remove a dying VM from the GA Log notifier list before the VM is
     actually destroyed, to fix a potential use-after-free

   - While FOLL_WRITE was needed in the past to trigger CoW unsharing,
     nowadays FOLL_LONGTERM does that already even without FOLL_WRITE,
     and in fact, get_user_pages() actually disallows FOLL_WRITE
     together with FOLL_LONGTERM. So don't pass FOLL_WRITE when
     registering encrypted memory regions, i.e. when pinning SEV/SEV-ES
     guest memory, to fix a regression with file-backed memory
     introduced by KVM's (correct) usage of long-term pins

     (This was reviewed by mm maintainers; for more information, see
     commit ee1a586dd1 "KVM: SEV: Drop FOLL_WRITE for encrypted region
     registration")

   - Allocate full pages for SEV/SEV-ES {DE,EN}CRYPT ops on SNP-enabled
     hosts to fix a data corruption issue due to the PSP driver
     assigning to-be-written pages to firmware (as required by the SNP
     specs)

   - Unconditionally intercept ICBEP so that KVM generates the correct
     guest RIP when handling an ICEBP-induced TASK_SWITCH #VMEXIT

   - Harden the SNP "populate" ioctls against bad input, and to prepare
     for supporting in-place private<=>shared conversion

  Generic:

   - Remove kvm_debugfs_dir if kvm_init() fails after creating KVM's
     debugfs

   - Add a per-VM bitmap to track which vCPU IDs have been "claimed" but
     for which the vCPU isn't yet online, and use the bitmap to reject
     duplicate IDs before calling into arch code. This allows arch code
     to consume vcpu_id without having to worry about cross-vCPU
     clobbering (at least s390 and x86 have had related bugs)

   - Rework the so called "prepare" and "invalidate" guest_memfd hooks
     to prepare for in-place private<=>shared conversion, and clean up a
     few warts along the way

  Selftests:

   - Automatically allocate a full page for L2 guest stacks on x86
     instead of requiring test-specific L1 guest code to carve out a
     portion of the L1 stack for L2 usage, and to ensure the L2 stack
     also adheres to the x86-64 calling convention ABI

   - Add a selftest to verify {Guest,Host}-Only behavior in x86's
     mediated PMU

   - Clean up nested SVM's handling of GPRs on L2<=>L1 transitions,
     reuse the functionality for nested VMX, and drop the ucall hack
     that was fudging around the lack of GPR switching on nVMX

   - Add a stress test to verify KVM doesn't clobber/drop #PF state,
     e.g. CR2, across save/restore, including when L2 is active

   - Add a test to verify KVM_CREATE_VM accepts exactly what is reported
     by KVM_CAP_VM_TYPES

   - Misc selftests fixes and cleanups

   - Fix several issues with seeding the pRNG, and rework the pRNG APIs
     to that the pRNG can be sanely used in host code, not just guest
     code

   - Add an IRQ test to validate virtual IRQ deliverty for IRQs wired up
     via KVM_IRQFD + KVM_SET_GSI_ROUTING, with optional support for
     triggering IRQs via writes to an assigned VFIO device

   - Add syscall wrappers to assert success on a variety of pthreads and
     CPU affinity APIs

   - Set vCPU pthread affinity as early as possible to reduce contention
     issues that were surfaced by PREEMPT_LAZY, which result in runtimes
     of over a minute on large hosts, versus the expected ~5 seconds

   - Rework the PMU counters test to run each testcase using a single VM
     with many vCPUs for each sub-testcase, instead of using a unique VM
     for each sub-testcase. This cuts the runtime by ~20x

  Miscellaneous:

   - MAINTAINERS updates for vfio-ap, guest_memfd, kvm-x86. Mostly
     representing the status quo more accurately, but also... welcome
     David Hildenbrand as guest_memfd reviewer!"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (413 commits)
  KVM: arm64: Validate GICv5 timer PPIs before claiming ownership
  KVM: arm64: vgic: Reject out-of-range GICv5 PPI IDs
  KVM: arm64: vgic: Prevent speculative SPI array underflow
  KVM: arm64: vgic: Free gic_kvm_info on initialization failure
  KVM: arm64: Avoid mismatched accesses to 'struct kvm_nvhe_init_params'
  s390/vfio-ap: Fix NULL deref in status_show() during queue probe
  s390/vfio-ap: Fix hot-unplug skipped when last AP adapter or domain removed
  s390/vfio-ap: fix potential use of uninitialized apm_filtered bitmap
  s390/vfio-ap: Fix control domain removal in vfio_ap_mdev_cfg_remove
  s390/vfio-ap: Fix required lock not held during update of ap_matrix_mdev object
  s390/vfio-ap: Fix missing lock required to access list of ap_matrix_mdev objects
  s390/vfio-ap: Fix dereference matrix_mdev->kvm without checking for NULL
  s390/vfio-ap: Fix stale do_remove flag across iterations in vfio_ap_mdev_cfg_remove
  RISC-V: KVM: fix vcpu vector context handling for kernel-mode vector
  riscv: vector: allow non-preemptible kernel-mode vector with IRQs off
  riscv: vector: refactor riscv_v_start_kernel_context
  KVM: s390: gmap: Make prefix handling optional
  KVM: s390: gmap: Make CMMA optional
  KVM: s390: gmap: Make storage keys optional
  KVM: s390: Prepare gmap for a second KVM implementation
  ...
2026-08-25 11:48:04 -07:00
Linus Torvalds
ed3b875bea mm.git review status for mm-hotfixes-stable..mm-stable
Everything:
 
 Total patches:       501
 Reviews/patch:       1.66
 Reviewed rate:       70%
 
 Excluding DAMON:
 
 Total patches:       356
 Reviews/patch:       2.26
 Reviewed rate:       90%
 
 Excluding DAMON and selftests:
 
 Total patches:       329
 Reviews/patch:       2.31
 Reviewed rate:       92%
 
 Excluding DAMON, selftests and maple_tree:
 
 Total patches:       328
 Reviews/patch:       2.31
 Reviewed rate:       92%
 
 Summary of patch series in this merge:
 
 - The 2 patch series "mm: drop "sub" prefix from various places" from
   Dev Jain implements some page->folio conversion and a naming cleanup.
 
 - The 2 patch series "mm/kasan: remove redundant initialization for
   kasan_flag_write_only" from Igor Putko provides some KASAN cleanup work.
 
 - The 2 patch series "mm/filemap: reduce unnecessary xarray lookups"
   from Chi Zhiling provides a small speedup in the pagecaache read code.
 
 - The 4 patch series "mm/percpu: Fix possible NOFS/NOIO reclaim
   recursion" from Kaitao Cheng improves a few things in the vmalloc code -
   mainly the avoidance of GFP_KERNEL allocations when the caller asked for
   GFP_NOFS or GFP_NOIO.
 
 - The 3 patch series "mm/kmemleak: avoid soft lockup when scanning task
   stacks" from Breno Leitao avoids a soft lockup watchdog trigger from the
   kmemleak scanning code in extreme situations.
 
 - The 6 patch series "mm/page_owner: misc cleanups" from Ye Liu is a
   collection of unrelated cleanups to the page_owner code.  For some
   reason lots of people have been working on the page_owner code this
   cycle.
 
 - The 4 patch series "mm: convert to walk_page_range_vma() to eliminate
   find_vma()" from Kefeng Wang simplifies and accelerates the page walking
   library function.
 
 - The 3 patch series "mm/migrate: preparatory cleanups for batch copy
   and offload" from Shivank Garg implements cleanups in the migration
   code.
 
 - The 4 patch series "mm/page_owner: add per-fd filter infrastructure
   for print_mode and NUMA filtering" from Zhen Ni provides per-fd
   filtering to page_owner in order to reduce the sometimes vast amount of
   output it can produce.
 
 - The 19 patch series "mm: Refactor bootmem gigantic hugepage
   allocation" from Muchun Song is a "set of fixes and preparatory cleanups
   around bootmem HugeTLB handling, sparse initialization ordering, and
   related vmemmap setup".
 
 - The 4 patch series "mm/zsmalloc: reduce lock contention in zs_free()"
   from Wenchao Hao reduces lock contention in zs_free(), which dominates
   the unmap path under memory pressure on Android (LMK kills) and on x86
   servers running zswap-heavy workloads.  Up to 1.83x improvement in
   microbenchmarking.
 
 - The 2 patch series "move alloc_tag.c file under mm/" from Suren
   Baghdasaryan does that.
 
 - The 6 patch series "samples/damon: handle damon_{start,stop}()
   failures" from SJ Park fixes improper handling of damon_start(),
   damon_stop(), and damon_call() failures across DAMON sample modules to
   prevent potential memory leaks, operation disruptions and use-after-free
   bugs.
 
 - The 11 patch series "mm/damon/sysfs: kobject_del() directories that
   users can create/remove" from SJ Park resolves an issue where delayed
   sysfs directory removal under CONFIG_DEBUG_KOBJECT_RELEASE causes
   creation failures due to duplicate directory names by adding missing
   kobject_del() calls before creating new directories.
 
 - The 3 patch series "mm: cleanup clear_not_present_full_ptes()" from
   David Hildenbrand cleans up the core pte handling code.
 
 - The 3 patch series "selftests/damon: misc fixes for test bugs" from
   Kunwu Chan fixes several bugs in the DAMON selftests.
 
 - The 2 patch series "selftests/damon: fix memcg_path staging handling"
   from Cheng Nie fixes a bug in _damon_sysfs.py for damos_filter
   memcg_path setup, and adds a test case for it in sysfs.py.
 
 - The 2 patch series "selftests/damon: test kdamond refresh_ms" from
   Ruslan Valiyev introduces selftest coverage for DAMON's refresh_ms sysfs
   feature by updating the test control module and verifying that scheme
   stats update automatically without manual intervention.
 
 - The 5 patch series "mm/damon: five misc fixups" from Akinobu Mita
   contains miscellaneous DAMON fixups.
 
 - The 2 patch series "mm/damon/core: detect internal variation above
   max_nr_regions/2" from Jiayuan Chen fixes DAMON's region splitting
   behavior when region counts exceed half the maximum budget by
   dynamically scaling down the split fraction as the limit approaches,
   preventing large regions from staying un-split, and adds corresponding
   KUnit test coverage.
 
 - The 6 patch series "mm: preparatory patches for PMD level swap
   entries" from Usama Arif refactors and cleans up PMD softleaf helpers,
   call sites, and architecture flags to lay the groundwork for a follow-up
   series that introduces PMD page table swap entries.
 
 - The 11 patch series "mm/damon: update, optimize, and clean up doc,
   tests, and code" from SJ Park updates DAMON design and ABI
   documentation, expands unit and selftest coverage, optimizes
   damon_commit_target_regions(), and cleans up recently added sysfs
   interface code for better readability.
 
 - The 2 patch series "mm/vmpressure: reduce CPU, memory and code
   overhead on cgroup v2" from Usama Arif optimizes vmpressure() by
   skipping unnecessary work on cgroup v2 for userspace event notifications
   and refactors v1-only eventfd handling into mm/memcontrol-v1.c to reduce
   memory overhead and code complexity.
 
 - The 10 patch series "selftests/mm: refactor pkey helpers and fix mmap
   error handling" from Hongfu Li refactors pkeys shared tracing and
   assertion helpers into a common file, unifies protection key selftests
   to use consistent diagnostic logging and assertions, and enforces
   standardized MAP_FAILED return checks for mmap() calls across the tests.
 
 - The 18 patch series "mm/damon: optimize out nr_accesses_bp" from SJ
   Park replaces the error-prone, continuously updated nr_accesses_bp field
   in damon_region with an on-demand moving sum function
   (damon_nr_accesses_mvsum()), reducing structure memory overhead and
   avoiding state corruption bugs.
 
 - The 6 patch series "Open HugeTLB allocation routine for more generic
   use" from Ackerley Tng decouples HugeTLB folio allocation from VMA
   dependencies by introducing hugetlb_alloc_folio(), enabling subsystems
   like guest_memfd to allocate HugeTLB folios without standard VMA
   reservations or pseudo-VMAs.
 
