Commit Graph

4361 Commits

Author SHA1 Message Date
Thomas Richter
9ecc4d0338 s390/pai: Support CPU hotplug for PMU PAI
The command 'perf stat -e pai_crypto/CRYPTO_ALL/ -- <command>'
crashes the kernel when CPUs are hotplug added during that run.

Root cause is the missing allocation of per-CPU data structures
for that new CPU. The allocation is dynamic and the first
event that has task context creates such a structure for
each online CPU. This is not sufficient. CPUs may be offline
during event creation and can be set online during the
perf run time. For example commands

 # echo 0 > /sys/devices/system/cpu/cpu1/online
 # perf stat -e cycles -i -- stress-ng -t10s --matrix X
 # sleep 1
 # echo 1 > /sys/devices/system/cpu/cpu1/online

Currently without a CPU hotplug handler, that new CPU has no
per-CPU data infrastructure. The scheduler runs PMU call back
function pai_add() to install the PMU support for that CPU before
the task is being scheduled on that new CPU.
In pai_add() instructions

    mp = this_cpu_ptr(pai_root[idx].mapptr);
    cpump = mp->mapptr;

return a NULL pointer and the result is a kernel panic as variable
cpump is used inside that function.

Add CPU hotplug support for CPU add and delete and create
the necessary per-CPU data infrastructure during CPU hotplug
add processing. Same for CPU hotplug remove.
This is done when the CPU is offline to ensure the data structures
are available when CPU is made online and tasks are scheduled on it.

[hca@linux.ibm.com: fixup error path in pai_init()]

Cc: stable@vger.kernel.org # v6.19
Fixes: 582cc1b28e ("s390/pai_ext: Enable per-task and system-wide sampling event")
Fixes: 9f66572f28 ("s390/pai_crypto: Enable per-task and system-wide sampling event")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Jan Polensky <japo@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-09-08 15:53:40 +02:00
Mete Durlu
bb06e5a2a0 s390/topology: Switch to common cpu capacity code
s390 implementation of cpu capacity management infrastructure code does
not do anything different than its common code counterpart. Switch to
common code functions and remove the smp_cpu_*_capacity() functions.
Make s390 code better align with other architectures which utilize
cpu_capacity. No functional changes.

Allow cpu_capacity attributes inside sysfs to accurately reflect cpu
capacity.
ex:

$ cat /sys/devices/system/cpu/cpu0/polarization
vertical:high
$ cat /sys/devices/system/cpu/cpu0/cpu_capacity
1024

$ cat /sys/devices/system/cpu/cpu40/polarization
vertical:low
$ cat /sys/devices/system/cpu/cpu40/cpu_capacity
128

Prior to commit 6bceea7a1e ("arch_topology: Relocate cpu_scale to
topology.[h|c]") cpu_capacity attribute was only available to the common
arch_topology driver's users. Reflect the correct values to the newly
made available attributes.

Signed-off-by: Mete Durlu <meted@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-08-31 16:25:39 +02:00
Ilya Leoshkevich
b00c10948f s390/cpacf: Unpoison instruction results
Stop KMSAN from complaining about CPACF outputs being uninitialized.

Do not unpoison variable-length parameter blocks: mapping function
codes (like CPACF_KIMD_SHA_256) to lengths will be ugly. So let the
callers do this once the need arises.

Also do not touch cpacf_kma(): this wrapper does not handle cc 1 and
cc2 at the moment and has to be reworked.

Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-08-31 16:25:38 +02:00
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
66ec24c5d7 s390 updates for 7.3 merge window
- Add a cpuidle driver with polling and enabled wait states using the
   existing CPU idle infrastructure and idle governor to improve latency
   for frequent sleep/wakeup cycles. Remove the obsolete tick delay
   heuristic and generic arch_needs_cpu() hook. Add the corresponding
   driver entry to MAINTAINERS
 
 - Add kCFI support using the generic support provided by Clang
 
 - Enable Clang CONTEXT_ANALYSIS for various architecture code and for
   char, PCI, CIO and virtio drivers. Add required lock annotations,
   exclude unsupported mm helpers and remove conditional PCI locking
 
 - Fix secure storage access exception handling and reintroduce
   DCACHE_WORD_ACCESS previously removed as a workaround
 
 - Fix cpum_cf perf crashes when CPUs are brought online while per-task
   events are active. Allocate and remove per-CPU counter data from CPU
   hotplug callbacks
 
 - Fix a deadlock when an s390dbf debug area is unregistered while one
   of its debugfs files is being written to
 
 - Fix MVIY_PERCPU() with binutils older than 2.39, where an assembler
   macro silently omitted an instruction needed to repair interrupted
   operations after CPU migration
 
 - Remove/replace cond_resched() calls which are no-ops with the supported
   s390 preemption models
 
 - Fix AP queue depth and maximum message length decoding according to
   the architecture. Current hardware is not affected, but future hardware
   could report values which were handled incorrectly
 
 - Reflect the configured CPU state in cpu_enabled_mask so deconfigured
   CPUs are not presented as available for onlining
 
 - Restore the vDSO GNU_EH_FRAME program header which was lost when the
   build switched to direct linker invocation, and mark it read-only
 
 - Add SCLP action qualifiers used by Spyre for card initialization,
   recoverable error and telemetry reporting
 
 - Move KMSAN interrupt flag helpers out of line to fix
   -Wstatic-in-inline build warnings
 
 - Use level-specific page table entry accessors for hugetlb entries and
   ptep_get() when accessing crashed kernel memory in kdump
 
 - Make forced AP bus rescans killable so that a user process blocked
   behind an ongoing scan can still be terminated with SIGKILL
 
 - Rework pkey ioctl error paths to remove duplicated cleanup code and
   avoid freeing error pointers
 
 - Allow the protected guest SWIOTLB buffer to be allocated outside the
   first 2GB. Also enable dynamic SWIOTLB growth and the coherent atomic
   pool fallback to improve I/O behavior when the initial pool is exhausted
 
 - Add program check statistics and spinlock contention tracepoints.
   Increase the lockdep chain capacity to keep lockdep enabled for complex
   code paths such as btrfs
 
 - Simplify IPL, trap and syscall code and remove the obsolete unistd_32.h
   generation entry
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEE3QHqV+H2a8xAv27vjYWKoQLXFBgFAmqLHuoACgkQjYWKoQLX
 FBhf2Qf+JlV+jQM1Lvn/Dj16vuQ77a4aP5C/OnLGMaTrrzbX420qU04yvC96v2Xu
 ux01aDU9VakonE74IT0NmrNo1VDUk8nSvIWUTB6GH7KvK76VEZN5Kkyn8TmeRmE0
 bZ0Fg7MgnhwdYijFDiX9w4rLyirwxs7vkScdJdJd0iKEdoZHXojGSjPDvmSpXght
 FgCszt+YOqu9MMf9B5oGAl+P40mgPTlm6M+ygoe2dX7qPQBUHLbDPTgZiWnKdXi2
 LPx0QPEha921ePDWrWz2HEqNetMfwGl12iertXddf1uzuK6LLObi0M5QrGw/ZbOy
 UJFM+AjFekTQyZPSunD4NWyCjglqrA==
 =XF7Y
 -----END PGP SIGNATURE-----

Merge tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

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

 - Add kCFI support using the generic support provided by Clang

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

* tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (59 commits)
  s390/percpu: Fix MVIY_PERCPU() with older binutils
  s390/debug: Fix deadlock during unregister
  s390/cpum_cf: Handle CPU hotplug via prepare/dead callbacks
  s390: Enable CONTEXT_ANALYSIS for various directories
  s390/mm: Add __context_unsafe() attribute to gmap helper functions
  s390/mm: Add __context_unsafe() attribute to do_secure_storage_access()
  s390/sysinfo: Add context analysis attributes
  s390/irqflags: Add out-of-line definitions of arch_local_irq_*() for KMSAN
  s390/virtio: Enable CONTEXT_ANALYSIS
  s390/cio: Enable CONTEXT_ANALYSIS
  s390/vfio_ccw: Add __must_hold() attribute to vfio_ccw_sch_quiesce()
  s390/pci: Enable CONTEXT_ANALYSIS
  s390/pci: Rework __zpci_event_availability() to remove conditional locking
  s390/pci: Rework __zpci_event_error() to remove conditional locking
  s390/char: Enable CONTEXT_ANALYSIS
  s390/con3215: Add __must_hold() attribute to raw3215_make_room()
  s390/ap: Fix MAPML computation
  s390/cio: Remove cond_resched() calls
  s390: Remove cond_resched() calls
  KVM: s390: Remove cond_resched() calls
  ...
2026-08-23 10:26:44 -07:00
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
a625b2a387 VFIO updates for v7.3-rc1
- Add nv_falcon vfio selftest driver.  The Falcon is a general-purpose
    microcontroller embedded within NVIDIA GPUs, presenting a relatively
    simple DMA programming interface.  This adds another selftest target
    for vfio-pci with real DMA transfers. (Rubin Du, Alex Williamson)
 
  - Add allocation assertion helpers to vfio selftests and use them to
    avoid variable length arrays and the compiler errors they generate.
    (Alex Mastro)
 
  - Fix use-after-free hazard where an init path error in MSI support
    leaves a stray pointer that can later be reused or double-freed.
    (Xiang Mei)
 
  - Fix previous refactor of PCI BAR mappings to honor non_mappable_bars
    flag, which otherwise generates a warning when trying to pci_iomap()
    a 256TiB BAR on ISM devices on s390. (Farhan Ali)
 
  - Add igb vfio selftest driver.  Like nv_falcon, this provides another
    target for DMA testing with vfio selftests, but importantly this
    driver supports both physical 82576 NICs and the emulation model in
    QEMU.  This therefore enables a vfio selftest vector with no physical
    hardware requirements. (Josh Hilke, Alex Williamson)
 
  - Mark selftest fixture objects __maybe_unused to accommodate builds
    with clang -Wunused-but-set-global. (David Matlack)
 
  - Add error recovery for vfio-pci devices on s390x.  This expands
    devices which expose the existing error eventfd and introduces a
    device feature for reporting firmware defined error state
    information to the user, allowing recovery through hypervisor
    channels. (Farhan Ali)
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEQvbATlQL0amee4qQI5ubbjuwiyIFAmqE1t4RHGFsZXhAc2hh
 emJvdC5vcmcACgkQI5ubbjuwiyJyRg//UQg1EnIu18XdTIMWwFDOIeeJBj+Vm/KK
 FzlS4Fsp2jw3qIXTX9KbxU+Bxx8TyHo9h7IhBYSPfaLAjoWLvCllu/HTScU1zumL
 +oXiiSLKcqX3q63c1i3U7/QJNgBeRf7CAnwaCXe6Sd57UL2JT+lcURJvEYYj9KRG
 yWlsnEnw0kKH4w1rujh3fRcDx31GJf6RmxCK4RqIDyMk7YRfVExD3AOm0GjBN+0N
 6YyW0/jF7cy0OgAr1DN5EZocyWJX70roWBSFPa2jO3q9UwDomexQDvH26x5VucDG
 6kK1qHHPcW2P5Rel3ggEzKEo3C9bjC1vCqHGT7Vf/5MZMtDekJ82L31jd8gxCodD
 q9dnNVXJAScQV38GrIG04FXzjyyB1dnUY6lm2wiZsEhsen2Eot1ZcWAVxHZ8zqdZ
 hE6mjA2fCgDC5OUrHj7KhGD1Ya4SZRs0qjuW32GLnv7BoGGaec4x6nLDJKdB4V+y
 n26NjoutQdhwj+LjgOZNXb9K3dVgayMvzzDgBV9z6i574R5/A9EjjmkeVUAnfie1
 UfW7uod3gCJq9Yzo58GnHLRR7jDZ0miXzq2iZ6SM8FpuHP52Eq0Q7GPs7PHs1coO
 xD0ONL6hJav3ZEZEJLtUhCSop7T7CVv3JsSPc6rJo8b5AyhIf7ZZQ8OEOqhiN4uX
 ixBRMTzcYkw=
 =hR5/
 -----END PGP SIGNATURE-----

Merge tag 'vfio-v7.3-rc1' of https://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Add nv_falcon vfio selftest driver.

   The Falcon is a general-purpose microcontroller embedded within
   NVIDIA GPUs, presenting a relatively simple DMA programming
   interface.

   This adds another selftest target for vfio-pci with real DMA
   transfers (Rubin Du, Alex Williamson)

 - Add allocation assertion helpers to vfio selftests and use them to
   avoid variable length arrays and the compiler errors they generate
   (Alex Mastro)

 - Fix use-after-free hazard where an init path error in MSI support
   leaves a stray pointer that can later be reused or double-freed
   (Xiang Mei)

 - Fix previous refactor of PCI BAR mappings to honor non_mappable_bars
   flag, which otherwise generates a warning when trying to pci_iomap()
   a 256TiB BAR on ISM devices on s390 (Farhan Ali)

 - Add igb vfio selftest driver.

   Like nv_falcon, this provides another target for DMA testing with
   vfio selftests, but importantly this driver supports both physical
   82576 NICs and the emulation model in QEMU.

   This therefore enables a vfio selftest vector with no physical
   hardware requirements (Josh Hilke, Alex Williamson)

 - Mark selftest fixture objects __maybe_unused to accommodate builds
   with clang -Wunused-but-set-global (David Matlack)

 - Add error recovery for vfio-pci devices on s390x.

   This expands devices which expose the existing error eventfd and
   introduces a device feature for reporting firmware defined error
   state information to the user, allowing recovery through hypervisor
   channels (Farhan Ali)

* tag 'vfio-v7.3-rc1' of https://github.com/awilliam/linux-vfio:
  vfio/pci: Remove the pcie check for VFIO_PCI_ERR_IRQ_INDEX
  vfio-pci/zdev: Add a device feature for error information
  s390/pci: Store PCI error information for passthrough devices
  PCI/MSI: Enable memory decoding before restoring MSI-X messages
  PCI: Fail FLR when config space is inaccessible
  PCI: Avoid saving config space state if inaccessible
  PCI: Allow per function PCI slots to fix slot reset on s390
  PCI: Introduce PCI_SLOT_PLACEHOLDER constant for slot_nr placeholder value
  selftests: harness: Mark test fixture objects __maybe_unused
  vfio: selftests: Retry on EAGAIN during device reset
  vfio: selftests: igb: Add driver for Intel 82576 device
  vfio: selftests: Add helpers to re-enable interrupts
  vfio/pci: Avoid mapping BARs for devices with non-mappable BARs
  vfio/pci: clear vdev->msi_perm after freeing it on init failure
  vfio: selftests: Avoid VLAs
  vfio: selftests: Add allocation assert helpers
  vfio: selftests: Add NVIDIA Falcon driver for DMA testing
  vfio: selftests: Allow drivers without send_msi() support
  vfio: selftests: Add generic PCI command register helpers
  vfio: selftests: Add memcpy chunking to vfio_pci_driver_memcpy()
2026-08-20 16:57:59 -07:00
Linus Torvalds
030c9f813b Treewide timer related cleanups:
- Remove the leftover CLOCK_TICK_RATE which has been scheduled for
     removal more than a decade ago along with some now empty asm/timex.h
     files.
 
   - Consolidate delay timer calibration
 
     The construct of having a define in a header requires that
     architectures provided asm/timex.h for no reason. Also the function
     name for reading the delay timer is confusing at best.
 
     Use a config switch to enable that functionality and rename the
     function to delay_read_timer() to make the purpose clear.
 
     This removes some more now empty asm/timex.h files as well.
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCgAuFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmqCuTUQHHRnbHhAa2Vy
 bmVsLm9yZwAKCRCmGPVMDXSYoU77EACd8W1/bIYBW1XtlNMrc5PLS0wCIG55D793
 03ebljTfGGfrNcPJIXHXT7yQLaUF7me/4d3xv1SCbDOjv2dR+Ma5Bhq7DpgIaNaj
 xUTvKT+mEsSXbh+sFd/2rrqQ3fPAfDiobDA3yEnuV/8zfCqtrFf5dGRAvobw3yl8
 kdGSp3PCF5O/0ynpqUnJ1/fdWft2wNA8B0MT322MU4X+DVvTWv4wxDGStA8mnVv/
 x6kCNnCe2KRIwi6pZBhodjhl+BYHdMh6c0nJOrmTNKyrfcUMKbnttyfyvAKX9uPZ
 L5XDVLy8n8iC7P1FZMGipAylGI4abhQgDz6RXAwEygjC+S/ppjc7HFcx17TdzKYa
 0BzgWOsdDbbtorB4Ro24x6aNBW2ReN8UJsNSH2ZlmdtHH861uOsAJCfCkpCLMdRF
 Ysbj6gFSn6sf9l0TyPlJds53r5B1L4CNOM4UKztNRoZ944wvTD+J78homvmjlF75
 JcfQD7YvDEqgolfZNkmWoMJe5HU9pZk0mcYxpnj/Xa3HCm2M7qE8iWq4EesCxAXW
 C+IBpTVaZyf2h1jo47ZLeYYFXXSz3F542jmuC/EiLNFNT8MEFtG59+1x1KbcaHlh
 hmi72YncoW2QES6yzjCNyuVq687A3bKs+bCkKVXkn5vlFodilnLgJUZ2sK5yIAU7
 hI1IpZLl1A==
 =V0WX
 -----END PGP SIGNATURE-----

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

Pull treewide timer related cleanups from Thomas Gleixner:

 - Remove the leftover CLOCK_TICK_RATE which has been scheduled for
   removal more than a decade ago along with some now empty asm/timex.h
   files.

 - Consolidate delay timer calibration

   The construct of having a define in a header requires that
   architectures provided asm/timex.h for no reason. Also the function
   name for reading the delay timer is confusing at best.

   Use a config switch to enable that functionality and rename the
   function to delay_read_timer() to make the purpose clear.

   This removes some more now empty asm/timex.h files as well.

* tag 'timers-cleanups-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  calibrate: Rework delay timer calibration
  treewide: Remove CLOCK_TICK_RATE
  x86: Use PIT_TICK_RATE instead of CLOCK_TICK_RATE
2026-08-18 15:58:29 -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
dfa35434d7 Locking updates for v7.3:
Futexes:
 
  - Use runtime constants for futex_hash computation
    (K Prateek Nayak, Peter Zijlstra)
 
  - Optimise the size check get_futex_key() (Sebastian Andrzej Siewior)
 
  - Avoid private hash use-after-free on final put (Felix Hoffmann)
 
  - Tell kmemleak we're not leaking __futex_queues (Peter Zijlstra)
 
 Rust integration updates:
 
  - Implement refcounted interrupt disable and SpinLockIrq for Rust
    (Boqun Feng, Heiko Carstens, Joel Fernandes, Lyude Paul)
 
  - Rust sync: add helpers for mb, dma_mb and friends;
    add generic memory barriers and use LKMM atomics
    instead of Rust atomics in the revocable code (Gary Guo)
 
  - Add abstraction and integrate synchronize_rcu() (Philipp Stanner)
 
 Lock debugging:
 
  - Add qspinlock contended_release tracepoint
    (Dmitry Ilvokhin, Peter Zijlstra)
 
  - Enable the printing of held locks of remote running tasks and print
    task CPU (Ingo Molnar)
 
  - percpu-rwsem: Annotate intentional data race in readers_active_check()
    (Sun Shaojie)
 