 - The 3 patch series "mm/damon: provide pseudo moving sum probe_hits"
   from SJ Park integrates DAMON's probe_hits attribute counter into the
   pseudo moving sum infrastructure, enabling real-time, online monitoring
   without waiting for full aggregation intervals.
 
 - The 18 patch series "mm: Some cleanups for page allocator APIs" from
   Brendan Jackman simplifies and refactors the page allocator entry points
   and flags by unifying allocation paths, adding internal alloc_flags
   arguments, and eliminating redundant __ prefixed alloc_pages variants.
 
 - The 5 patch series "Fix incorrect access of hugetlb pte entries" from
   Dev Jain enforces the consistent use of huge_ptep_get() instead of
   ptep_get() for HugeTLB entries and fixes an unaligned address issue in
   arm64's huge_ptep_get() implementation.
 
 - The 8 patch series "mm/damon: validate all parameters in the core"
   from SJ Park consolidates parameter validation into the DAMON core
   specifically within damon_start() and damon_commit_ctx() to centralize
   error checking, eliminate caller-side redundant checks and to improve
   maintenance efficiency.
 
 - The 3 patch series "tools/mm/page_owner_sort: fix filtering and
   cleanup issues" from Yichong Chen renames is_need() to filter_record()
   for clearer return semantics, fixes per-record allocation memory leaks
   and bounds output copies in search_pattern() to address an existing
   buffer issue.
 
 - The 4 patch series "memcg: bail out reclaim when memcg is dying" from
   Jiayuan Chen mitigates a system-wide stall which occurs when a cgroup is
   removed while one of its memory control files is doing synchronous
   reclaim.
 
 - The 5 patch series "mm/memory-failure: add panic option for
   unrecoverable pages" from Breno Leitao introduces an opt-in
   vm.panic_on_unrecoverable_memory_failure sysctl that immediately panics
   the kernel on unrecoverable memory errors in kernel-owned pages to
   preserve error context and prevent delayed, silent data corruption.
 
 - The 11 patch series "mm/damon: refactor damon_{start,stop,commit}()
   for simple error handling" from SJ Park refactors the DAMON core API
   functions to guarantee that all contexts are fully stopped when
   damon_start(), damon_stop(), or damon_commit() fail, eliminating the
   need for complex and error-prone caller-side cleanup code.
 
 - The 5 patch series "Keep tail page private zero at free and folio
   split" from Zi Yan adds checks to ensure tail_page->private is zero when
   freeing compound or high-order pages and when promoting tail pages
   during large folio splits.  By validating these fields at free and split
   time, it allows the removal of redundant private field clearing inside
   prep_compound_tail().
 
 - The 4 patch series "mm: drop redundant lru_add_drain in anon folio
   reuse paths" from Barry Song eliminates redundant lru_add_drain() calls
   in wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock
   contention and system overhead.
 
   By validating folio refcounts against the LRU cache before draining
   and removing unnecessary drains in the swap path, it achieves up to a
   30.5% reduction in drain calls during heavy swap workloads.
 
 - The 3 patch series "mm: clean up folio LRU and swap declarations" from
   Jianyue Wu reorganizes folio LRU and swap code by relocating
   page-cluster state to mm/swap_state.c, renaming mm/swap.c to mm/folio.c,
   and moving MM-internal reclaim declarations into mm/internal.h.
 
 - The 15 patch series "userfaultfd: working set tracking for VM guest
   memory" from Kiryl Shutsemau adds userfaultfd support for tracking the
   working set of VM guest memory, so a VMM can identify hot pages and
   reclaim cold ones to tiered or remote storage.
 
 - The 10 patch series "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part
   2)" from David Hildenbrand removes the remaining pieces of
   CONFIG_HAVE_BOOTMEM_INFO_NODE, performing some smaller cleanups around
   freeing of reserved vmemmap pages on the way.
 
 - The 7 patch series "mm/damon: update probe hits for runtime parameter
   commits" from SJ Park ensures that DAMON's probe_hits attribute counter
   is properly updated when monitoring intervals are changed at runtime,
   matching the behavior of nr_accesses.  To achieve this, it refactors and
   renames existing helper functions for shared use, applies the updates to
   probe_hits, and handles edge cases in damon_probe_hits_mvsum() to
   maintain measurement accuracy.
 
 - The 3 patch series "KSM: performance optimizations for rmap_walk_ksm"
   from xu xin resolves a severe KSM reverse-mapping performance bottleneck
   where thousands of split VMAs sharing a single anon_vma cause extended
   lock contention.  By adding an interval-filtering check during the rmap
   walk, it reduces worst-case anon_vma lock hold times from over 500ms
   down to under 2ms, preventing application freezes and latency spikes
   under memory pressure.
 
 - The 3 patch series "mm: split a couple of headers from internal.h"
   from Mike Rapoport splits declarations related to mm_init, memblock,
   vmalloc and sparse into new headers.
 
 - The 2 patch series "KSM: use linear_page_index in collect_procs_ksm()"
   from xu xin applies the interval tree optimization from rmap_walk_ksm()
   to collect_procs_ksm() to avoid iterating over non-matching VMAs during
   KSM memory error handling.  It hoists loop-invariant address
   initialization and restricts the anon_vma_interval_tree_foreach walk to
   a targeted page offset range, reducing redundant checks and improving
   lookup efficiency.
 
 - The 3 patch series "selftests/mm: avoid false failures in hugetlb and
   KSM tests" from Sayali Patil fixes issues in the hugetlb and KSM MM
   selftest categories that can report failures when the prerequisites for
   the tests are not satisfied.
 
 - The 19 patch series "mm/damon: introduce data attributes only
   monitoring" from SJ Park introduces attribute-weighted region management
   in DAMON, allowing users to prioritize specific data attributes (such as
   page sizes or cgroups) over or instead of access monitoring.
 
   By assigning weights to attribute probes, DAMON can completely disable
   access tracking and adjust monitoring regions based on weighted
   probe-hit counters to optimize monitoring quality for attribute-focused
   workloads.
 
 - The 8 patch series "mm/hmm: Add mmap lock-drop support for
   userfaultfd-backed mappings" from Stanislav Kinsburskii extends
   hmm_range_fault() to support userfaultfd-backed regions by allowing the
   mmap lock to be dropped during fault handling via a new
   hmm_range_fault_locked() helper.
 
   By accepting a locked pointer and signaling retry status when lock
   release occurs, it enables page fault resolution in userfaultfd regions
   while preserving backward compatibility for existing callers.
 
 - The 33 patch series "mm: make VMA page offset handling more
   consistent" from Lorenzo Stoakes cleans up and standardizes how
   vma->vm_pgoff is accessed and manipulated across file-backed and
   anonymous mappings in the kernel.
 
   It introduces dedicated helper functions such as vma_start_pgoff(),
   vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while renaming
   rmap interval tree helpers to better reflect their functionality.
 
   These changes establish a cleaner foundation for future work that will
   unify virtual page offset indexing for all anonymous and CoW'd folios.
 
 - The 3 patch series "mm: handle device-private PMDs in walk callbacks"
   from Usama Arif addresses kernel panics and state corruption caused by
   MM walk callbacks reaching non-present device-private PMD swap entries
   created during HMM migrations.
 
   It ensures that functions which acquire pmd_trans_huge_lock() properly
   recognize device-private PMDs instead of assuming a present THP or a
   standard migration entry.
 
 - The 5 patch series "mm/rmap: Refactor try_to_unmap_one" from Dev Jain
   refactors try_to_unmap_one by modularizing Hugetlb, anonymous-lazyfree,
   and anonymous-swapbacked logic into dedicated functions, laying the
   structural groundwork for batched anonymous large folio unmapping.
 
 - The 4 patch series "Docs/ABI/damon: sysfs ABI document fixes and
   additions" from Song Hu fixes typos and fills in missing entries in the
   DAMON sysfs ABI document.
 
 - The 10 patch series "dax/kmem: atomic whole-device hotplug via sysfs"
   from Gregory Price introduces an atomic sysfs state attribute and
   supporting DAX/MM infrastructure to prevent userland races when
   offlining and removing entire memory regions.
 
   By adding an unplugged state alongside standard online modes, it
   enables whole-device atomic hotplug control while preserving backward
   compatibility.
 
 - The 13 patch series "mm: convert more vm_flags_t users to vma_flags_t"
   from Lorenzo Stoakes continues transitioning the kernel from the
   deprecated vm_flags_t type to vma_flags_t across core memory management
   infrastructure.
 
   It replaces legacy type usage in core functions such as do_mmap(),
   unmapped area allocation, mm->def_vma_flags, and VMA operations like
   mlock, mprotect, and mremap.
 
 - The 2 patch series "Two small patches to clean up mm/mm_slot.h" from
   xu xin refactors mm_slot.h by introducing mm_slot_remove() to unify
   duplicate slot deletion sequences in khugepaged and KSM.  It also adds
   code documentation explaining why mm_slot_lookup and mm_slot_insert must
   remain as preprocessor macros rather than static inline functions.
 
 - The 10 patch series "mm/damon/core: hide core-private struct fields"
   from SJ Park cleans up DAMON core structures by consistently marking
   internal-only fields with private: comment tags to prevent improper
   direct access from outer layers.
 
   It enforces encapsulation across core structures including
   damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to
   interact through approved access APIs instead of exposing raw struct
   members.
 
 - The 6 patch series "mm/damon: unurgent fixes for infinite loop, NULL
   de-ref and races" from SJ Park addresses potential infinite loops, NULL
   dereferences, and race conditions identified in DAMON.
 
   It fixes an infinite loop triggered by extreme user configurations, a
   NULL pointer dereference within unit tests and minor monitoring
   accuracy degradation caused by subtle runtime races.
 
 - The 2 patch series "mm/page_alloc: fixes for free_pages_nolock() on
   RT/UP" from Brendan Jackman fixes an NMI safety flaw in
   __free_frozen_pages() where freeing pages on non-SMP or PREEMPT_RT
   kernels can bypass can_spin_trylock() checks via non-PCP or isolated
   migration paths.
 
   It also resolves potential kernel crashes and privilege escalation
   risks triggered when BPF tracing runs in NMI context alongside memory
   hotplug or large allocation frees.
 
 - The 4 patch series "mm/page_alloc: couple of followups for recent
   cleanups" from Brendan Jackman cleans up and updates page allocator
   nomenclature, documentation, and debug assertions.
 
   It aligns internal FPI_ flags with the public "nolock" naming
   convention, removes outdated internal implementation details from
   high-level page allocator comments, and eliminates obsolete VM_BUG_ON()
   assertions in allocation paths.
 
 - The 3 patch series "mm/mseal: further cleanups" from Lorenzo Stoakes
   refactors and simplifies the mseal implementation by clarifying API
   boundaries and removing unnecessary code complexity.
 
   It replaces generic do_mseal() usage outside the syscall with a
   dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO, eliminates
   mm_struct parameters to enforce that sealing applies only to
   current->mm, and streamlines overall logic and comments with no
   functional changes intended.
 
 - The 4 patch series "mm/vmscan: fix swappiness=max and clean up
   per-node proactive reclaim" from Ridong Chen resolves reclaim behavior
   bugs and cleans up function parameters across memory reclaim paths.
 
   It fixes swappiness=max in both standard reclaim and MGLRU so
   unswappable anonymous memory no longer falls back to evicting page
   cache, ensures reclaim_store() returns accurate error codes instead of
   collapsing all failures into -EAGAIN, and removes the obsolete gfp_mask
   parameter from __node_reclaim().
 
 - The 6 patch series "mm: mincore: misc cleanups" from Kefeng Wang
   cleans up and simplifies the mincore code.  Most importantly, it removes
   the historical special behavior that always reports VM_PFNMAP pages as
   non-resident.
 
 - The 2 patch series "mm/huge_memory: drop dead split helper variants"
   from Kiryl Shutsemau implements two trivial cleanups in the folio split
   API.
 
 - The 7 patch series "mm/damon: fix uninitialized DAMOS field and kunit
   exec expectation bugs" from SJ Park resolves minor operational and
   testing bugs in DAMON identified by Sashiko.  It initializes the
   damos->last_applied field to prevent occasional efficiency degradation
   and fixes invalid memory accesses in DAMON KUnit tests during test
   failure handling.
 
 - The 3 patch series "cleanup for stable_page_flags()" from Jinjiang Tu
   cleans up and refactors stable_page_flags() used by /proc/kpageflags
   without altering functionality.
 
   It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag
   bits, converts folio-specific flag checks to standard folio_test_*()
   helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling.
 
 - The 3 patch series "Batch unmap of uffd-wp file folios" from Dev Jain
   extends batched folio unmapping support to file folios within
   userfaultfd write-protect (uffd-wp) VMAs by adding batching capabilities
   to pte_install_uffd_wp_if_needed().
 
   This removes special-case restrictions on uffd-wp VMAs in
   try_to_unmap_one(), significantly simplifying the function's control
   flow and complexity.
 
 - The 3 patch series "mm/early_ioremap: clarify and clean up
   early_ioremap_reset()" from Sang-Heon Jeon clarifies and cleans up the
   architecture-specific usage of __late_set_fixmap() and
   __late_clear_fixmap() after early_ioremap_reset().
 
   It adds explicit documentation regarding when early_ioremap_reset()
   must be called and removes redundant macro definitions and reset calls
   in the RISC-V and ARM64 architectures.
 
 - The 4 patch series "mm: fix reclaim storms in defrag_mode" from
   Johannes Weiner addresses severe performance regressions, swap storms,
   and spurious OOMs caused by vm.defrag_mode=1 under high memory pressure
   in Meta production.
 
   It updates the page allocator slowpath so non-movable allocation
   requests actively trigger direct reclaim and direct compaction at
   pageblock_order scale, allowing them to claim whole pageblocks rather
   than spinning unproductively.
 
 - The 2 patch series "zram: lockmap tweaks" from Sebastian Siewior
   optimizes and fixes lockdep tracking for zram devices by consolidating
   per-entry lockmaps and isolating lock classes across multiple instances.
 
   It reduces memory overhead by replacing per-entry lockdep_map instances
   with a single map per struct zram, and assigns a dynamic lock_class_key
   to each instance to prevent false deadlock reports when different zram
   devices are backed by distinct filesystems.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaoUJbQAKCRDdBJ7gKXxA
 jqrzAP9WoPU0hiK4qS/kSjhtoZxhjpS5eLSUCy/utKuEvZbfGgEAu1zA+LH+X9Tm
 THK5ex4iUZxiFbXpWfLMxE/Q9PmQYQ8=
 =QTyb
 -----END PGP SIGNATURE-----

Merge tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "mm: drop "sub" prefix from various places" (Dev Jain)

   page->folio conversion and a naming cleanup

 - "mm/kasan: remove redundant initialization for kasan_flag_write_only"
   (Igor Putko)

   KASAN cleanup work

 - "mm/filemap: reduce unnecessary xarray lookups" (Chi Zhiling)

   Small speedup in the pagecaache read code

 - "mm/percpu: Fix possible NOFS/NOIO reclaim recursion" (Kaitao Cheng)

   Improve the vmalloc code - mainly the avoidance of GFP_KERNEL
   allocations when the caller asked for GFP_NOFS or GFP_NOIO

 - "mm/kmemleak: avoid soft lockup when scanning task stacks" (Breno
   Leitao)

   Avoid a soft lockup watchdog trigger from the kmemleak scanning code
   in extreme situations

 - "mm/page_owner: misc cleanups" (Ye Liu)

   Cleanups to the page_owner code. For some reason lots of people have
   been working on the page_owner code this cycle.

 - "mm: convert to walk_page_range_vma() to eliminate find_vma()"
   (Kefeng Wang)

   Simplify and accelerate the page walking library function

 - "mm/migrate: preparatory cleanups for batch copy and offload"
   (Shivank Garg)

   Cleanups in the migration code

 - "mm/page_owner: add per-fd filter infrastructure for print_mode and
   NUMA filtering" (Zhen Ni)

   Per-fd filtering to page_owner in order to reduce the sometimes vast
   amount of output it can produce

 - "mm: Refactor bootmem gigantic hugepage allocation" (Muchun Song)

   Fixes and preparatory cleanups around bootmem HugeTLB handling,
   sparse initialization ordering, and related vmemmap setup

 - "mm/zsmalloc: reduce lock contention in zs_free()" (Wenchao Hao)

   Reduce lock contention in zs_free(), which dominates the unmap path
   under memory pressure on Android (LMK kills) and on x86 servers
   running zswap-heavy workloads.

   Up to 1.83x improvement in microbenchmarking.

 - "move alloc_tag.c file under mm/" (Suren Baghdasaryan)

 - "samples/damon: handle damon_{start,stop}() failures" (SJ Park)

   Fix improper handling of damon_start(), damon_stop(), and
   damon_call() failures across DAMON sample modules to prevent
   potential memory leaks, operation disruptions and use-after-free
   bugs

 - "mm/damon/sysfs: kobject_del() directories that users can
   create/remove" (SJ Park)

   Fix delayed sysfs directory removal under DEBUG_KOBJECT_RELEASE
   causeing creation failures due to duplicate directory names by adding
   missing kobject_del() calls before creating new directories

 - "mm: cleanup clear_not_present_full_ptes()" (David Hildenbrand)

   Clean up the core pte handling code

 - "selftests/damon: misc fixes for test bugs" (Kunwu Chan)

   Fix several bugs in the DAMON selftests

 - "selftests/damon: fix memcg_path staging handling" (Cheng Nie)

   Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and
   add a test case for it in sysfs.py.

 - "selftests/damon: test kdamond refresh_ms" (Ruslan Valiyev)

   Selftest coverage for DAMON's refresh_ms sysfs feature by updating
   the test control module and verifying that scheme stats update
   automatically without manual intervention

 - "mm/damon: five misc fixups" (Akinobu Mita)

   Miscellaneous DAMON fixups.

 - "mm/damon/core: detect internal variation above max_nr_regions/2"
   (Jiayuan Chen)

   Fix DAMON's region splitting behavior when region counts exceed half
   the maximum budget by dynamically scaling down the split fraction as
   the limit approaches, preventing large regions from staying un-split,
   and add corresponding KUnit test coverage

 - "mm: preparatory patches for PMD level swap entries" (Usama Arif)

   Refactor and clean up PMD softleaf helpers, call sites, and
   architecture flags to lay the groundwork for a follow-up series that
   introduces PMD page table swap entries

 - "mm/damon: update, optimize, and clean up doc, tests, and code" (SJ
   Park)

   Update DAMON design and ABI documentation, expands unit and selftest
   coverage, optimize damon_commit_target_regions(), and clean up
   recently added sysfs interface code for better readability

 - "mm/vmpressure: reduce CPU, memory and code overhead on cgroup v2"
   (Usama Arif)

   Optimize vmpressure() by skipping unnecessary work on cgroup v2 for
   userspace event notifications and refactor v1-only eventfd handling
   into mm/memcontrol-v1.c to reduce memory overhead and code complexity

 - "selftests/mm: refactor pkey helpers and fix mmap error handling"
   (Hongfu Li)

   Refactor pkeys shared tracing and assertion helpers into a common
   file, unify protection key selftests to use consistent diagnostic
   logging and assertions, and enforce standardized MAP_FAILED return
   checks for mmap() calls across the tests

 - "mm/damon: optimize out nr_accesses_bp" (SJ Park)

   Replace the error-prone, continuously updated nr_accesses_bp field in
   damon_region with an on-demand moving sum function, reducing
   structure memory overhead and avoiding state corruption bugs

 - "Open HugeTLB allocation routine for more generic use" (Ackerley Tng)

   Decouple HugeTLB folio allocation from VMA dependencies by
   introducing hugetlb_alloc_folio(), enabling subsystems like
   guest_memfd to allocate HugeTLB folios without standard VMA
   reservations or pseudo-VMAs

 - "mm/damon: provide pseudo moving sum probe_hits" (SJ Park)

   Integrate DAMON's probe_hits attribute counter into the pseudo moving
   sum infrastructure, enabling real-time, online monitoring without
   waiting for full aggregation intervals

 - "mm: Some cleanups for page allocator APIs" (Brendan Jackman)

   Simplify and refactor the page allocator entry points and flags by
   unifying allocation paths, adding internal alloc_flags arguments, and
   eliminating redundant __ prefixed alloc_pages variants.

 - "Fix incorrect access of hugetlb pte entries" (Dev Jain)

   Enforce the consistent use of huge_ptep_get() instead of ptep_get()
   for HugeTLB entries and fixes an unaligned address issue in arm64's
   huge_ptep_get() implementation

 - "mm/damon: validate all parameters in the core" (SJ Park)

   Consolidate parameter validation into the DAMON core specifically
   within damon_start() and damon_commit_ctx() to centralize error
   checking, eliminate caller-side redundant checks and to improve
   maintenance efficiency

 - "tools/mm/page_owner_sort: fix filtering and cleanup issues" (Yichong
   Chen)

   Rename is_need() to filter_record() for clearer return semantics, fix
   per-record allocation memory leaks and bound output copies in
   search_pattern() to address an existing buffer issue

 - "memcg: bail out reclaim when memcg is dying" (Jiayuan Chen)

   Mitigate a system-wide stall which occurs when a cgroup is removed
   while one of its memory control files is doing synchronous reclaim

 - "mm/memory-failure: add panic option for unrecoverable pages" (Breno
   Leitao)

   Introduce an opt-in vm.panic_on_unrecoverable_memory_failure sysctl
   that immediately panics the kernel on unrecoverable memory errors in
   kernel-owned pages to preserve error context and prevent delayed,
   silent data corruption

 - "mm/damon: refactor damon_{start,stop,commit}() for simple error
   handling" (SJ Park)

   Refactor the DAMON core API functions to guarantee that all contexts
   are fully stopped when damon_start(), damon_stop(), or damon_commit()
   fail, eliminating the need for complex and error-prone caller-side
   cleanup code

 - "Keep tail page private zero at free and folio split" (Zi Yan)

   Add checks to ensure tail_page->private is zero when freeing compound
   or high-order pages and when promoting tail pages during large folio
   splits. By validating these fields at free and split time, it allows
   the removal of redundant private field clearing inside
   prep_compound_tail()

 - "mm: drop redundant lru_add_drain in anon folio reuse paths" (Barry
   Song)

   Eliminate redundant lru_add_drain() calls in
   wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock
   contention and system overhead

   By validating folio refcounts against the LRU cache before draining
   and removing unnecessary drains in the swap path, it achieves up to a
   30.5% reduction in drain calls during heavy swap workloads

 - "mm: clean up folio LRU and swap declarations" (Jianyue Wu)

   Reorganize folio LRU and swap code by relocating page-cluster state
   to mm/swap_state.c, renaming mm/swap.c to mm/folio.c, and moving
   MM-internal reclaim declarations into mm/internal.h.

 - "userfaultfd: working set tracking for VM guest memory" (Kiryl
   Shutsemau)

   Add userfaultfd support for tracking the working set of VM guest
   memory, so a VMM can identify hot pages and reclaim cold ones to
   tiered or remote storage

 - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 2)" (David
   Hildenbrand)

   Remove the remaining pieces of CONFIG_HAVE_BOOTMEM_INFO_NODE,
   performing some smaller cleanups around freeing of reserved vmemmap
   pages on the way.

 - "mm/damon: update probe hits for runtime parameter commits" (SJ Park)

   Ensure that DAMON's probe_hits attribute counter is properly updated
   when monitoring intervals are changed at runtime, matching the
   behavior of nr_accesses. To achieve this, it refactors and renames
   existing helper functions for shared use, applies the updates to
   probe_hits, and handles edge cases in damon_probe_hits_mvsum() to
   maintain measurement accuracy.

 - "KSM: performance optimizations for rmap_walk_ksm" (xu xin)

   Resolve a severe KSM reverse-mapping performance bottleneck where
   thousands of split VMAs sharing a single anon_vma cause extended lock
   contention.

   By adding an interval-filtering check during the rmap walk, it
   reduces worst-case anon_vma lock hold times from over 500ms down to
   under 2ms, preventing application freezes and latency spikes under
   memory pressure.

 - "mm: split a couple of headers from internal.h" (Mike Rapoport)

   Split declarations related to mm_init, memblock, vmalloc and sparse
   into new headers

 - "KSM: use linear_page_index in collect_procs_ksm()" (xu xin)

   Apply the interval tree optimization from rmap_walk_ksm() to
   collect_procs_ksm() to avoid iterating over non-matching VMAs during
   KSM memory error handling.