 Misc fixes and updates by Boqun Feng, Peter Zijlstra, Fangrui Song,
 Naveen Kumar Chaudhary and Thomas Huth.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmqC2KMRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1gNwg//awvTQONfhPanAyTgl7CLDSlMSHdqmlyh
 Ue0/Q8Ef1Cy4jwXY2FE2A0b1VcM6cGpDPoryVdg/wMdUXRNwinzAEXmxIkRy9kve
 4LybrZwDShgLxJ7pJ6KKhgjgDiat8EdYmOwCBEE3LnP7AYhkAb8BFetA3YZJvzPa
 KfA2BRYCgvBTid6yOAuXWm55Ev92AczOBamBzTxCadcaDGtNGXtQO6LfnqiQDOav
 X5tVoANBeaQtSs1+LxE41WdNOiRoBuy0IFFvXtZRal6PZYuGGmZ5tbQvscD099em
 haVwQyzDHQrqzglv71M0KRTXvYzdGveMRg/Au1SQnuLO3V6Vd5rMQ1g7I2M9Ln0f
 Pg+tlRvQ77mLoqcgrtl0W/u0fRR4eDkiJ1pmG+98oniPwau23RdbFhC0vKFz3ikF
 WHMgk3/9TcULylgF1Tj6QLmNrBY3Vx8LBdsFjhflEw7bG4cW42D91npmXIiEDE6K
 tJc9CcaVdyE75o59z2Dtjj+qQVBlNPlfKQFXFL7p3jU/gFw2SzYuqon66X3kGmr0
 mKJ9UNJdkLdiCjxS/QiMcDeYhwJksJqxFBkH50z3Kzmo84JsSpUFkoa6GM4aSiGn
 HEwgC0Q7oOXVNIKUBYk5QaRW0HSk55hbsX2TWkvpeBYkE1zXshVZCCmgpaTSJgb5
 oFmiwrGfUjo=
 =slqC
 -----END PGP SIGNATURE-----

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

Pull locking updates from Ingo Molnar:
 "Futexes:

   - Use runtime constants for futex_hash computation (K Prateek Nayak,
     Peter Zijlstra)

   - Optimise the size check get_futex_key() (Sebastian Andrzej Siewior)

   - Avoid private hash use-after-free on final put (Felix Hoffmann)

   - Tell kmemleak we're not leaking __futex_queues (Peter Zijlstra)

  Rust integration updates:

   - Implement refcounted interrupt disable and SpinLockIrq for Rust
     (Boqun Feng, Heiko Carstens, Joel Fernandes, Lyude Paul)

   - Rust sync: add helpers for mb, dma_mb and friends; add generic
     memory barriers and use LKMM atomics instead of Rust atomics in the
     revocable code (Gary Guo)

   - Add abstraction and integrate synchronize_rcu() (Philipp Stanner)

  Lock debugging:

   - Add qspinlock contended_release tracepoint (Dmitry Ilvokhin, Peter
     Zijlstra)

   - Enable the printing of held locks of remote running tasks and print
     task CPU (Ingo Molnar)

   - percpu-rwsem: Annotate intentional data race in readers_active_check()
     (Sun Shaojie)

  Misc fixes and updates by Boqun Feng, Peter Zijlstra, Fangrui Song,
  Naveen Kumar Chaudhary and Thomas Huth"

* tag 'locking-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  rust: sync: Introduce SpinLockIrq::lock_with() and friends
  rust: sync: Add SpinLockIrq
  rust: sync: Use super::* in spinlock.rs
  rust: helper: Add spin_{un,}lock_irq_{enable,disable}() helpers
  rust: Introduce interrupt module
  s390/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS
  arm64: sched/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS
  preempt: Introduce HAS_SEPARATE_PREEMPT_RESCHED_BITS
  sched: Avoid signed comparison of preempt_count() in __cant_migrate()
  sched: Remove the unused preempt_offset parameter of __cant_sleep()
  locking: Switch to _irq_{disable,enable}() variants in cleanup guards
  irq: Add KUnit test for refcounted interrupt enable/disable
  irq,spin_lock: Add counted interrupt disabling/enabling
  openrisc: Include <linux/cpumask.h> in smp.h
  preempt: Introduce __preempt_count_{sub,add}_return()
  preempt: Introduce HARDIRQ_DISABLE_BITS
  preempt: Track NMI nesting to separate per-CPU counter
  futex: Tell kmemleak we're not leaking __futex_queues
  x86/paravirt: Trace contended_release on unlock
  tracing/lock: Use TRACE_EVENT_FN() for contended_release
  ...
2026-08-18 13:07:17 -07:00
Farhan Ali
fa63a2e3f9 vfio-pci/zdev: Add a device feature for error information
For zPCI devices, we have platform specific error information. The platform
firmware provides this error information to the operating system in an
architecture specific mechanism. To enable recovery from userspace for
these devices, we want to expose this error information to userspace. Add a
new device feature to expose this information.

Userspace needs to be provide a buffer of fixed size. This size is provided
to userspace via the VFIO_DEVICE_INFO_CAP_ZPCI_BASE capability.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Link: https://lore.kernel.org/r/20260630165553.725-3-alifm@linux.ibm.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
2026-08-13 11:36:55 -06:00
Farhan Ali
9f240376d0 s390/pci: Store PCI error information for passthrough devices
For a passthrough device we need co-operation from user space to recover
the device. This would require to bubble up any error information to user
space.  Let's store this error information for passthrough devices, so it
can be retrieved later.

We can now have userspace drivers (vfio-pci based) on s390x. The userspace
drivers will not have any KVM fd and so no kzdev associated with them. So
we need to update the logic for detecting passthrough devices to not depend
on struct kvm_zdev.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Link: https://lore.kernel.org/r/20260630165553.725-2-alifm@linux.ibm.com
Signed-off-by: Alex Williamson <alex@shazbot.org>
2026-08-13 10:44:46 -06:00
Karl Mehltretter
101782f894 s390/percpu: Fix MVIY_PERCPU() with older binutils
Commit a737737cdb ("s390/percpu: Infrastructure for more efficient
this_cpu operations") introduced MVIY_PERCPU(), which stringifies
arguments that are already C string literals. This generates an
assembler macro invocation with whitespace-separated quoted arguments:

  GEN_MVIY "459712" "%r3"

GNU as versions prior to binutils 2.39 drop the separating whitespace
between quoted macro arguments during input scrubbing. They
consequently parse the invocation as a single argument and emit
repeated warnings:

  Warning: missing closing `"'

The .ifc in GEN_MVIY never matches and GNU as exits successfully
without emitting the mviy instruction. As a result, the interrupted
per-CPU sequence is not marked in lowcore and the exception return
path cannot repair the per-CPU address register after migration.

All MVIY_PERCPU() callers pass C string literals. Use them directly
and separate the assembler macro arguments with an explicit comma. The
resulting invocation is:

  GEN_MVIY 459712, %r3

This form is unambiguous for GNU as and LLVM's integrated assembler.
This behavior was fixed in GNU as from binutils 2.39, but Linux
supports binutils 2.30.

Fixes: a737737cdb ("s390/percpu: Infrastructure for more efficient this_cpu operations")
Cc: stable@vger.kernel.org
Assisted-by: Codex:gpt-5.6-sol
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-13 16:56:45 +02:00
Steffen Eiden
a07276d5d1 KVM: s390: gmap: Make storage keys optional
Guard guest storage key handling behind `KVM_S390_MANAGES_S390_GUEST`.
This enables other KVM implementations to use gmap without implementing
storage key infrastructure. Define KVM_S390_MANAGES_S390_GUEST to 1 for
KVM hosts managing s390 guests (in kvm_host_s390.h). A KVM
implementation not implementing those features must define
KVM_S390_MANAGES_S390_GUEST to 0 in its kvm_host_<guest_arch>.h.

No functional changes besides the new guard.

Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 08:55:09 +02:00
Steffen Eiden
9881bf55c5 KVM: s390: Move PGM code definitions to asm/kvm_host.h
Move PGM code definitions from kvm_host_s390.h (back) to the generic
kvm_host.h. These definitions are needed by multiple KVM implementations
and should be in a shared location.

No functional change.

Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 08:54:59 +02:00
Steffen Eiden
3da0913c69 KVM: s390: Move kvm_host definitions to kvm_host_s390
Rename kvm_host.h to kvm_host_s390.h and kvm_host_types.h to
kvm_host_s390_types.h to distinguish s390-specific KVM definitions
from the generic kvm_host.h that will be used for shared definitions.

No functional change.

Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-13 08:54:51 +02:00
Christian Borntraeger
d873515be0 Merge remote-tracking branch 'kvms390/master' into 'kvms390/next' 2026-08-12 18:15:44 +02:00
Ilya Leoshkevich
3f7c9f9c36 s390/irqflags: Add out-of-line definitions of arch_local_irq_*() for KMSAN
Inline KMSAN arch_local_irq_*() definitions run afoul of
-Wstatic-in-inline. Move them out-of-line. Make sure decompressor and
non-GPL modules see the out-of-line definitions.

Cc: Boqun Feng <boqun@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202607131219.euJHPSJ5-lkp@intel.com/
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Fixes: 1b301f5f28 ("s390/irqflags: do not instrument arch_local_irq_*() with KMSAN")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-11 16:42:18 +02:00
Christian Borntraeger
546dde823a KVM: s390: Fix memory corruption by not reinjecting CK machine checks
Channel-subsystem damage machine checks are for the host channel
subsystem. The guest channel subsystem is emulated in the userspace VMM.
There is no point in forwarding such machine checks into the guest.

This also simplifies the machine check reinjection and avoids kfree of a
stack variable as reported by sashiko.  There might be still machine
checks that have the ck bit set with another bit (like instruction
damage), mask out the CK bit in s390_backup_mcck_info(), like the CP and
ED bits already are.

Fixes: 4d62fcc0b6 ("KVM: s390: Inject machine check into the guest")
Cc: stable@vger.kernel.org
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260806145835.31818-1-borntraeger@linux.ibm.com>
2026-08-11 10:45:56 +02:00
Christoph Schlameuss
3105276cef KVM: s390: vsie: Create constant SCB_ALIGNMENT_SHIFT
Create a simple constant for the SCB alignment shift.

Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-10 14:22:56 +02:00
Heiko Carstens
3484440a7b s390/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS
Convert s390's preempt_count to 64 bit, and change the preempt
primitives accordingly.