   It hoists loop-invariant address initialization and restricts the
   anon_vma_interval_tree_foreach walk to a targeted page offset range,
   reducing redundant checks and improving lookup efficiency.

 - "selftests/mm: avoid false failures in hugetlb and KSM tests" (Sayali
   Patil)

   Fix issues in the hugetlb and KSM MM selftest categories that can
   report failures when the prerequisites for the tests are not
   satisfied

 - "mm/damon: introduce data attributes only monitoring" (SJ Park)

   Introduce attribute-weighted region management in DAMON, allowing
   users to prioritize specific data attributes (such as page sizes or
   cgroups) over or instead of access monitoring.

   By assigning weights to attribute probes, DAMON can completely
   disable access tracking and adjust monitoring regions based on
   weighted probe-hit counters to optimize monitoring quality for
   attribute-focused workloads.

 - "mm/hmm: Add mmap lock-drop support for userfaultfd-backed mappings"
   (Stanislav Kinsburskii)

   Extend hmm_range_fault() to support userfaultfd-backed regions by
   allowing the mmap lock to be dropped during fault handling via a new
   hmm_range_fault_locked() helper.

   By accepting a locked pointer and signaling retry status when lock
   release occurs, it enables page fault resolution in userfaultfd
   regions while preserving backward compatibility for existing callers.

 - "mm: make VMA page offset handling more consistent" (Lorenzo Stoakes)

   Clean up and standardize how vma->vm_pgoff is accessed and
   manipulated across file-backed and anonymous mappings in the kernel

   It introduces dedicated helper functions such as vma_start_pgoff(),
   vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while
   renaming rmap interval tree helpers to better reflect their
   functionality.

   These changes establish a cleaner foundation for future work that
   will unify virtual page offset indexing for all anonymous and CoW'd
   folios.

 - "mm: handle device-private PMDs in walk callbacks" (Usama Arif)

   Address kernel panics and state corruption caused by MM walk
   callbacks reaching non-present device-private PMD swap entries
   created during HMM migrations

   It ensures that functions which acquire pmd_trans_huge_lock()
   properly recognize device-private PMDs instead of assuming a present
   THP or a standard migration entry.

 - "mm/rmap: Refactor try_to_unmap_one" (Dev Jain)

   Refactor try_to_unmap_one by modularizing Hugetlb,
   anonymous-lazyfree, and anonymous-swapbacked logic into dedicated
   functions, laying the structural groundwork for batched anonymous
   large folio unmapping.

 - "Docs/ABI/damon: sysfs ABI document fixes and additions" (Song Hu)

   Fix typos and fills in missing entries in the DAMON sysfs ABI
   document

 - "dax/kmem: atomic whole-device hotplug via sysfs" (Gregory Price)

   Introduce an atomic sysfs state attribute and supporting DAX/MM
   infrastructure to prevent userland races when offlining and removing
   entire memory regions

   By adding an unplugged state alongside standard online modes, it
   enables whole-device atomic hotplug control while preserving backward
   compatibility.

 - "mm: convert more vm_flags_t users to vma_flags_t" (Lorenzo Stoakes)

   Continue transitioning the kernel from the deprecated vm_flags_t type
   to vma_flags_t across core memory management infrastructure.

   It replaces legacy type usage in core functions such as do_mmap(),
   unmapped area allocation, mm->def_vma_flags, and VMA operations like
   mlock, mprotect, and mremap.

 - "Two small patches to clean up mm/mm_slot.h" (xu xin)

   Refactor mm_slot.h by introducing mm_slot_remove() to unify duplicate
   slot deletion sequences in khugepaged and KSM. It also adds code
   documentation explaining why mm_slot_lookup and mm_slot_insert must
   remain as preprocessor macros rather than static inline functions.

 - "mm/damon/core: hide core-private struct fields" (SJ Park)

   Clean up DAMON core structures by consistently marking internal-only
   fields with private: comment tags to prevent improper direct access
   from outer layers.

   It enforces encapsulation across core structures including
   damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to
   interact through approved access APIs instead of exposing raw struct
   members.

 - "mm/damon: unurgent fixes for infinite loop, NULL de-ref and races"
   (SJ Park)

   Address potential infinite loops, NULL dereferences, and race
   conditions identified in DAMON

   It fixes an infinite loop triggered by extreme user configurations, a
   NULL pointer dereference within unit tests and minor monitoring
   accuracy degradation caused by subtle runtime races.

 - "mm/page_alloc: fixes for free_pages_nolock() on RT/UP" (Brendan
   Jackman)

   Fix an NMI safety flaw in __free_frozen_pages() where freeing pages
   on non-SMP or PREEMPT_RT kernels can bypass can_spin_trylock() checks
   via non-PCP or isolated migration paths.

   It also resolves potential kernel crashes and privilege escalation
   risks triggered when BPF tracing runs in NMI context alongside memory
   hotplug or large allocation frees.

 - "mm/page_alloc: couple of followups for recent cleanups" (Brendan
   Jackman)

   Clean up and update page allocator nomenclature, documentation, and
   debug assertions.

   It aligns internal FPI_ flags with the public "nolock" naming
   convention, removes outdated internal implementation details from
   high-level page allocator comments, and eliminates obsolete
   VM_BUG_ON() assertions in allocation paths.

 - "mm/mseal: further cleanups" (Lorenzo Stoakes)

   Refactor and simplify the mseal implementation by clarifying API
   boundaries and removing unnecessary code complexity.

   It replaces generic do_mseal() usage outside the syscall with a
   dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO,
   eliminates mm_struct parameters to enforce that sealing applies only
   to current->mm, and streamlines overall logic and comments with no
   functional changes intended.

 - "mm/vmscan: fix swappiness=max and clean up per-node proactive
   reclaim" (Ridong Chen)

   Resolve reclaim behavior bugs and clean up function parameters across
   memory reclaim paths

   It fixes swappiness=max in both standard reclaim and MGLRU so
   unswappable anonymous memory no longer falls back to evicting page
   cache, ensures reclaim_store() returns accurate error codes instead
   of collapsing all failures into -EAGAIN, and removes the obsolete
   gfp_mask parameter from __node_reclaim().

 - "mm: mincore: misc cleanups" (Kefeng Wang)

   Clean up and simplifies the mincore code. Most importantly, it
   removes the historical special behavior that always reports VM_PFNMAP
   pages as non-resident.

 - "mm/huge_memory: drop dead split helper variants" (Kiryl Shutsemau)

   Two trivial cleanups in the folio split API

 - "mm/damon: fix uninitialized DAMOS field and kunit exec expectation
   bugs" (SJ Park)

   Resolve minor operational and testing bugs in DAMON identified by
   Sashiko. It initializes the damos->last_applied field to prevent
   occasional efficiency degradation and fixes invalid memory accesses
   in DAMON KUnit tests during test failure handling.

 - "cleanup for stable_page_flags()" (Jinjiang Tu)

   Clean up and refactor stable_page_flags() used by /proc/kpageflags
   without altering functionality.

   It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag
   bits, converts folio-specific flag checks to standard folio_test_*()
   helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling.

 - "Batch unmap of uffd-wp file folios" (Dev Jain)

   Extend batched folio unmapping support to file folios within
   userfaultfd write-protect (uffd-wp) VMAs by adding batching
   capabilities to pte_install_uffd_wp_if_needed().

   This removes special-case restrictions on uffd-wp VMAs in
   try_to_unmap_one(), significantly simplifying the function's control
   flow and complexity.

 - "mm/early_ioremap: clarify and clean up early_ioremap_reset()"
   (Sang-Heon Jeon)

   Clarify and clean up the architecture-specific usage of
   __late_set_fixmap() and __late_clear_fixmap() after
   early_ioremap_reset()

   It adds explicit documentation regarding when early_ioremap_reset()
   must be called and removes redundant macro definitions and reset
   calls in the RISC-V and ARM64 architectures.

 - "mm: fix reclaim storms in defrag_mode" (Johannes Weiner)

   Address severe performance regressions, swap storms, and spurious
   OOMs caused by vm.defrag_mode=1 under high memory pressure in Meta
   production

   It updates the page allocator slowpath so non-movable allocation
   requests actively trigger direct reclaim and direct compaction at
   pageblock_order scale, allowing them to claim whole pageblocks rather
   than spinning unproductively.

 - "zram: lockmap tweaks" (Sebastian Siewior)

   Optimize and fix lockdep tracking for zram devices by consolidating
   per-entry lockmaps and isolate lock classes across multiple instances

   This reduces memory overhead by replacing per-entry lockdep_map
   instances with a single map per struct zram, and assigns a dynamic
   lock_class_key to each instance to prevent false deadlock reports
   when different zram devices are backed by distinct filesystems.

* tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (501 commits)
  selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check
  selftests/mm: unpoison pages in memory-failure teardown
  mm/shmem: downgrade final i_blocks check in shmem_evict_inode() to pr_warn()
  mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro
  mm/zsmalloc: fix release order of locks in zs_page_migrate()
  Documentation: zram: remove sections numbering
  ksm: stop iterating VMAs when ksm_test_exit returns true
  mm: fold userfaultfd_rwp() to false without CONFIG_ARCH_HAS_PTE_PROTNONE
  mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch()
  zram: use a custom key for each zram object
  zram: move lockmap to be per-zram instead per table
  selftests/mm: fix gup_longterm EINVAL error message
  mm: page_alloc: fix non-movable reclaim storm in defrag_mode
  mm: page_alloc: move capture_control to the page allocator
  mm: compaction: support non-movable compaction for pageblock requests
  mm: page_alloc: __GFP_FS lockdep annotation for direct compaction
  hugetlb: evaluate subpool free state while locked
  mm/damon: remove trailing semicolons after function definitions
  mm/damon/ops-common: prevent migration fallback to non-target nodes
  mm/damon: update outdated comment about DAMOS filter handling
  ...
2026-08-20 18:17:08 -07:00
Linus Torvalds
caf325ab81 LoongArch changes for v7.3
1, Add DIRECT_MAP_PHYSMEM_END definition;
 2, Expand module virtual address space to 2GB;
 3, Use current_stack_pointer in current_pt_regs();
 4, BPF JIT enhancements such as kptr_xchg and timed may_goto;
 5, Some bug fixes and other small changes.
 -----BEGIN PGP SIGNATURE-----
 
 iQJKBAABCAA0FiEEzOlt8mkP+tbeiYy5AoYrw/LiJnoFAmqDGUUWHGNoZW5odWFj
 YWlAa2VybmVsLm9yZwAKCRAChivD8uImeiE5D/0XYl8xAsOegm2dNuM+kKfqXAV4
 FcbaoB7GuYHWG7lFkVTITwBe8A30BInADrwZQPxv7wb7aTQusTwNjAfq1pX1MOxG
 ET1Fady7dEokCB9VAS/FP24lbF5nDYLVs0kEcx+xvAwQpW750Rk+aWcyCZeX5xgV
 3KrlnYVXDvDYY6HDeuL9pXkKhyRe4uqnPLh1loOhK0HC/NhLCu+tfyLH3pQl/ZCf
 QuNnw93fSTJPvZD2HcTb81tG4ohdj5GXM9SuckfIvNiZoRtc5pMnVE6we1N5yQKY
 E4EwB9fqQ74piMbM2RjLPi5bjgzzdJSGamdEZ4QUau4HjFXZsDiNEfWRmN2Z3qQo
 +zsLzZq43yHsCUsaobWmtmo0Q6YF4pjtyff904YYrPIKH+96dyGsvjbA+n46H7pL
 Eg+HNdOH0t6dU706y0zbR0t1Za4PiM9dZtV3BZT3B8MLMEy7dsVYoBUt+7Kc+eYB
 lq5SlWaFYyOSnC1WL8/uzzrH6adF/62DruHy1ovlWOE6bhPc+uQucXHOyNxyf86h
 xIlOB0hRCO18sYql6WuxpQO9bKP0LCQv5JoeCqjXsKTQgiG3kFAx9bpRmTHt4CqH
 3LWiBRRVzLvScZ0qqerGXXylXXkdN3uagtpSXM+f/bXbWje3cROSyWK4rktwLsPN
 ugAIATgZ8+/B45X56w==
 =h0m2
 -----END PGP SIGNATURE-----