[boqun: Apply the corrected comment for asm block]
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Boqun Feng <boqun@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260804161447.84806-13-boqun@kernel.org
2026-08-10 10:50:20 +02:00
Boqun Feng
4ad87eee54 preempt: Introduce __preempt_count_{sub,add}_return()
In order to use preempt_count() to track the interrupt disable nesting
level, __preempt_count_{add,sub}_return() are introduced, as their names
suggest, these primitives return the new value of the preempt_count()
after changing it. The following example shows the usage of it in
local_interrupt_disable():

	// increase the HARDIRQ_DISABLE bit
	new_count = __preempt_count_add_return(HARDIRQ_DISABLE_OFFSET);

	// if it's the first-time increment, then disable the interrupt
	// at hardware level.
	if ((new_count & HARDIRQ_DISABLE_MASK) == HARDIRQ_DISABLE_OFFSET) {
		local_irq_save(flags);
		raw_cpu_write(local_interrupt_disable_state, flags);
	}

Having these primitives will avoid a read of preempt_count() after
changing preempt_count() on certain architectures.

Signed-off-by: Boqun Feng <boqun@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # s390
Link: https://patch.msgid.link/20260804161447.84806-4-boqun@kernel.org
2026-08-08 22:44:06 +02:00
Heiko Carstens
97d86fc847 KVM: s390: Remove cond_resched() calls
Since [1] cond_resched() is a no-op on s390. Remove all calls.

This also entirely removes uv_call_sched() and replaces all call sites
with uv_call(), since both functions are identical after the removal
of cond_resched().

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

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:16:54 +02:00
Peter Zijlstra
e11733826f s390/crypto: Replace cond_resched() with msleep(1)
With [1] cond_resched() is always compiled away and becomes a no-op.

The comments for all cond_resched() calls in crypto code however indicate
that the current process should be scheduled away to avoid instant
re-invocation of a callback. This is not what cond_resched() would do or
did.

Instead of just removing the cond_resched() calls, replace them with
msleep() calls, as suggested by Holger Dengler. This forces the current
task to be scheduled away (sleeps) like originally intended.

Holger provided information why this intended [2]:
"
Let me give a bit of background here: The protected key can only get
invalid, if the Linux instance (z/VM or KVM guest) is moved to another
hypervisor on a different machine (aka life guest relocation). In such a
case, the crypto accelerator card and the host has to exchange the "real
key", which is wrapped by the host and handed back to the guest as the
re-newed protected key. Unfortunately there is no asynchronous trigger
on completion, you have to re-try (and maybe get another "in progress"
return).

And as if that weren't bad enough, if this key exchange between card and
host is the first one, card and host has to instantiate a secure
communication channel (including a key exchange for the transport layer).
"

[1] commit 7dadeaa6e8 ("sched: Further restrict the preemption modes")
[2] https://lore.kernel.org/all/39570813-27b0-40f9-89c5-8e2dce05e2f0@linux.ibm.com/
[3] https://lore.kernel.org/all/20260731084027.GE776954@noisy.programming.kicks-ass.net/

[hca@linux.ibm.com: took Peter's patch [3] and provided commit message]

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:16:54 +02:00
Heiko Carstens
227b4e108a s390/bpf: Add kCFI support
This is the s390 variant of commit 710618c760 ("arm64/cfi,bpf: Support
kCFI + BPF on arm64").

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-08-05 15:16:54 +02:00
Kiryl Shutsemau (Meta)
c0ffe79eed mm: rename uffd-wp PTE accessors to uffd
Userfaultfd RWP will reuse the uffd-wp PTE bit to mark access-tracking
PTEs, alongside the write-protected ones it already marks.  The bit's
meaning now depends on the VMA flag (WP or RWP), not on its name.

Rename the kernel-internal names that describe the bit:

  - pte/pmd/huge_pte accessors (and swap variants)
  - pgtable_supports_uffd() capability query
  - SCAN_PTE_UFFD khugepaged enum

The ftrace string emitted by mm_khugepaged_scan_pmd for this enum is
kept as "pte_uffd_wp" so existing trace-based tooling keeps matching.

Pure mechanical rename -- no behavior change.

Link: https://lore.kernel.org/20260708111417.173443-4-kirill@shutemov.name
Signed-off-by: Kiryl Shutsemau <kas@kernel.org>
Assisted-by: Claude:claude-opus-4-6
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: James Houghton <jthoughton@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04 19:18:36 -07:00
Kiryl Shutsemau (Meta)
c6f11553c0 mm: decouple protnone helpers from CONFIG_NUMA_BALANCING
Patch series "userfaultfd: working set tracking for VM guest memory", v10.

This series 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.


This patch (of 15):

pte_protnone() and pmd_protnone() detect present-but-inaccessible page
table entries.  This capability is useful beyond NUMA balancing -- for
example, userfaultfd working set tracking uses protnone PTEs to track page
access without unmapping pages.

Introduce CONFIG_ARCH_HAS_PTE_PROTNONE to decouple the protnone PTE
infrastructure from CONFIG_NUMA_BALANCING.  The six architectures that
support protnone PTEs (x86_64, arm64, powerpc, s390, riscv, loongarch) now
select this option, and CONFIG_NUMA_BALANCING depends on it.

No functional change -- the same set of architectures continues to have
working protnone support, but the infrastructure is now available
independently of NUMA balancing.

Link: https://lore.kernel.org/20260708111417.173443-1-kirill@shutemov.name
Link: https://lore.kernel.org/20260708111417.173443-2-kirill@shutemov.name
Signed-off-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Assisted-by: Claude:claude-opus-4-6
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: James Houghton <jthoughton@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-08-04 19:18:36 -07:00
Claudio Imbrenda
496e0f706b KVM: s390: Fix unlikely NULL gmap dereference
When creating a new vCPU, kvm_vm_ioctl_create_vcpu() will call
kvm_arch_vcpu_postcreate() after the file descriptor for the new vCPU
has been created. The new file descriptor has not been returned yet,
but a malicious userspace program could try to guess it.

If a malicious userspace program manages to start the newly created vCPU
before kvm_arch_vcpu_postcreate() is called, __vcpu_run() will try to
dereference vcpu->arch.gmap and trigger a NULL pointer dereference.

Fix this by adding a new field to struct kvm_vcpu_arch to keep track of
the initialization status of the vCPU. Refuse to run a vCPU that is not
fully initialized.

Fixes: dafd032a15 ("KVM: s390: move vcpu specific initalization to a later point")
Fixes: e38c884df9 ("KVM: s390: Switch to new gmap")
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260803124040.126471-2-imbrenda@linux.ibm.com>
2026-08-03 15:39:05 +02:00
Niklas Schnelle
753b3873ce s390/sclp: Allow SCLP Action Qualifiers for Spyre card status reporting
Add SCLP Action Qualifiers used by the Spyre stack for reporting of the
card's initialization status, recoverable errors, and telemetry data.

Co-developed-by: Andreas Krebbel <krebbel@linux.ibm.com>
Signed-off-by: Andreas Krebbel <krebbel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-31 13:31:30 +02:00
Finn Callies
bdce129e44 s390/ap: Fix queue depth field length
The queue depth field is defined as a 5 bit field in the Z architecture
instead of a 4 bit field.

The queue depth (qd) can be in range 0-31 and is reported in bits 59-63
of the TAPQ response. Currently this has no effect as all CEX generations
report a queue depth of 7, which fits into 4 bits. However, future CEX
generations reporting a value >15 would not be properly reflected by the
ap bus and therefore all user space applications relying on it.

Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Finn Callies <fcallies@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-31 13:31:30 +02:00
Usama Arif
d547b10017 mm: rename ARCH_ENABLE_THP_MIGRATION to ARCH_HAS_PMD_SOFTLEAVES
CONFIG_ARCH_ENABLE_THP_MIGRATION gates PMD-level migration entries. 
PMD-level device-private entries use the same migration mechanism and
therefore require the same architecture support.

Upcoming PMD-level swap entries can use the same PMD softleaf helpers
without depending on page migration, so rename the architecture gate to
CONFIG_ARCH_HAS_PMD_SOFTLEAVES.  This describes the PMD entry capability
rather than one current user of it.

This is a pure rename: the set of selecting architectures (x86, arm64,
s390, riscv, loongarch, and powerpc on PPC_BOOK3S_64) and the gating
semantics are unchanged.

No functional change intended.

Link: https://lore.kernel.org/20260706114320.1643046-7-usama.arif@linux.dev
Signed-off-by: Usama Arif <usama.arif@linux.dev>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <baoquan.he@linux.dev>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Kiryl Shutsemau <kas@kernel.org>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-30 19:40:25 -07:00
Heiko Carstens
656db30220 s390: Add support for DCACHE_WORD_ACCESS (again)
Implement load_unaligned_zeropad() and enable DCACHE_WORD_ACCESS to
speed up string operations in fs/dcache.c and fs/namei.c.

With the secure storage access exception cases addressed, add support
for DCACHE_WORD_ACCESS again.

Tested-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-30 00:29:11 +02:00
Heiko Carstens
aab0734094 KVM: s390: pv: Use VM_SPARSE area for guest variable storage area
The guest variable storage area is allocated with vmalloc and then
donated to the ultravisor. Any kernel access to that area will result
in a secure storage access exception (aka fault).

This is a problem if such a memory area is read via /proc/kcore. This
causes an exception via vread_iter() and results in an unexpected short
read. Avoid this by allocating a custom VM_SPARSE area. If such an area
is read, vread_iter() returns zeroes for the entire area.

Note that the function which frees the area does not update ptes. This
is intentional to allow for deferred / lazy pte updates and TLB flushing
like the generic vfree() code is doing that. See vunmap_pte_range().

This assumes that s390 will gain full support for lazy_mmu_mode_enable()
and lazy_mmu_mode_disable() in the future, since as of now the used
ptep_get_and_clear() in vunmap_pte_range() does indeed invalidate and
flush every single pte entry, but only for s390.

Tested-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-30 00:29:10 +02:00
Sven Schnelle
f588c5cb0b s390/traps: Remove PIF_GUEST_FAULT
PIF_GUEST_FAULT is only used to pass information whether a fault was
caused when executing SIE or when executing host code. Instead of
using ptregs for this, just pass the flag directly as argument to
__do_pgm_check(). This also saves the time required to read the flag
from ptregs, although this likely isn't much as it is already in the
data cache.

Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-30 00:29:08 +02:00
Thomas Huth
6bef2c8b36 s390/uapi: Remove obsolete unistd_32.h from Kbuild file
unistd_32.h is not build anymore since commit 4ac286c4a8
("s390/syscalls: Switch to generic system call table generation").
Thus drop the superfluous line from the Kbuild file now, too.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-30 00:29:08 +02:00
K Prateek Nayak
cf0de88094 s390/runtime-const: Introduce runtime_const_mask_32()
Futex hash computation requires a mask operation with read-only after
init data that will be converted to a runtime constant in the subsequent
commit.

Introduce runtime_const_mask_32 to further optimize the mask operation
in the futex hash computation hot path.

GCC generates a:

  nilf %r1,<imm32>

to tackle arbitrary 32-bit masks and the same is implemented here.
Immediate patching pattern for __runtime_fixup_mask() has been adopted
from __runtime_fixup_ptr().

Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://patch.msgid.link/20260728052540.4728-7-kprateek.nayak@amd.com
2026-07-29 13:17:52 +02:00
Jaehoon Kim
9972befc3e KVM: s390: Fall back to short-term pinning in MAP ioctl
FOLL_LONGTERM pinning fails for some memory types, such as file-backed
guest memory. As a result, kvm_s390_adapter_map() returns -EINVAL and
irqfd adapter registration fails even though interrupt delivery could
still work via the existing non-atomic path.

When FOLL_LONGTERM pinning fails, verify that the page is accessible
using a short-term pin instead. If the short-term pin succeeds, unpin
the page and add a map entry with pinned=false to preserve MAP/UNMAP
symmetry. The non-atomic irqfd path already performs short-term pinning
for interrupt delivery, so this restores the previous behavior for
memory that cannot be pinned long-term.

get_map_info() is updated to return NULL for unpinned entries so that
the atomic irqfd fast path falls back to the non-atomic path.
kvm_s390_adapter_unmap() and kvm_s390_unmap_all_adapters() skip dirty
marking and unpin for unpinned entries.

Update Documentation/virt/kvm/devices/s390_flic.rst to reflect the
new MAP/UNMAP behavior.

Fixes: c9a5688380 ("KVM: s390: Add map/unmap ioctl and clean mappings post-guest")
Signed-off-by: Jaehoon Kim <jhkim@linux.ibm.com>
Reviewed-by: Douglas Freimuth <freimuth@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-07-27 09:23:53 +02:00
Thomas Gleixner
3ed403bbc9 treewide: Remove CLOCK_TICK_RATE
This has been scheduled for removal more than a decade ago and the comments
related to it have been dutifully ignored. The last dependencies are gone.

Remove it along with various now empty asm/timex.h files.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Link: https://patch.msgid.link/20260410120317.910770161@kernel.org
2026-07-15 15:04:55 +02:00
Jinjie Ruan
8383e05af7 syscall_user_dispatch: Introduce ARCH_SUPPORTS_SYSCALL_USER_DISPATCH
Currently, only x86 genuinely implements and supports Syscall User Dispatch
(SUD).

Multiple architectures provide a stub arch_syscall_is_vdso_sigreturn()
returning 'false' simply to satisfy GENERIC_ENTRY compilation, which
creates a false impression of feature support.

Introduce ARCH_SUPPORTS_SYSCALL_USER_DISPATCH to decouple this mechanism
from GENERIC_ENTRY. Select it exclusively on x86 and remove the redundant
stub functions from other architectures.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20260713035422.582771-1-ruanjinjie@huawei.com
2026-07-14 16:34:07 +02:00
Mete Durlu
397565b519 s390: Enable TIF_POLLING_NRFLAG
Enable TIF_POLLING_NRFLAG to support idle polling state in the
upcoming cpuidle driver.

Signed-off-by: Mete Durlu <meted@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-08 17:03:28 +02:00
Mete Durlu
71eabd104e s390/tick: Remove CIF_NOHZ_DELAY flag
Remove obsolete tick delay heuristic [1]. The upcoming cpuidle driver
handles frequent sleep/wakeup cycles more effectively.

[1] https://lore.kernel.org/all/20090929122533.402715150@de.ibm.com/

Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Mete Durlu <meted@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-08 17:03:28 +02:00
Gerald Schaefer
0e3d3b4bb0 s390/mm: Use set_pmd() / set_pud() for hugetlb pagetable entries
hugetlb code is known to view all pagetable entries as PTEs, instead of
corresponding upper levels like PMD or PUD. For s390, with different
pagetable entry layout for different levels, this requires some
conversion action under the hood.

The converted PMD and PUD entries are then written via set_pte()
function, but that might add some PTE-specific modifications.
There is no functional problem with current code, and the clearing of
_PAGE_UNUSED in set_pte(). Avoid future problems by using the set_pmd()
and set_pud() functions instead.

Signed-off-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2026-07-08 17:03:28 +02:00
Uwe Kleine-König (The Capable Hub)
ecca1d63c1 Replace <linux/mod_devicetable.h> by more specific <linux/device-id/*.h> (headers)
<linux/mod_devicetable.h> is included in a many files:

	$ git grep '<linux/mod_devicetable.h>' ef0c9f75a1 | wc -l
	1598

; some of them are widely used headers. To stop mixing up different and
unrelated driver( type)s let the subsystem headers only use the subset
of the recently split <linux/mod_devicetable.h> that are relevant for
them.

The fallout (I hope) is addressed in the previous commits that handle
sources relying on e.g. <linux/i2c.h> pulling in the full legacy header
and thus providing pci_device_id.

Acked-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://patch.msgid.link/199fe46b624ba07fb9bd3e0cd6ff13757932cb5f.1782808461.git.u.kleine-koenig@baylibre.com
Signed-off-by: Uwe Kleine-König (The Capable Hub) <u.kleine-koenig@baylibre.com>
2026-07-03 07:38:16 +02:00
Linus Torvalds
c75597caad s390:
* Fix S390_USER_OPEREXEC so it can now be enabled regardless of other
   unrelated capabilities
 
 * Fix handling of the _PAGE_UNUSED pte bit that could lead to guest
   memory corruption in some scenarios
 
 * A bunch of misc gmap fixes (locking, behaviour under memory pressure)
 
 * Fix CMMA dirty tracking
 
 x86:
 
 * Tidy up some WARN_ON() and BUG_ON(), replacing them with WARN_ON_ONCE()
   or KVM_BUG_ON().  All of these have obviously never triggered, or
   somebody would have been annoyed earlier, but still.
 
 * Fix missing interrupt due to stale CR8 intercept
 
 * Add a statistic that can come in handy to debug leaks as well as the
   vulnerability to a class of recently-discovered issues.
 
 * Do not ask arch/x86/kernel to export default_cpu_present_to_apicid()
   just for KVM.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCgAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmo7xaAUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroN7bwf/Ua6PrRrgdzfUGiIruBDnFGtXnaKf
 UPGpgl35Kl4ntPlmH6wRG6N0jP9sloa17Qj/Y33O1Um3Mi/eDV0UESW8o8tfFE2J
 CWUPc3/adw2urhnkXsoleSFy21a89TgLd0p4tot832p+IHi3iNJ45fx7XxftBeGt
 fa/liscncEX5tGwie0ZVkIEE/ob3+eX4ZYsTLXMi6FxAlyGPYNrp4jwJeYH9AFSd
 ZYGqVbDjDq14vhnppKXM8DMfHTXN4OVYw2RJZ9Y7u2h7ku3sN0XakzVTAUz5gtoM
 h+iu8dn5yslODBZiNGlls8UYm2bweOBCumH1ZITe/eTNuEdUOJGILorKRw==
 =QzfV
 -----END PGP SIGNATURE-----

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

Pull kvm fixes from Paolo Bonzini:
 "s390:

   - Fix S390_USER_OPEREXEC so it can now be enabled regardless of other
     unrelated capabilities

   - Fix handling of the _PAGE_UNUSED pte bit that could lead to guest
     memory corruption in some scenarios

   - A bunch of misc gmap fixes (locking, behaviour under memory
     pressure)

   - Fix CMMA dirty tracking

  x86:

   - Tidy up some WARN_ON() and BUG_ON(), replacing them with
     WARN_ON_ONCE() or KVM_BUG_ON(). All of these have obviously never
     triggered, or somebody would have been annoyed earlier, but still...