Merge tag 'loongarch-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch updates from Huacai Chen:

 - Add DIRECT_MAP_PHYSMEM_END definition

 - Expand module virtual address space to 2GB

 - Use current_stack_pointer in current_pt_regs()

 - BPF JIT enhancements such as kptr_xchg and timed may_goto

 - Some bug fixes and other small changes

* tag 'loongarch-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  selftests/bpf: Enable kptr_xchg_inline test on LoongArch
  LoongArch: BPF: Add arch_bpf_stack_walk() implementation
  LoongArch: BPF: Add timed may_goto implementation
  LoongArch: BPF: Resolve per-CPU addrs for internal-only MOV
  LoongArch: BPF: Advertise JIT support for kptr xchg inline
  LoongArch: BPF: Align value-returning atomics with LKMM
  LoongArch: BPF: Split unconditional branch JA paths statically
  LoongArch: BPF: Remove dead move_imm() call in BPF_NEG path
  LoongArch: BPF: Remove redundant zext jumping in move_imm()
  LoongArch: BPF: Implement branchless conditional move for TCC
  LoongArch: BPF: Refactor jump offset calculation in tail call
  LoongArch: BPF: Move arena register slot below TCC context
  LoongArch: BPF: Optimize redundant TCC loads in epilogue
  LoongArch: Use current_stack_pointer in current_pt_regs()
  LoongArch: Use generic cmp_int() instead of custom cmp_3way()
  LoongArch: Expand module virtual address space to 2GB
  LoongArch: Add DIRECT_MAP_PHYSMEM_END definition
  LoongArch: Fix acpi_package_ids[] array overflow
2026-08-20 14:46:50 -07:00
Linus Torvalds
9328b3b03b \n
-----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEq1nRK9aeMoq1VSgcnJ2qBz9kQNkFAmqFw00ACgkQnJ2qBz9k
 QNlJlgf/SylCykcdsaqBVJd9hTrg0L6AdMKyc/PpdvyjK7qWOrXLzQFV9p7BHrER
 pGixy+k/5QTlWRAQ7X7okHI9uo6cMzxP/OeLqiXszBPlinRxsELb1GH89+5jOrQh
 oAcDci0LxX9dyBXcnl+MFgS6FPURQRnGqCeyMc+EnqHF8LYTjy05jWw/sn8Ok6WF
 vTBV1gl1YLN6bA+cRDVH3BBWf9irzDvnbBTUo6CRF0H5wPxiuy/ddgaYxgd8GDD/
 jKsZ/hmL90695CGmvoGC3WtMpAUJm/rLX6aqoYltwQYbKhVJpfAh58IhJGpgsRG4
 l4kVxtZvjvP5jMskXm5SbCMAzB8Fzg==
 =vznt
 -----END PGP SIGNATURE-----

Merge tag 'fs_for_v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull ext2, udf, isofs, and quota updates from Jan Kara:

 - Remove deprecated quota code printing warnings about exceeded quota
   directly to console

 - Various udf & isofs hardening for handling of corrupted filesystems

 - Fix a possible data loss in udf when converting files from inline to
   out-of-line format

 - Simplify EIO error handling in ext2 xattr code

* tag 'fs_for_v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Fix data loss when converting inline inodes to out of line
  udf: Move udf_map_block() up
  ext2: Simplify error handling of IO error when adding xattr
  isofs: Drop support of directory entries straddling blocks
  isofs: validate directory records consistently
  quota: remove CONFIG_PRINT_QUOTA_WARNING code
  udf: Fix i_lenExtents truncation on 32-bit kernels
  isofs: release zisofs block pointer buffer head
  udf: Fix bh leak for unallocated space entries
  udf: bound lengthAllocDescs from unallocated space entry
  UDF symlink pathComponent header OOB read
  isofs: fix out-of-bounds page array access on empty zisofs block
  udf: reject VAT indexes equal to the entry count
  udf: Mark LVID buffer as uptodate before marking it dirty
  udf: avoid recursive s_alloc_mutex deadlock when freeing AED blocks
  udf: validate extent partition references in udf_current_aext()
2026-08-20 12:52:35 -07:00
Linus Torvalds
104a813376 VDSO updates:
- Consolidate the VDSO datastore further and provide support for
    mlock_all() and prefaulting.
 
  - Provide 32-bit legacy time related functionality only if
    CONFIG_COMPAT_32BIT_TIME is enabled. The config switch exists, but
    architecture code still exposes the legacy functionality even disabled.
 
    Clean this up by adding the missing guards and validating at build time
    that the VDSO is legacy free if disabled.
 
  - Consolidate the VDSO related config options in core and drivers, which
    removes some non-sensical dependencies and quite an amount of #ifdeffery.
 
  - Clean up the PAGE_SIZE definition maze
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCgAuFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmqCxfkQHHRnbHhAa2Vy
 bmVsLm9yZwAKCRCmGPVMDXSYoSQkEADEOmcrm3vwMbaElrAfQRp4MOQMnDpKPCDa
 0EwdkXKJyqfOGx1PNKbcWZe10qShpXqyz+q3MUbHiOVh7KxkaGj0GOA/+xD+Tgs5
 RAFXCq+CY4Ccjix7vlyOBLvGgomuznAtRDCFprVq5OTXyQfVvS++5SHzaU/0xXiY
 ZZEInrFP61BEJ8LJycpoN5431EBcUX7XpSkr9eHtuSOslOBzbTEtBbDp0AjDGse0
 5qM/oZDufZDQQr31kVQiL0dN9bBWwdGNtBwZBjsf6KioY9M00LO0E9twSCSrI39F
 kgD2N97RDjTewu/zEe0fvCDVypqel2mBvjfiYU4c8g6pprdJ4Hq1qMcDAtMBUDBZ
 9jR8B09eYZwHLdbM5PFjiMf9d6p25P7X+twFI9Hylcm1YZtM4OTnamDhQOQDp1Fd
 QdrFevXg1zvYVi1rrDYarcPfg/tGsetOTujMQ1m50/AJZOoEdcX9jZR/wfdW8ti6
 X9TIn3SDzhauXkmeR86tHxtOmHDirVfBWCCCEyVT2YzGIIje25cf266fCPdcGRYl
 kzhtycg8LqpTRMWjhlaf56NtD9qQlbvDY8L23tQLJUYhDp8xOxqyuRPRdpJVM0b3
 4vp/Z8Sgz8tpEHO2ARsXfuu2CzilTBH0B2KL3f+a8CwpzIEadjIfc+6EEYqwgOAn
 +/RhckFp/A==
 =jHl1
 -----END PGP SIGNATURE-----

Merge tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull VDSO updates from Thomas Gleixner:

 - Consolidate the VDSO datastore further and provide support for
   mlock_all() and prefaulting.

 - Provide 32-bit legacy time related functionality only if
   CONFIG_COMPAT_32BIT_TIME is enabled. The config switch exists,
   but architecture code still exposes the legacy functionality even
   disabled.

   Clean this up by adding the missing guards and validating at build
   time that the VDSO is legacy free if disabled.

 - Consolidate the VDSO related config options in core and drivers,
   which removes some non-sensical dependencies and quite an amount of
   #ifdeffery.

 - Clean up the PAGE_SIZE definition maze

* tag 'timers-vdso-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  random: vDSO: Drop custom PAGE_SIZE definitions
  LoongArch: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/timer-riscv: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/arm_arch_timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  clocksource/drivers/mips-gic-timer: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  MIPS: csrc-r4k: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
  vDSO: Make clockmode constants available without CONFIG_GENERIC_GETTIMEOFDAY
  kbuild: Support generated asm-headers in subdirectories
  vdso: Rename HAVE_GENERIC_VDSO to VDSO_DATASTORE
  vdso: Drop HAVE_GENERIC_VDSO from architecture kconfig files
  vdso: Automatically select HAVE_GENERIC_VDSO if necessary
  MIPS: vdso: Stop using CONFIG_HAVE_GENERIC_VDSO
  vdso: Remove the dependency on HAVE_GENERIC_VDSO from ARCH_HAS_VDSO_ARCH_DATA
  futex: Remove dependency on HAVE_GENERIC_VDSO from FUTEX_ROBUST_UNLOCK
  vdso/gettimeofday: Verify COMPAT_32BIT_TIME interactions
  sparc: vdso: Respect COMPAT_32BIT_TIME
  MIPS: VDSO: Respect COMPAT_32BIT_TIME
  powerpc/vdso: Respect COMPAT_32BIT_TIME
  ARM: VDSO: Respect COMPAT_32BIT_TIME
  arm64: vdso32: Respect COMPAT_32BIT_TIME
  ...
2026-08-18 16:56:25 -07:00
Linus Torvalds
3424d8c18a Generic entry code updates:
- Make syscall user dispatching configurable
 
     Not all architectures can makes use of syscall user dispatching. Allow
     them to disable the feature completely.
 
   - Consolidate stack randomization for the generic entry code and the
     architectures using it.
 
     Stack randomization on syscall entry was sprinkled throughout the
     architecture specific low level entry code and in some cases at the
     wrong points, e.g. before establishing state, which violates the
     non-instrumentable constraints of that code.
 
     Clean this up by integrating stack randomization into the generic entry
     code helpers so that it is invoked at the earliest possible point right
     after establishing state and converting all generic entry code using
     architecture over.
 
   - Clean up the syscall number handling in the generic entry code. It
     works correctly for architectures which have a separate return value
     storage in pt_regs, but fails to distinguish the case where user space
     handed in -1 as syscall number from the case where the entry code
     rejects it by returning -1 to the callers. Aside of that the return
     value functionality of those interfaces is not really intuitive.
 
     Fix this by separating the decision to reject a syscall (user dispatch,
     ptrace, seccomp ...) from the potential modification of the syscall
     number through these mechanisms.
 
     This solves most of the problems for architectures which do not have a
     separate return value storage in pt_regs except for the case where a
     tracepoint has a BPF script or a probe attached which overwrite both
     the syscall number and the return value. But that's a problem which
     cannot be solved in the generic code, that only can be addressed by
     separating the storage model in the affected architectures.
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCgAuFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmqCs10QHHRnbHhAa2Vy
 bmVsLm9yZwAKCRCmGPVMDXSYoaf6D/0ZBG1Yb0/C/6lrI185qPu38aGOROuAcxP+
 RV1O1x6C83w2hCLBH8LeswY2x4/iGbdftne/hfmvu8eNCE5MzBfYvXhLL4If75Tc
 IJ6C8uummnDmrT1TFuWHryTAfjyF28gt0+GGq0Zy5Hyz9b4CTJqOMx5u6KV4cZuJ
 odoNQpE/GlWo40wCSTYP/Tt5xONrogk2pMQtFyV8JEoaXkdYSj/V815yojEmofYU
 fmgPPO5/vOnZzE4b29gZyndXnU1Boah7r1l5fg7c9za376yCEEzh/ApPhovHyY0A
 t8zjnrtooZ27IUKbcsyycrAM14asfcmViDNDgaCj8ttBioQaCnxO1BpKWjVxEZhE
 AbM6q3Q66ER4Df6GNhZjPqT5Lr7E7+vLLarhXLWztsGQklIx4AFbrsa73hA20UC9
 1PSeMd45JSxH3yA8vMauXAGHFK1tD1V8Lgofu69+2Z3jtKB+aU0fqWeL1jesSEM0
 oCGhUb3hIC1pz3KVA0MGmNTm0yyQJYTGZL7wADYNV5NbxJVqXgo37qa/0n94Gf/4
 TG3OwY4Sb/H/sve7v/eY4IvxVh+xs3dLZP8ZoqMlPCp9JIxc6iNoe6VHqPI7PFnM
 fXwDtsy+bRF/SKnB/32qxnR7UJqmdNH3XIjd+lXWliKt6UYoC79/MEKN5DmJcO9P
 CykZUWa72A==
 =XUd9
 -----END PGP SIGNATURE-----

Merge tag 'core-entry-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull generic entry code updates from Thomas Gleixner:

 - Make syscall user dispatching configurable

   Not all architectures can makes use of syscall user dispatching.
   Allow them to disable the feature completely.