   - Fix missing interrupt due to stale CR8 intercept

   - Add a statistic that can come in handy to debug leaks as well as
     the vulnerability to a class of recently-discovered issues

   - Do not ask arch/x86/kernel to export
     default_cpu_present_to_apicid() just for KVM"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (22 commits)
  x86/apic: KVM: Use cpu_physical_id() to get APIC ID of running vCPU for AVIC
  KVM: x86/mmu: Expose number of shadow MMU shadow pages as a stat
  KVM: x86: Unconditionally recompute CR8 intercept on PPR update
  KVM: VMX: Grab vmcs12 on CR8 interception update iff vCPU is in guest mode
  KVM: x86: WARN (once) if RTC pending EOI tracking goes off the rails
  KVM: x86: WARN and fail kvm_set_irq() if a PIC or I/O APIC vector is invalid
  KVM: x86: Bug the VM, not the kernel, if the ISR count {under,over}flows
  KVM: x86/mmu: Bug the VM, not the host kernel, if KVM write-protects upper SPTEs
  KVM: x86: Replace BUG_ON() with WARN_ON_ONCE() on "bad" nested GPA translation
  KVM: Replace guest-triggerable BUG_ON() in ioeventfd datamatch with get_unaligned()
  KVM: s390: Return failure in case of failure in kvm_s390_set_cmma_bits()
  KVM: s390: selftests: Fix cmma selftest
  KVM: s390: Fix cmma dirty tracking
  KVM: s390: Fix locking in kvm_s390_set_mem_control()
  KVM: s390: Fix handle_{sske,pfmf} under memory pressure
  KVM: s390: Fix code typo in gmap_protect_asce_top_level()
  KVM: s390: Do not set special large pages dirty
  KVM: s390: Fix dat_peek_cmma() overflow
  s390/mm: Fix handling of _PAGE_UNUSED pte bit
  KVM: s390: Fix typo in UCONTROL documentation
  ...
2026-06-25 10:21:13 -07:00
Paolo Bonzini
91b16b53a0 KVM: s390: Fix S390_USER_OPEREXEC and more gmap fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEoWuZBM6M3lCBSfTnuARItAMU6BMFAmo7nlMACgkQuARItAMU
 6BPr+A//VLw9/5C2pgKVWRvJRVNcf8kIgAF1feONXJVoJiDGrbyiFcy4oCrppIZi
 OxAB2GvqV7Dbyu+tWH/iqPp3gxLf86sNh8JLkba8puWXP5SElyvVpEADYw8T97pX
 dL6j+9vYptMSTIVrhEYgiS5ghgCW6NymM2/6d+uWOCcPjuCaa2owO7K9fCsaLfAK
 O2D6HeRKEQdDszNKdplloSP5FjNn/t/zdPINclhfHdDNl7zSCF5Z3Y9cWGf+L2vL
 fYUiCPRPGANOreBcGMEBtDif667/U7nwiq7daC1rB+Q0MwRoq4h5jk0130aTTgXs
 hOA2EypipNO/ELO1hPJBNYTaSF1XjJMlrq5FHGkXXC+byWTsoKJgFXYkC9pQVd+r
 dcpu7S9nh9jkjSgc8F1+sNQ3+GHc9XrI214ALYgDr1PIZBevSlXaE3dtcU98+qtH
 IfKkonDEeRc8oZUTVLiINkQtZwtHqDKhqdhn5z508xJw5n+qr2oLEe/76NMjwH+E
 jteqA4WFaS2TGnOVf6IsYVdOQFMuOKrl+Se/M7fE1ZQ41IL4+aWT4gnpz3O+8sg9
 XmgiZJHXRtcH5nXfLbGryoO4HZPvwoV2mv0GmbmMVHBkve5qGqdElCRIQLAVImGc
 77/1DL73Kln7XawIik/MFDkCdt7GG3Qbqu1ALbKObCdJRSiFhzk=
 =OiBj
 -----END PGP SIGNATURE-----

Merge tag 'kvm-s390-next-7.2-2' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

* Fix S390_USER_OPEREXEC so it can now be enabled regardless of other
  unrelated capabilities

* Fix handling of the _PAGE_UNUSED pte bit that could lead to guest
  memory corruption in some scenarios

* A bunch of misc gmap fixes (locking, behaviour under memory pressure)

* Fix CMMA dirty tracking
2026-06-24 13:41:41 +02:00
Claudio Imbrenda
d4bb00704a s390/mm: Fix handling of _PAGE_UNUSED pte bit
The _PAGE_UNUSED softbit should not really be lying around. Its sole
purpose is to signal to try_to_unmap_one() and try_to_migrate_one()
that the page can be discarded instead of being moved / swapped.

KVM has no way to know why a page is being unmapped, so it sets the bit
on userspace ptes corresponding to unused guest pages every time they
get unmapped. KVM has no reasonable way to clear the bit once the page
is in use again.

While set_ptes() checks and clears the bit, other paths that set new
ptes did not. This led to used pages being thrown out as if they were
unused, causing guest corruption.

Fix the issue by clearing the _PAGE_UNUSED bit for present ptes in
set_pte(), i.e. whenever a present pte is getting set. The check in
set_ptes() is then redundant and can be removed.

Also fix gmap_helper_try_set_pte_unused() to only set the bit if the
pte is present; the _PAGE_UNUSED bit is only defined for present ptes
and thus should not be set for non-present ptes.

Fixes: c98175b791 ("KVM: s390: Add gmap_helper_set_unused()")
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260623153331.233784-2-imbrenda@linux.ibm.com>
2026-06-24 10:08:56 +02:00
Linus Torvalds
2580f89860 more s390 updates for 7.2 merge window
- consolidate s390 idle time accounting by moving all CPU time tracking
   to the architecture backend and eliminate the mix of architecture-
   specific and common code accounting
 
 - Add missing EXPORT_SYMBOL_GPL() to kcpustat_field_idle() and
   kcpustat_field_iowait() functions
 
 - Finalize ptep_get() conversion by replacing direct page table entry
   dereferencing with proper accessors (ptep_get(), pmdp_get(), etc.)
 
 - Explicitly check the buffer length in PKEY_VERIFYPROTK ioctl and
   pkey_pckmo implementations and fail if the length is exceeded
 -----BEGIN PGP SIGNATURE-----
 
 iI0EABYKADUWIQQrtrZiYVkVzKQcYivNdxKlNrRb8AUCajlD5xccYWdvcmRlZXZA
 bGludXguaWJtLmNvbQAKCRDNdxKlNrRb8K6cAP48oh4X6XLdK3Eohkm9WjkI0mxZ
 Qh/tkI1o1GcckwU/zAD+O0LKfJIcb4mo0cH7FgTOJTUCbmPBX711zjom2t9Bvww=
 =BTXg
 -----END PGP SIGNATURE-----

Merge tag 's390-7.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull more s390 updates from Alexander Gordeev:

 - consolidate s390 idle time accounting by moving all CPU time tracking
   to the architecture backend and eliminate the mix of architecture-
   specific and common code accounting

 - Add missing EXPORT_SYMBOL_GPL() to kcpustat_field_idle() and
   kcpustat_field_iowait() functions

 - Finalize ptep_get() conversion by replacing direct page table entry
   dereferencing with proper accessors (ptep_get(), pmdp_get(), etc.)

 - Explicitly check the buffer length in PKEY_VERIFYPROTK ioctl and
   pkey_pckmo implementations and fail if the length is exceeded

* tag 's390-7.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/pkey: Check length in pkey_pckmo handler implementation
  s390/pkey: Check length in PKEY_VERIFYPROTK ioctl
  s390/idle: Add missing EXPORT_SYMBOL_GPL()
  s390/mm: Complete ptep_get() conversion
  s390/idle: Remove idle time and count sysfs files
  s390/idle: Provide arch specific kcpustat_field_idle()/kcpustat_field_iowait()
  s390/irq/idle: Use stcke instead of stckf for time stamps
  s390/timex: Move union tod_clock type to separate header
2026-06-22 07:43:48 -07:00
Linus Torvalds
2e05544060 mm.git review status for mm-hotfixes-stable..mm-nonmm-stable
Everything:
 
 Total patches:       108
 Reviews/patch:       0.84
 Reviewed rate:       75%
 
 Patch series in this merge:
 
 - The 2 patch series "taskstats: fix TGID dead-thread stat retention"
   from Yiyang Chen fixes a taskstats TGID aggregation bug where fields
   added in the TGID query path were not preserved after thread exit, and
   adds a kselftest covering the regression.
 
 - The 2 patch series "lib/tests: string_helpers: Slight improvements"
   from Andy Shevchenko improves lib/tests/string_helpers_kunit.c a little.
 
 - The 2 patch series "lib/base64: decode fixes" from Josh Law addreesses
   minor issues in lib/base64.c.
 
 - The 3 patch series "selftests/filelock: Make output more kselftestish"
   from Mark Brown makes the output from the ofdlocks test a bit easier for
   tooling to work with, and also ignores the generated file.
 
 - The 3 patch series "uaccess: unify inline vs outline
   copy_{from,to}_user() selection" from Yury Norov simplifies the usercopy
   code by removing the selectability of inlining copy_{from,to}_user().
 
 - The 5 patch series "ocfs2: validate inline xattr header consumers"
   from ZhengYuan Huang fixes a number of possible issues in the ocfs2
   xattr code.
 
 - The 8 patch series "lib and lib/cmdline enhancements" from Dmitry
   Antipov provides additional robustness checking in the cmdline handling
   code and its in-kernel testing and selftests.
 
 - The 18 patch series "cleanup the RAID6 P/Q library" from Christoph
   Hellwig cleans up the RAID6 P/Q library to match the recent updates to
   the RAID 5 XOR library and other CRC/crypto libraries.
 
 - The 3 patch series "ocfs2: harden inode validators against forged
   metadata" from Michael Bommarito adds three structural checks to OCFS2
   dinode validation so malformed on-disk fields are rejected before
   ocfs2_populate_inode() copies them into the in-core inode.
 
 - The 2 patch series "lib/raid: replace __get_free_pages() call with
   kmalloc()" from Mike Rapoport cleans up the lib/raid code by using
   kmalloc() in more places.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCajgeIQAKCRDdBJ7gKXxA
 jmlWAQCLJVDZNJMFaXy4a+YHdu3tfemLpSy83A0Le61tOZUdBQD/Sf/7rhgeaM74
 32yp53TZLA8xHImCGEin/1ddPJ8DbgY=
 =GW2I
 -----END PGP SIGNATURE-----

Merge tag 'mm-nonmm-stable-2026-06-21-10-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - "taskstats: fix TGID dead-thread stat retention" (Yiyang Chen)

   Fix a taskstats TGID aggregation bug where fields added in the TGID
   query path were not preserved after thread exit, and adds a kselftest
   covering the regression.

 - "lib/tests: string_helpers: Slight improvements" (Andy Shevchenko)

   Improve lib/tests/string_helpers_kunit.c a little

 - "lib/base64: decode fixes" (Josh Law)

   Address minor issues in lib/base64.c

 - "selftests/filelock: Make output more kselftestish" (Mark Brown)

   Make the output from the ofdlocks test a bit easier for tooling to
   work with. Also ignore the generated file

 - "uaccess: unify inline vs outline copy_{from,to}_user() selection"
   (Yury Norov)

   Simplify the usercopy code by removing the selectability of inlining
   copy_{from,to}_user().

 - "ocfs2: validate inline xattr header consumers" (ZhengYuan Huang)

   Fix a number of possible issues in the ocfs2 xattr code

 - "lib and lib/cmdline enhancements" (Dmitry Antipov)

   Provide additional robustness checking in the cmdline handling code
   and its in-kernel testing and selftests

 - "cleanup the RAID6 P/Q library" (Christoph Hellwig)

   Clean up the RAID6 P/Q library to match the recent updates to the
   RAID 5 XOR library and other CRC/crypto libraries

 - "ocfs2: harden inode validators against forged metadata" (Michael
   Bommarito)

   Add three structural checks to OCFS2 dinode validation so malformed
   on-disk fields are rejected before ocfs2_populate_inode() copies them
   into the in-core inode

 - "lib/raid: replace __get_free_pages() call with kmalloc()" (Mike
   Rapoport)

   Clean up the lib/raid code by using kmalloc() in more places

* tag 'mm-nonmm-stable-2026-06-21-10-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (108 commits)
  ocfs2: fix circular locking dependency in ocfs2_dio_end_io_write
  ocfs2: fix NULL h_transaction deref in ocfs2_assure_trans_credits
  lib: interval_tree_test: validate benchmark parameters
  ocfs2: avoid moving extents to occupied clusters
  treewide: fix transposed "sign" typos and update spelling.txt
  ocfs2: fix UBSAN array-index-out-of-bounds in ocfs2_sum_rightmost_rec
  fat: reject BPB volumes whose data area starts beyond total sectors
  selftests/uevent: increase __UEVENT_BUFFER_SIZE to avoid ENOBUFS on busy systems
  lib/test_firmware: allocate the configured into_buf size
  fs: efs: remove unneeded debug prints
  checkpatch: cuppress warnings when Reported-by: is followed by Link:
  MAINTAINERS: add Alexander as a kcov reviewer
  mailmap: update Alexander Sverdlin's Email addresses
  fs: fat: inode: replace sprintf() with scnprintf()
  ocfs2: fix out-of-bounds write in ocfs2_remove_refcount_extent
  ocfs2: fix race between ocfs2_control_install_private() and ocfs2_control_release()
  ocfs2/dlm: require a ref for locking_state debugfs open
  ocfs2: reject FITRIM ranges shorter than a cluster
  ocfs2: validate fast symlink target during inode read
  ocfs2: add journal NULL check in ocfs2_checkpoint_inode()
  ...
2026-06-21 13:20:19 -07:00
Linus Torvalds
c98d767b34 Arm:
"This is a bit of an odd merge window on the KVM/arm64 front. There is
 absolutely no new feature in the pull request. It is purely fixes,
 because it is simply becoming too hard to review new stuff when so
 many AI-fuelled fixes hit the list".
 
 - Significant cleanup of the vgic-v5 PPI support which was merged in
   7.1. This makes the code more maintainable, and squashes a couple
   of bugs in the meantime.
 
 - Set of fixes for the handling of the MMU in an NV context,
   particularly VNCR-triggered faults. S1POE support is fixed
   as well.
 
 - Large set of pKVM fixes, mostly addressing recurring issues
   around hypervisor tracking of donated pages in obscure cases
   where the donation could fail and leave things in a bizarre
   state.
 
 - Fixes for the so-called "lazy vgic init", which resulted in
   sleeping operations in non-preemptible sections. This turned
   out to be far more invasive than initially expected...
 
 - Reduce the overhead of L1/L2 context switch by not touching
   the FP registers.
 
 - Fix the way non-implemented page sizes are dealt with when
   a guest insist on using them for S2 translation.
 
 - The usual set of low-impact fixes and cleanups all over the map.
 
 Loongarch:
 
 - On a request for lazy FPU load, load all FPU state that the VM
   supports instead of enabling only the part (FPU, LSX or LASX)
   that caused the FPU load request.
 
 - Some enhancements about interrupt injection.
 
 - Some bug fixes and other small changes.
 
 RISC-V:
 
 - Batch G-stage TLB flushes for GPA range based page table updates
 
 - Convert HGEI line management to fully per-HART
 
 - Fix missing CSR dirty marking when FWFT state updated via ONE_REG
 
 - Fix stale FWFT feature exposure to Guest/VM
 
 - Speed up dirty logging write faults using MMU rwlock and atomic
   PTE updates using cmpxchg() for permission-only changes
 
 - Use flexible array for APLIC IRQ state
 
 - Use kvm_slot_dirty_track_enabled() for logging enable check on
   a memslot
 
 - Avoid skipping valid pages in kvm_riscv_gstage_wp_range()
 
 - Avoid skipping valid pages in kvm_riscv_gstage_unmap_range()
 
 - Use endian-specific __lelong for NACL shared memory
 
 S390:
 
 - KVM_PRE_FAULT_MEMORY support
 
 - Support for 2G hugepages
 
 - Support for the ASTFLEIE 2 facility
 
 - Support for fast inject using kvm_arch_set_irq_inatomic
 
 - Fix potential leak of uninitialized bytes
 
 - A few more misc gmap fixes.
 
 x86:
 
 - Generic support for the more granular permissions allowed by EPT,
   namely "read" (which was previously usurping the U bit) and
   separate execution bits for kernel and userspace.
 
 - Do not assume that all page tables start with U=1/W=1/NX=0 at the
   root, as AMD GMET needs to have U=0 at the root.
 
 - Introduce common assembly macros for use within Intel and AMD
   vendor-specific vmentry code.  This touches the SPEC_CTRL handling,
   which is now entirely done in assembly for Intel (by reusing the
   AMD code that already existed), and register save/restore which
   uses some macro magic to compute the offsets in the struct.  Both
   of these are preparatory changes for upcoming APX support.
 
 - Clean up KVM's register tracking and storage, primarily to prepare for
   APX support, which expands the maximum number of GPRs from 16 to 32.
 
 - Keep a single copy of the PDPTRs rather than two, since architecturally
   there is just one.
 
 - Handle EXIT_FASTPATH_EXIT_USERSPACE in vendor code to ensure vendor code
   gets a chance to handle things like reaping the PML buffer.
 
 - Update KVM's view of PV async enabling if and only if the MSR write fully
   succeeds.
 
 - Fix a variety of issues where the emulator doesn't honor guest-debug state,
   and clean up related code along the way.
 
 - Synthesize EPT Violation and #NPF "error code" bits when injecting faults
   into L1 that didn't originate in hardware (in which case the VMCS/VMCB
   doesn't hold relevant information).
 
 - Add support for virtualizing (well, emulating) AMD's flavor of CPL>0 CPUID
   faulting.
 
 - Clean up the GPR APIs so that KVM's use of "raw" is consistent, and fix a
   variety of minor bugs along the way.
 
 - Fix an OOB memory access due to not checking the VP ID when handling a
   Hyper-V PV TLB flush for L2.
 
 - Fix a bug in the mediated PMU's handling of fixed counters that allowed the
   guest to bypass the PMU event filter.
 
 - Allow userspace to return EAGAIN when handling SNP and TDX hypercalls, so
   the KVM can forward a "retry" status code to the guest, and reserve all
   unused error codes for future usage.
 
 - Overhaul the TDP MMU => S-EPT code to move as much S-EPT specific logic as
   possible into the TDX code, and to funnel (almost) all S-EPT updates into
   a single chokepoint.  The motivation is largely to prepare for upcoming
   Dynamic PAMT support, but the cleanups are nice to have on their own.
 
 - Plug a hole in shadow page table handling, where KVM fails to recursively
   zap nested EPT/NPT shadow page tables when the nested hypervisor tears
   down its own EPT/NPT page tables from the bottom up
 
 x86 (Intel):
 
 - Support for nested MBEC (Mode-Based Execute Control), see above in the
   generic section; also run with MBEC enabled even for non-nested mode.
 
 - Use the kernel's "enum pg_level" in the TDX APIs instead of the TDX-Module's
   level definitions (which are 0-based).
 
 - Rework the TDX memory APIs to not require/assume that guest memory is
   backed by "struct page" (in prepartion for guest_memfd hugepage support).
 
 - Fix a largely benign bug where KVM TDX would incorrectly state it could
   emulate several x2APIC MSRs.
 
 - Use the "safe" WRMSR API when proxying LBR MSR writes as the to-be-written
   value is guest controlled and completely unvalidated.
 
 x86 (AMD):
 
 - Support for nested GMET (Guest Mode Execution Trap), see above in the
   generic section; also run with GMET enabled even for non-nested mode.
 
 - Fixes and minor cleanups to GHCB handling, on top of the earlier work
   already merged into 7.1-rc.
 
 - Ensure KVM's copy of CR0 and CR3 are up-to-date prior to invoking
   fastpath handlers.
 
 - Add support for virtualizing gPAT (KVM previously just used L1's PAT when
   running L2).
 
 - Fix goofs where KVM mishandles side effects (e.g. single-step and PMC
   updates) when emulating VMRUN.
 
 - Fix a variety of bugs in AVIC's handling of x2APIC MSR interception, most
   notably where KVM didn't disable interception of IRR, ISR, and TMR regs.
 
 - Add support for virtualizing Host-Only/Guest-Only bits in the mediated PMU.
 
 - Don't advertise support for unusable VM types, and account for VM types
   that are disabled by firmware, e.g. to mitigate security vulnerabilities.
 
 - Rewrite the SEV {en,de}crypt debug ioctls as they were riddle with bugs and
   unnecessarily complicated, and add comprehensive tests.
 
 - Clean up and deduplicate the SEV page pinning code.
 
 - Fix minor goofs related to writing back CPUID information after firmware
   rejects a CPUID page for an SNP vCPU.
 
 Generic:
 
 - Rename invalidate_begin() to invalidate_start() throughout KVM to follow
   the kernel's nomenclature, e.g. for mmu_notifiers.
 
 - Use guard() to cleanup up various KVM+VFIO flows.
 