 - Consolidate stack randomization for the generic entry code and the
   architectures using it.

   Stack randomization on syscall entry was sprinkled throughout the
   architecture specific low level entry code and in some cases at the
   wrong points, e.g. before establishing state, which violates the
   non-instrumentable constraints of that code.

   Clean this up by integrating stack randomization into the generic
   entry code helpers so that it is invoked at the earliest possible
   point right after establishing state and converting all generic entry
   code using architecture over.

 - Clean up the syscall number handling in the generic entry code. It
   works correctly for architectures which have a separate return value
   storage in pt_regs, but fails to distinguish the case where user
   space handed in -1 as syscall number from the case where the entry
   code rejects it by returning -1 to the callers. Aside of that the
   return value functionality of those interfaces is not really
   intuitive.

   Fix this by separating the decision to reject a syscall (user
   dispatch, ptrace, seccomp ...) from the potential modification of the
   syscall number through these mechanisms.

   This solves most of the problems for architectures which do not have
   a separate return value storage in pt_regs except for the case where
   a tracepoint has a BPF script or a probe attached which overwrite
   both the syscall number and the return value. But that's a problem
   which cannot be solved in the generic code, that only can be
   addressed by separating the storage model in the affected
   architectures.

* tag 'core-entry-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  entry, treewide: Make syscall_enter_from_user_mode[_work]() indicate syscall execution
  entry: Make return type of syscall_trace_enter() bool
  entry: Rework trace_syscall_enter()
  entry: Rework syscall_audit_enter()
  syscall_user_dispatch: Introduce ARCH_SUPPORTS_SYSCALL_USER_DISPATCH
  entry: Fix seccomp bypass after ptrace with TSYNC
  x86/entry: Simplify the syscall number logic
  x86/entry: Get rid of the sys_ni_syscall() indirection
  x86/entry: Make syscall functions static
  ptrace, treewide: Rename ptrace_report_syscall_entry() to ptrace_report_syscall_permit_entry()
  seccomp, treewide: Rename and convert __secure_computing() to return boolean
  entry: Use syscall number instead of rereading it
  entry: Remove syscall_enter_from_user_mode()
  x86/syscall: Use [syscall_]enter_from_user_mode_randomize_stack()
  s390/syscall: Use enter_from_user_mode_randomize_stack()
  riscv/syscall: Use syscall_enter_from_user_mode_randomize_stack()
  powerpc/syscall: Use syscall_enter_from_user_mode_randomize_stack()
  loongarch/syscall: Use syscall_enter_from_user_mode_randomize_stack()
  entry: Provide [syscall_]enter_from_user_mode_randomize_stack()
  randomize_kstack: Provide add_random_kstack_offset_irqsoff()
  ...
2026-08-18 15:00:56 -07:00
Linus Torvalds
ba24659b1d kexec: updates for v7.3-rc1
* Deduplicate crash memory allocation and the exclusion of reserved crash
   kernel regions from architecture specific code into a generic
   crash_prepare_headers() and enable crashkernel CMA reservation on arm64 and
   riscv reservation on arm64 and riscv.
 * Skip purgatory checksum verification when the kexec segments cannot be
   corrupted by DMA, which saves about 250ms on kexec.
 * Replace __ASSEMBLY__ with the compiler provided __ASSEMBLER__ in
   include/linux/kexec.h.
 * Fix a keyring refcount imbalance in the kdump kernel's dm-crypt key restore
   path, which over-dropped the user keyring reference when more than one key
   was restored.
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEEeOVYVaWZL5900a/pOQOGJssO/ZEFAmp9ouoACgkQOQOGJssO
 /ZEH/Af/b1qmnw8uUe2wzd1zcAEEsk6YwF8lmS5o4k7skiVKlHWQuDzPrwrxFTvg
 d6obJrLllMN2ULyLQ8ghMKbsdo8RCGBIpXF+bPEXmIF8bA/PhtDaxvi3scsxvie6
 zU3geZbExlzg0Ik525I0DyPoEZc2JAg5ietp8bF6ZN5HNkDtBoNvi2ROc4mR9kzO
 agrczVnIEuIE3Tk+IfD6081iS3Wz/PjRC+yPBU1yYFobA6/bL7kFma7kED8PnxvI
 2+oENcd1FtC/WBlmluZE0BC4SjNcsT1geyzAFlGlRvNzbHdtj13j6mTBSsbRpJMW
 WdewVpIpFGUqRbUIIdvOISLOcf62lg==
 =PjFs
 -----END PGP SIGNATURE-----

Merge tag 'kexec-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux

Pull kexec updates from Mike Rapoport:

 - Deduplicate crash memory allocation and the exclusion of reserved
   crash kernel regions from architecture specific code into a generic
   crash_prepare_headers() and enable crashkernel CMA reservation on
   arm64 and riscv reservation on arm64 and riscv.

 - Skip purgatory checksum verification when the kexec segments cannot
   be corrupted by DMA, which saves about 250ms on kexec.

 - Replace __ASSEMBLY__ with the compiler provided __ASSEMBLER__ in
   include/linux/kexec.h.

 - Fix a keyring refcount imbalance in the kdump kernel's dm-crypt key
   restore path, which over-dropped the user keyring reference when
   more than one key was restored.

* tag 'kexec-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux:
  crash_dump: release keyring reference at the correct time
  kexec: Replace __ASSEMBLY__ with __ASSEMBLER__ in header file
  kexec_file: skip checksum verification when safe
  riscv: kexec_file: Add support for crashkernel CMA reservation
  arm64: kexec_file: Add support for crashkernel CMA reservation
  powerpc/kexec_file: Use crash_exclude_core_ranges() helper
  LoongArch: kexec_file: Use crash_prepare_headers() helper to simplify code
  riscv: kexec_file: Use crash_prepare_headers() helper to simplify code
  x86/crash: Use crash_prepare_headers() helper to simplify code
  arm64: kexec_file: Use crash_prepare_headers() helper to simplify code
  crash: Add crash_prepare_headers() to exclude crash kernel memory
  powerpc/crash: sort crash memory ranges before preparing elfcorehdr
  riscv: kexec_file: Fix crashk_low_res not exclude bug
2026-08-18 10:28:28 -07:00
Linus Torvalds
38fda1d9d2 memblock: updates for 7.3-rc1
Non-urgent fixes:
 
 * Fix calculation of node_spanned_pages when running with kernelcore=mirror
 * Properly handle failure to allocate per_cpu_nodestats in
   free_area_init_core_hotplug()
 * Fix deferred initialization of the memory map for configurations where
   node's RAM end is not aligned on PAGES_PER_SECTION
 
 Cleanups:
 
 * Remove redundant pageblock_align() call in free_unused_memmap()
 * Remove unnecessary invalid range checks in users of memblock iterators.
   Some users of for_each_mem_range() and for_each_mem_pfn_range() verify
   that start < end for each range. This is redundant because memblock
   iterators guarantee to never return an invalid range
 * Stop overlapping zones with kernelcore=mirror and align behaviour of
   kernelcore=mirror with other variants of kernelcore=/movablecore=
 * Remove redundant updates of numa_nodes_parsed mask in the callers of
   numa_add_memblk(), the latter always updates the mask anyway
 * Remove unnecessary initialization of pgdat->per_cpu_nodestats to NULL,
   the variable is reset to the actual value a few lines below
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEEeOVYVaWZL5900a/pOQOGJssO/ZEFAmp9lIIACgkQOQOGJssO
 /ZEgNggAgzHeTtb+CK6s4mXlkIaoau/7I/nxmvl9/EwH4uNZrRSn7lKOp7FkTYk0
 IvtrMj8XspA8vDMzkxAutVfgGFo7zItzpkIF8Y8r6vbP+fhZhieZ6NnxeyjEfYJJ
 /r800vL+Q8ru0WUv5qsiBwlRC3RNoVQvO2zLsoBUbBqNluv9L+eDrs7pgcVbrkhy
 r3rDHjnj2v9mqPZl+CTGifCWq0y40bhcw0dbRpn7165c2qwEMSwlan5ERuaZmja1
 NJrWNiqYxD7mQ3DyDIc4C9jvZaHLkVkaAE6uRrTXb1rJFmyh/ghQ4YdTZ9GTcEVP
 6AQk/eX3V3k5QUVngJBFqUq/kD2eIQ==
 =vCS2
 -----END PGP SIGNATURE-----

Merge tag 'memblock-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock

Pull memblock updates from Mike Rapoport:
 "Non-urgent fixes:

   - Fix calculation of node_spanned_pages when running
     with 'kernelcore=mirror'

   - Properly handle failure to allocate per_cpu_nodestats
     in free_area_init_core_hotplug()

   - Fix deferred initialization of the memory map for
     configurations where node's RAM end is not aligned
     on PAGES_PER_SECTION

  Cleanups:

   - Remove redundant pageblock_align() call in free_unused_memmap()

   - Remove unnecessary invalid range checks in users of memblock
     iterators. Some users of for_each_mem_range() and
     for_each_mem_pfn_range() verify that start < end for each range.

     This is redundant because memblock iterators guarantee to never
     return an invalid range

   - Stop overlapping zones with 'kernelcore=mirror' and align behaviour
     of 'kernelcore=mirror' with other variants of kernelcore and
     movablecore

   - Remove redundant updates of numa_nodes_parsed mask in the callers
     of numa_add_memblk(), the latter always updates the mask anyway

   - Remove unnecessary initialization of pgdat->per_cpu_nodestats to
     NULL, the variable is reset to the actual value a few lines below"

* tag 'memblock-v7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock: (25 commits)
  mm/mm_init: deferred_grow_zone(): fix out-of-range first_deferred_pfn
  mm/mm_init: remove unnecessary initialization of pgdat->per_cpu_nodestats
  mm/mm_init: remove redundant memset in free_area_init()
  mm: numa_memblks: use numa_add_reserved_memblk() in numa_cleanup_meminfo()
  arch_numa: remove redundant node_possible_map assignment
  mm: numa_memblks: remove redundant numa_nodemask_from_meminfo()
  LoongArch: remove redundant numa_nodes_parsed node_set()
  arch_numa: remove redundant numa_nodes_parsed node_set()
  x86/numa: remove redundant numa_nodes_parsed node_set()
  of/numa: remove redundant numa_nodes_parsed node_set()
  ACPI: NUMA: remove redundant numa_nodes_parsed node_set()
  mm: numa_memblks: set numa_nodes_parsed in numa_add_memblk()
  mm/mm_init: handle alloc_percpu failure in free_area_init_core_hotplug
  mm/mm_init: drop overlap_memmap_init()
  mm/mm_init: don't overlap NORMAL and MOVABLE zones with kernelcore=mirror
  mm/hugetlb: remove unnecessary empty range check in hugetlb_bootmem_set_nodes()
  mm: remove unnecessary empty range check in early_calculate_totalpages()
  powerpc64/kasan: Remove unreachable invalid range check in kasan_init_phys_region()
  ARM: remove unreachable invalid range check in kasan_init()
  riscv: remove unreachable invalid range check in kasan_init()
  ...
2026-08-18 10:03:54 -07:00
Linus Torvalds
1d7443e4dc fscrypt updates for 7.3
The main change this cycle is a significant simplification that's been
 overdue for a while now: standardizing on a single file contents
 encryption implementation in ext4 and f2fs, instead of having two.
 
 Specifically, the original filesystem-layer file contents encryption
 implementation is removed, and the blk-crypto implementation is now
 used unconditionally. blk-crypto delegates either to inline crypto
 hardware or to the CPU via blk-crypto-fallback. The latter is
 functionally equivalent to the original filesystem-layer code.
 
 The blk-crypto implementation already existed, but previously it was
 used only when the filesystem was mounted with "-o inlinecrypt". Now,
 "-o inlinecrypt" just selects whether inline crypto hardware is used.
 
 To allow maintaining that user control over hardware use, the
 blk-crypto API is extended with a new flag BLK_CRYPTO_CFG_ALLOW_HW.
 
 Overall, this removes quite a bit of redundant code from ext4, f2fs,
 and fs/crypto/. It should make things easier for ongoing filesystem
 efforts such as iomap support, large folios, and btrfs encryption.
 (btrfs had already been planning to use blk-crypto exclusively.)
 
 There are two small behavior changes of note:
 
 - Direct I/O now works on encrypted files even without
   "-o inlinecrypt", rather than falling back to buffered I/O. This is
   effectively a bugfix, though I'll continue to keep an eye out for
   any user that may have been depending on the buffered I/O fallback.
 
 - IV_INO_LBLK_32 policies are no longer supported in certain cases
   that didn't make sense and have no known uses.
 
 This has been in linux-next since July 22 with no reported issues.
 All encryption xfstests pass on ext4 and f2fs. As usual I've also been
 using it on a system with an fscrypt-encrypted home directory. Of
 course, the blk-crypto code paths also aren't new and were already
 being used on many systems via the inlinecrypt mount option.
 
 In addition to the main change described above, there are a few other
 cleanups such as using lock guards for mutexes, improving
 documentation, and removing a workaround for outdated gcc versions.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQSacvsUNc7UX4ntmEPzXCl4vpKOKwUCaoDumhQcZWJpZ2dlcnNA
 a2VybmVsLm9yZwAKCRDzXCl4vpKOKwk1AP9gAHdxAK2tr+Wpklkos/qTMR3a7h2I
 xLmgwhLHmHoHTgD/cD+0eMoK4RIVVGS/73Bf7oF2qY5jOyfi1aGh4ERQ0AA=
 =0+o6
 -----END PGP SIGNATURE-----

Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux

Pull fscrypt updates from Eric Biggers:
 "The main change this cycle is a significant simplification that's been
  overdue for a while now: standardizing on a single file contents
  encryption implementation in ext4 and f2fs, instead of having two.

  Specifically, the original filesystem-layer file contents encryption
  implementation is removed, and the blk-crypto implementation is now
  used unconditionally. blk-crypto delegates either to inline crypto
  hardware or to the CPU via blk-crypto-fallback. The latter is
  functionally equivalent to the original filesystem-layer code.

  The blk-crypto implementation already existed, but previously it was
  used only when the filesystem was mounted with "-o inlinecrypt". Now,
  "-o inlinecrypt" just selects whether inline crypto hardware is used.

  To allow maintaining that user control over hardware use, the
  blk-crypto API is extended with a new flag BLK_CRYPTO_CFG_ALLOW_HW.

  Overall, this removes quite a bit of redundant code from ext4, f2fs,
  and fs/crypto/. It should make things easier for ongoing filesystem
  efforts such as iomap support, large folios, and btrfs encryption
  (btrfs had already been planning to use blk-crypto exclusively.)

  There are two small behavior changes of note:

   - Direct I/O now works on encrypted files even without "-o inlinecrypt",
     rather than falling back to buffered I/O. This is effectively a
     bugfix, though I'll continue to keep an eye out for any user that
     may have been depending on the buffered I/O fallback.

   - IV_INO_LBLK_32 policies are no longer supported in certain cases
     that didn't make sense and have no known uses.

  This has been in linux-next since July 22 with no reported issues. All
  encryption xfstests pass on ext4 and f2fs. As usual I've also been
  using it on a system with an fscrypt-encrypted home directory. Of
  course, the blk-crypto code paths also aren't new and were already
  being used on many systems via the inlinecrypt mount option.

  In addition to the main change described above, there are a few other
  cleanups such as using lock guards for mutexes, improving
  documentation, and removing a workaround for outdated gcc versions"

* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux: (29 commits)
  blk-crypto: Update docs for blk-crypto-fallback motivation
  blk-crypto: Remove unused function blk_crypto_config_supported()
  fscrypt: Update docs for data path
  fscrypt: Remove unused function fscrypt_finalize_bounce_page()
  f2fs: Update outdated comment in f2fs_write_begin()
  fs: Update outdated comment for SB_INLINECRYPT
  fscrypt: Update encryption policy version docs
  fscrypt: Replace some variable-size memsets with fixed-size
  fscrypt: Add safety checks to non-block-based en/decryption
  fscrypt: Merge bio.c and inline_crypt.c into block.c
  fscrypt: Remove unused functions and workqueue
  fscrypt: Remove fs-layer zeroout code
  fscrypt: Remove fscrypt_dio_supported()
  fscrypt: Replace calls to fscrypt_inode_uses_inline_crypto()
  fs/buffer: Remove fs-layer decryption code
  f2fs: Remove fs-layer file contents en/decryption code
  ext4: Further de-generalize the bio postprocessing code
  ext4: Make ext4_bio_write_folio() return void
  ext4: Remove fs-layer file contents en/decryption code
  Documentation: fscrypt: Update docs for inlinecrypt
  ...
2026-08-17 19:04:16 -07:00
George Guo
e7103e5e3b LoongArch: BPF: Add arch_bpf_stack_walk() implementation
Implement arch_bpf_stack_walk() on top of the ORC unwinder within
the LoongArch BPF JIT backend to provide generic BPF stack walking
capabilities.

This function is required by advanced BPF features, including timed
may_goto timeout tracing and BPF exceptions. It will be invoked in
the BPF core subsystem unwinding paths: bpf_prog_find_from_stack(),
bpf_stream_stage_dump_stack(), and bpf_throw().

Co-developed-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: George Guo <guodongtai@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:40 +08:00
George Guo
3fbf3534c2 LoongArch: BPF: Add timed may_goto implementation
Implement arch_bpf_timed_may_goto() support and advertise it through
bpf_jit_supports_timed_may_goto() so the verifier lowers may_goto into
the timed variant: instead of a fixed iteration counter, the loop is
bounded by a wall-clock timeout maintained in a per-loop stack slot.

arch_bpf_timed_may_goto() uses a custom calling convention: the verifier
passes the count/timestamp stack offset in BPF_REG_AX and expects the
updated count back in the same register. The JIT call path therefore can
skip the usual 'BPF_REG_0 = C return value' move for this helper.

Acked-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: George Guo <guodongtai@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:40 +08:00
George Guo
1db6d003e9 LoongArch: BPF: Resolve per-CPU addrs for internal-only MOV
Add support for the internal-only BPF_MOV instruction that resolves the
absolute addresses of the per-CPU data from their per-CPU offsets. This
instruction is used only for internal inlining optimizations between the
BPF verifier and the JITs (e.g. inlining bpf_get_smp_processor_id() and
per-CPU map lookups).

LoongArch keeps the per-CPU offset of the current CPU in $r21 register
(a.k.a. __my_cpu_offset), so resolving a per-CPU address only requires
adding $r21 to the source register holding the per-CPU offset. Advertise
the capability via bpf_jit_supports_percpu_insn().

Acked-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: George Guo <guodongtai@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:40 +08:00
Chenguang Zhao
1fec6bbc09 LoongArch: BPF: Advertise JIT support for kptr xchg inline
The BPF verifier can lower bpf_kptr_xchg() to BPF_XCHG when the JIT
advertises ptr xchg support. With ordered amswap_db.* emission from the
previous patch, declare that LoongArch bpf JIT supports this inlining.

Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Acked-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Chenguang Zhao <zhaochenguang@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:39 +08:00
Chenguang Zhao
576412d982 LoongArch: BPF: Align value-returning atomics with LKMM
Per the Linux Kernel Memory Model, value-returning atomic RMW operations
must provide sequentially consistent ordering (a full memory barrier).
On LoongArch, plain AMO instructions and bare ll/sc loops do not satisfy
this requirement by themselves.

Update emit_atomic_rmw() to emit barrier-carrying instructions for all
value-returning BPF atomics:

 - BPF_FETCH (ADD/AND/OR/XOR): use am*_db.{b,h,w,d}
 - BPF_XCHG: use amswap_db.{b,h,w,d}
 - BPF_CMPXCHG: emit dbar 0x700 after the ll/sc loop, matching
   __WEAK_LLSC_MB in cmpxchg.h

Add the corresponding instruction encodings and emit helpers to inst.h.
Non-value-returning RMW ops (plain BPF_ADD, BPF_AND, etc.) are left as
weakly ordered, consistent with LKMM.

Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Acked-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Chenguang Zhao <zhaochenguang@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:39 +08:00
Tiezhu Yang
9fcdba3423 LoongArch: BPF: Split unconditional branch JA paths statically
In build_insn(), both 32-bit and 64-bit unconditional branch JA paths
currently share a single case block. It relies on a runtime condition
check to multiplex between the 'off' and 'imm' fields.

Since the instruction classes are already resolved at compile-time via
distinct switch-case labels, this runtime check is redundant.

Split the two paths into individual case blocks to remove the redundant
runtime check.

Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:39 +08:00
Tiezhu Yang
252ae40ba9 LoongArch: BPF: Remove dead move_imm() call in BPF_NEG path
The BPF_NEG operation is a unary operator that performs `dst = -dst`.
The current code unconditionally executes a move_imm() call before the
subtraction, generating useless JITted instructions to load data into
the temporary register `t1`. This `t1` register is never used anywhere
else in the entire BPF_NEG path.

Remove this dead `move_imm()` call to avoid useless instructions.

Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:24 +08:00
Tiezhu Yang
32a5e3eaa0 LoongArch: BPF: Remove redundant zext jumping in move_imm()
In move_imm(), when an immediate hits the 12-bit unsigned range, an
`ori rd, $zero, imm` instruction is emitted.

According to the manual, the `ori` instruction inherently performs a
logical or with zero-extended immediate operands against $zero, so the
upper 32 bits of the destination register `rd` are already 0.

However, the existing JIT code unconditionally executes `goto zext;`
after `ori`, forcing it to fallthrough into `emit_zext_32()` to clear
the upper 32 bits for 32-bit ALU operations.

Fix this redundancy by directly returning from the function inside the
`is_unsigned_imm12()` block.

Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:24 +08:00
Tiezhu Yang
434308885d LoongArch: BPF: Implement branchless conditional move for TCC
The current implementation handles combined bpf2bpf and tail calls by
checking at runtime whether REG_TCC holds a scalar count or a pointer
address via a conditional jump. This adds branch prediction overhead
in the hot path of tail call execution.

To implement branchless conditional move, use an unsigned comparison
(sltui) combined with mask instructions (maskeqz/masknez) to achieve
branchless classification and blending of incoming scalar counts and
kernel pointers in REG_TCC.

This optimization refactors the inner logic of the helper function,
unifies the offset decrement at the function entry, and removes all
runtime branching from the prologue hot path completely.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:23 +08:00
Tiezhu Yang
37d545d12f LoongArch: BPF: Refactor jump offset calculation in tail call
The old macro-based jmp_offset calculation derives the jump distance
from a stale prior-pass code stride, which can lead to wrong branch
offsets and soft lockups under extra JIT passes.

Fix this by calculating the offset directly on the absolute target:
"ctx->offset[insn + 1] - ctx->idx".

To avoid a false 16-bit range check abort during size estimation, add
a "ctx->image == NULL" guard to inject a safe dummy offset.

Cc: stable@vger.kernel.org
Fixes: cd39d9e6b7 ("LoongArch: BPF: Fix jump offset calculation in tailcall")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:23 +08:00
Tiezhu Yang
cd7e356b07 LoongArch: BPF: Move arena register slot below TCC context
Currently, the stack layout places the optional arena register slot
above the tail call counter context. When arena_vm_start is dynamically
enabled, it shifts the relative offset of the tcc_ptr slot within the
stack frame, causing hardcoded tracking macros to mismatch and leading
to memory misalignment or corruption potentially.

To fix this, move the arena register save and restore sequences below
the tail call counter context slots in both build_prologue() and the
epilogue.

Update __build_epilogue() to insert a proper offset decrement to safely
skip the unneeded tcc_ptr reading block while accurately aligning with
the relocated arena slot at the very bottom.

With this patch, the tcc_ptr slot is always positioned at a fixed
distance directly underneath the base callee-saved registers that is
independent of whether the arena features are on.

Cc: stable@vger.kernel.org
Fixes: ef54c517a9 ("LoongArch: BPF: Implement PROBE_MEM32 pseudo instructions")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:23 +08:00
Tiezhu Yang
fd3cb1bfeb LoongArch: BPF: Optimize redundant TCC loads in epilogue
The legacy epilogue implementation pops the tail call counter (TCC)
context via a redundant double-load pattern. It first decrements the
load_offset by 2 slots to fetch 'tcc_ptr', and then immediately bumps
it back up by 1 slot to load the original 'tcc' value into REG_TCC,
unnecessarily overwriting the register.

Optimize this sequence by adjusting the load_offset by only 1 slot.
This aligns the offset directly with the higher stack slot containing
the entry TCC counter (or caller state), allowing us to restore the
REG_TCC register safely with a single load.

This removes one redundant instruction from the epilogue hot path,
improves code readability, and ensures the correct TCC register context
is handed back cleanly upon normal return.

Cc: stable@vger.kernel.org
Fixes: c0fcc955ff ("LoongArch: BPF: Fix the tailcall hierarchy")
Fixes: ef54c517a9 ("LoongArch: BPF: Implement PROBE_MEM32 pseudo instructions")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:23 +08:00
Tiezhu Yang
29479b1431 LoongArch: Use current_stack_pointer in current_pt_regs()
The current implementation of current_pt_regs() relies on the compiler
__builtin_frame_address(0). This introduces an unnecessary dependency
on the frame pointer register, which forces the compiler to generate
redundant prologue and epilogue code, create a larger stack frame, and
perform redundant memory operations to preserve the frame pointer even
in functions where it is otherwise unnecessary.

Optimize this by switching to current_stack_pointer, which explicitly
maps to the hardware stack pointer register. This allows the compiler
to compute the stack alignment directly from the natively maintained
"$sp" register, completely eliminating the overhead of preserving and
restoring the frame pointer on the stack memory.

As a prominent example, this optimization improves the hot-path function
copy_thread(). A disassembly comparison of copy_thread() illustrates the
elimination of the frame pointer, the reduction of stack frame size from
48 bytes down to 32 bytes, and a more compact epilogue path:

Before:

00000000000004f0 <copy_thread>:
 4f0:   02ff4063        addi.d          $sp, $sp, -48
 4f4:   29c08076        st.d            $fp, $sp, 32
 4f8:   29c06077        st.d            $s0, $sp, 24
 4fc:   29c0a061        st.d            $ra, $sp, 40
 500:   02c0c076        addi.d          $fp, $sp, 48
 ...
 54c:   1400006e        lu12i.w         $t2, 3
 ...
 55c:   03bffdce        ori             $t2, $t2, 0xfff
 560:   00153ace        or              $t2, $fp, $t2
 564:   02fb05cd        addi.d          $t1, $t2, -319
 ...
 628:   28c0a061        ld.d            $ra, $sp, 40
 62c:   28c08076        ld.d            $fp, $sp, 32
 630:   28c06077        ld.d            $s0, $sp, 24
 634:   00150004        move            $a0, $zero
 638:   02c0c063        addi.d          $sp, $sp, 48
 63c:   4c000020        ret

After:

00000000000004f0 <copy_thread>:
 4f0:   02ff8063        addi.d          $sp, $sp, -32
 4f4:   29c04077        st.d            $s0, $sp, 16
 4f8:   29c06061        st.d            $ra, $sp, 24
 [ prologue st.d and addi.d for $fp are completely eliminated ]
 ...
 544:   1400006e        lu12i.w         $t2, 3
 ...
 554:   03bffdce        ori             $t2, $t2, 0xfff
 558:   0015386e        or              $t2, $sp, $t2
 55c:   02fb05cd        addi.d          $t1, $t2, -319
 ...
 620:   28c06061        ld.d            $ra, $sp, 24
 624:   28c04077        ld.d            $s0, $sp, 16
 628:   00150004        move            $a0, $zero
 [ epilogue ld.d for $fp is eliminated; exit path is shortened ]
 62c:   02c08063        addi.d          $sp, $sp, 32
 630:   4c000020        ret

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:14 +08:00
Tiezhu Yang
4b5b0b79d1 LoongArch: Use generic cmp_int() instead of custom cmp_3way()
Currently, the module-sections.c file defines a custom cmp_3way() macro
to perform a three-way comparison. There is already a generic cmp_int()
macro to do the same thing in linux/sort.h, thus remove the custom macro
and use the generic interface. This is similar with commit 3e17a4b443
("riscv: module: Use generic cmp_int() instead of custom cmp_3way()").

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:14 +08:00
Tiezhu Yang
18210a104b LoongArch: Expand module virtual address space to 2GB
The current 256MB module virtual address space is easily exhausted when
loading massive graphics drivers such as amdgpu along with the large
unstripped symbol tables, resulting in allocation failures of "execmem:
unable to allocate memory".

Thus, expand the module virtual address space to 2GB while keeping
the current normal code model '-mcmodel=normal', rather than using the
medium code model '-mcmodel=medium'. This approach avoids the extra
performance overhead and larger binary size of forcing every function
call into a 2-instruction sequence of 'pcaddu18i + jirl'.

Given that individual module code segments rarely exceed 128MB, most
jumps remain fast direct calls by using the bl instruction. For the
long-distance jumps exceeding the +/-128MB limit, apply_r_larch_b26()
emits PLT entries, while signed_imm_check() guarantees the run-time
safety by rejecting any out-of-bound instruction offsets.

There is still a risk that the distance between .init.text and .text of
the same module exceeds 128MB. So we divide the 2GB virtual space to be
two sub-regions: the first 256MB is for module text, and the rest is for
module data.

Cc: stable@vger.kernel.org
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:14 +08:00
Han Gao
2677f97a67 LoongArch: Add DIRECT_MAP_PHYSMEM_END definition
get_free_mem_region() and mhp_get_pluggable_range() bound their search
to DIRECT_MAP_PHYSMEM_END. LoongArch does not define it, so the fallback
in include/linux/mm.h applies: under CONFIG_SPARSEMEM_VMEMMAP it is
(1ULL << MAX_PHYSMEM_BITS) - 1, a compile-time constant that does not
adapt to the CPU's physical address space bits (cpu_pabits, probed from
CPUCFG1).

The vmemmap window only covers physical space below 2^(cpu_pabits+1)
(i.e. VMEMMAP_SIZE), so on CPUs with fewer physical address bits than
MAX_PHYSMEM_BITS the fallback allows get_free_mem_region() to return
a ZONE_DEVICE region outside the vmemmap window; vmemmap_populate() then
wraps the memmap range around and maps it into low memory, silently
corrupting the page tables. The same search also picked the top-of-
address-space region that crashed memmap_init_zone_device() with amdkfd
on Loongson-3C6000 in 6.16 [1]; the commit 2969b42c8f ("LoongArch/mm:
align vmemmap to maximal folio size") keeps that region in bounds on
current Loongson-3C6000 configs, but CPUs with smaller cpu_pabits (e.g.
the Loongson-2K series) are still affected.

Define DIRECT_MAP_PHYSMEM_END as the vmemmap-covered physical range,
(1ULL << (cpu_pabits + 1)) - 1, capped at (1ULL << MAX_PHYSMEM_BITS) - 1
under CONFIG_SPARSEMEM, similar to the commit f3336b48cf ("riscv: mm:
Define DIRECT_MAP_PHYSMEM_END").

[1] https://lore.kernel.org/amd-gfx/20250814032153.227285-1-jeffbai@aosc.io/

Cc: stable@vger.kernel.org # v6.13+
Signed-off-by: Han Gao <gaohan@iscas.ac.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:05 +08:00
Bibo Mao
2a2367d46d LoongArch: Fix acpi_package_ids[] array overflow
With LoongArch virt machine, a typical setting is one core per socket,
there will max 256 sockets (packages) on one VM. With PPTT acpi table,
array acpi_package_ids[] will be overflowed.

Here change the array size of acpi_package_ids[] with the max value of
MAX_PACKAGES and KVM_MAX_VCPUS.

Cc: stable@vger.kernel.org # 6.7+
Fixes: 4e8f58620f ("LoongArch: Retrieve CPU package ID from PPTT when available")
Reviewed-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-17 22:07:05 +08:00
Thomas Weißschuh
1f8258de23 LoongArch: Remove CONFIG_GENERIC_GETTIMEOFDAY ifdeffery
Now that there is a definition of VDSO_CLOCKMODE_CPU even if no
vDSO is built, the ugly ifdeffery can be removed.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260724-vdso-arch-clockmodes-v4-7-ddbe447be860@linutronix.de
2026-08-10 16:25:22 +02:00
Bibo Mao
9b61ad973c LoongArch: KVM: Replace kvm_err() with kvm_pr_unimpl()
Since guest kernel and ioctl() parameter from user mode is untrusted,
there may be noise kernel log output in host hypervisor with abnormal
state. Here replace kvm_err() with kvm_pr_unimpl() to reduce this kind
of noise kernel log, and there is no function change.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-10 12:21:58 +08:00
Bibo Mao
ab382eae73 LoongArch: KVM: Use internal API to deliver interrupt in kernel mode
API kvm_vcpu_ioctl_interrupt() is mainly to used to deliver interrupt
from user mode, and internal APIs kvm_queue_irq() and kvm_dequeue_irq()
are used in kernel mode.

Also move IPI inject and ack within lock protection to avoid contention
in ipi_set() and ipi_clear().

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-10 12:21:58 +08:00
Bibo Mao
81aa3a58b5 LoongArch: KVM: Fix uninitialized stack variable issue with dmsintc
Variable vector[] is declared on stack in function dmsintc_inject_irq()
and sometimes it is used without initialized. Here fix this issue.

Cc: stable@vger.kernel.org
Fixes: 03de5eecb0 ("LoongArch: KVM: Add DMSINTC inject msi to vCPU")
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-10 12:21:57 +08:00
Bibo Mao
5af8b70f56 LoongArch: KVM: Return directly when IPI address is not aligned
When IPI address is not aligned with its access size, it should return
directly in read/write operations, rather than only print a message with
WARN_ON_ONCE(). The method is the same with in kernel EIOINTC and PCHPIC
operations.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-10 12:21:57 +08:00
Bibo Mao
a068c37c71 LoongArch: KVM: Set default MAILBOX access size with 8
With IOCSR instruction emulation in function kvm_emu_iocsr(), possible
size combination is 1/2/4/8 and no other combinations. Here remove the
old default case and replace the default case with 8 in read_mailbox()
and write_mailbox().

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-10 12:21:51 +08:00
Bibo Mao
32d05564a6 LoongArch: KVM: Set vcpu->cpu before IN_GUEST_MODE is set
In function kvm_make_vcpu_request(), it will send IPI to physical CPU
when vCPU is in IN_GUEST_MODE mode. And physical CPU is set in function
kvm_check_vpid(), thus it should be called before IN_GUEST_MODE is set.
Otherwise IPI will send to wrong old physical CPU where vCPU is running.

Cc: stable@vger.kernel.org
Fixes: 2fc3bd86db ("LoongArch: KVM: Implement basic vcpu interfaces")
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-10 12:21:50 +08:00
Zeng Chi
fd4021529f LoongArch: KVM: Fix PC double advance in kernel MMIO read fast path
In the in-kernel MMIO read fast path of kvm_emu_mmio_read(),
kvm_complete_mmio_read() already advances the guest PC via update_pc().
The explicit update_pc() call right after it advances the PC a second
time, so PC moves forward by 8 bytes instead of 4, and the instruction
following the MMIO read is silently skipped.

The user space MMIO read completion path in kvm_arch_vcpu_ioctl_run()
calls kvm_complete_mmio_read() only once, and the MMIO write fast path
advances the PC exactly once as well.

Here remove the redundant update_pc() so the kernel MMIO read fast path
advances the PC by a single instruction.

Cc: stable@vger.kernel.org
Fixes: 80edf90831 ("LoongArch: KVM: Add sign extension with kernel MMIO read emulation")
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Reviewed-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-10 12:21:50 +08:00
Tao Cui
01c823f14e LoongArch: KVM: Prevent division by zero in periodic timer restore
A guest can write CSR.TCFG with the periodic bit set but a period value
of zero. When kvm_restore_timer() later enters the periodic branch,
period = cfg & CSR_TCFG_VAL evaluates to 0, causing (delta % period) to
trigger a division by zero and crash the host kernel.

Clamp the period to 1 to avoid the panic.

Fixes: a5857b9ff6 ("LoongArch: KVM: Implement vcpu timer operations")
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-08-10 12:21:50 +08:00