 - Minor cleanups.
 
 guest_memfd:
 
 - Return -EEXIST instead of -EINVAL if userspace attempts to bind a gmem
   range to multiple memslots, and fix the test that was supposed to ensure
   KVM returns -EEXIST.
 
 - Treat memslot binding offsets and sizes as unsigned values to fix a bug
   where KVM interprets a large "offset + size" as a negative value and allows
   a nonsensical offset.
 
 - Use the inode number instead of the page offset for the NUMA interleaving
   index to fix a bug where the effective index would jump by two for
   consecutive pages (the caller also adds in the page offset).
 
 Selftests:
 
 - Randomize the dirty log test's delay when reaping the bitmap on the first
   pass, as always waiting only 1ms hid a KVM RISC-V bug as the test reaped the
   bitmap before KVM could build up enough state to hit the bug.
 
 - A pile of one-off fixes and cleanups.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCgAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmoypI0UHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroNCSAf8CyuvicojnZGFsNcoY4DZ0whBj5l8
 IwVkHaptuyGLSwPAebC/DwtU2NBY4CQdbtLjGmxenf+fSQOtcz1YWKbdY4Nr0hJG
 euAb/wO47RqKp1C4WPi7lL2P4XHgmUgD5XZ1qDnRV9gnGddZi3QLLmKgAtNq9Z4m
 +pAdGD2/RyZeI0Dx61+5ufE/z8YBlH6GrzgBTxfvvRNKqNDFykBenxYHI7seEfHC
 BPz0LxjHDD8BMDUo86qaylZnaeQSmFTGO/eTgvCvabxG6WbM1s0w3K1owmUmP7o3
 p9o8274Xh53iK2JYD/qGOtAJXejIwbYKT5bnvUQX0O1EH2+ouvSFapLQ9Q==
 =sSqM
 -----END PGP SIGNATURE-----

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

Pull kvm updates from Paolo Bonzini:
 "arm64:

     This is a bit of an odd merge window on the KVM/arm64 front. There
     is absolutely no new feature in the pull request. It is purely
     fixes, because it is simply becoming too hard to review new stuff
     when so many AI-fuelled fixes hit the list.

   - Significant cleanup of the vgic-v5 PPI support which was merged in
     7.1. This makes the code more maintainable, and squashes a couple
     of bugs in the meantime

   - Set of fixes for the handling of the MMU in an NV context,
     particularly VNCR-triggered faults. S1POE support is fixed as well

   - Large set of pKVM fixes, mostly addressing recurring issues around
     hypervisor tracking of donated pages in obscure cases where the
     donation could fail and leave things in a bizarre state

   - Fixes for the so-called "lazy vgic init", which resulted in
     sleeping operations in non-preemptible sections. This turned out to
     be far more invasive than initially expected..

   - Reduce the overhead of L1/L2 context switch by not touching the FP
     registers

   - Fix the way non-implemented page sizes are dealt with when a guest
     insist on using them for S2 translation

   - The usual set of low-impact fixes and cleanups all over the map

  Loongarch:

   - On a request for lazy FPU load, load all FPU state that the VM
     supports instead of enabling only the part (FPU, LSX or LASX) that
     caused the FPU load request

   - Some enhancements about interrupt injection

   - Some bug fixes and other small changes

  RISC-V:

   - Batch G-stage TLB flushes for GPA range based page table updates

   - Convert HGEI line management to fully per-HART

   - Fix missing CSR dirty marking when FWFT state updated via ONE_REG

   - Fix stale FWFT feature exposure to Guest/VM

   - Speed up dirty logging write faults using MMU rwlock and atomic PTE
     updates using cmpxchg() for permission-only changes

   - Use flexible array for APLIC IRQ state

   - Use kvm_slot_dirty_track_enabled() for logging enable check on a
     memslot

   - Avoid skipping valid pages in kvm_riscv_gstage_wp_range()

   - Avoid skipping valid pages in kvm_riscv_gstage_unmap_range()

   - Use endian-specific __lelong for NACL shared memory

  S390:

   - KVM_PRE_FAULT_MEMORY support

   - Support for 2G hugepages

   - Support for the ASTFLEIE 2 facility

   - Support for fast inject using kvm_arch_set_irq_inatomic

   - Fix potential leak of uninitialized bytes

   - A few more misc gmap fixes

  x86:

   - Generic support for the more granular permissions allowed by EPT,
     namely "read" (which was previously usurping the U bit) and
     separate execution bits for kernel and userspace

   - Do not assume that all page tables start with U=1/W=1/NX=0 at the
     root, as AMD GMET needs to have U=0 at the root

   - Introduce common assembly macros for use within Intel and AMD
     vendor-specific vmentry code. This touches the SPEC_CTRL handling,
     which is now entirely done in assembly for Intel (by reusing the
     AMD code that already existed), and register save/restore which
     uses some macro magic to compute the offsets in the struct. Both of
     these are preparatory changes for upcoming APX support

   - Clean up KVM's register tracking and storage, primarily to prepare
     for APX support, which expands the maximum number of GPRs from 16
     to 32

   - Keep a single copy of the PDPTRs rather than two, since
     architecturally there is just one

   - Handle EXIT_FASTPATH_EXIT_USERSPACE in vendor code to ensure vendor
     code gets a chance to handle things like reaping the PML buffer

   - Update KVM's view of PV async enabling if and only if the MSR write
     fully succeeds

   - Fix a variety of issues where the emulator doesn't honor
     guest-debug state, and clean up related code along the way

   - Synthesize EPT Violation and #NPF "error code" bits when injecting
     faults into L1 that didn't originate in hardware (in which case the
     VMCS/VMCB doesn't hold relevant information)

   - Add support for virtualizing (well, emulating) AMD's flavor of
     CPL>0 CPUID faulting

   - Clean up the GPR APIs so that KVM's use of "raw" is consistent, and
     fix a variety of minor bugs along the way

   - Fix an OOB memory access due to not checking the VP ID when
     handling a Hyper-V PV TLB flush for L2

   - Fix a bug in the mediated PMU's handling of fixed counters that
     allowed the guest to bypass the PMU event filter

   - Allow userspace to return EAGAIN when handling SNP and TDX
     hypercalls, so the KVM can forward a "retry" status code to the
     guest, and reserve all unused error codes for future usage

   - Overhaul the TDP MMU => S-EPT code to move as much S-EPT specific
     logic as possible into the TDX code, and to funnel (almost) all
     S-EPT updates into a single chokepoint. The motivation is largely
     to prepare for upcoming Dynamic PAMT support, but the cleanups are
     nice to have on their own

   - Plug a hole in shadow page table handling, where KVM fails to
     recursively zap nested EPT/NPT shadow page tables when the nested
     hypervisor tears down its own EPT/NPT page tables from the bottom
     up

  x86 (Intel):

   - Support for nested MBEC (Mode-Based Execute Control), see above in
     the generic section; also run with MBEC enabled even for non-nested
     mode

   - Use the kernel's "enum pg_level" in the TDX APIs instead of the
     TDX-Module's level definitions (which are 0-based)

   - Rework the TDX memory APIs to not require/assume that guest memory
     is backed by "struct page" (in prepartion for guest_memfd hugepage
     support)

   - Fix a largely benign bug where KVM TDX would incorrectly state it
     could emulate several x2APIC MSRs

   - Use the "safe" WRMSR API when proxying LBR MSR writes as the
     to-be-written value is guest controlled and completely unvalidated

  x86 (AMD):

   - Support for nested GMET (Guest Mode Execution Trap), see above in
     the generic section; also run with GMET enabled even for non-nested
     mode

   - Fixes and minor cleanups to GHCB handling, on top of the earlier
     work already merged into 7.1-rc

   - Ensure KVM's copy of CR0 and CR3 are up-to-date prior to invoking
     fastpath handlers

   - Add support for virtualizing gPAT (KVM previously just used L1's
     PAT when running L2)

   - Fix goofs where KVM mishandles side effects (e.g. single-step and
     PMC updates) when emulating VMRUN

   - Fix a variety of bugs in AVIC's handling of x2APIC MSR
     interception, most notably where KVM didn't disable interception of
     IRR, ISR, and TMR regs

   - Add support for virtualizing Host-Only/Guest-Only bits in the
     mediated PMU

   - Don't advertise support for unusable VM types, and account for VM
     types that are disabled by firmware, e.g. to mitigate security
     vulnerabilities

   - Rewrite the SEV {en,de}crypt debug ioctls as they were riddle with
     bugs and unnecessarily complicated, and add comprehensive tests

   - Clean up and deduplicate the SEV page pinning code

   - Fix minor goofs related to writing back CPUID information after
     firmware rejects a CPUID page for an SNP vCPU

  Generic:

   - Rename invalidate_begin() to invalidate_start() throughout KVM to
     follow the kernel's nomenclature, e.g. for mmu_notifiers

   - Use guard() to cleanup up various KVM+VFIO flows

   - Minor cleanups

  guest_memfd:

   - Return -EEXIST instead of -EINVAL if userspace attempts to bind a
     gmem range to multiple memslots, and fix the test that was supposed
     to ensure KVM returns -EEXIST

   - Treat memslot binding offsets and sizes as unsigned values to fix a
     bug where KVM interprets a large "offset + size" as a negative
     value and allows a nonsensical offset

   - Use the inode number instead of the page offset for the NUMA
     interleaving index to fix a bug where the effective index would
     jump by two for consecutive pages (the caller also adds in the page
     offset)

  Selftests:

   - Randomize the dirty log test's delay when reaping the bitmap on the
     first pass, as always waiting only 1ms hid a KVM RISC-V bug as the
     test reaped the bitmap before KVM could build up enough state to
     hit the bug

   - A pile of one-off fixes and cleanups"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (326 commits)
  KVM: x86/mmu: Ensure hugepage is in by slot before checking max mapping level
  KVM: x86: Fix shadow paging use-after-free due to unexpected role
  KVM: s390: Introducing kvm_arch_set_irq_inatomic fast inject
  KVM: s390: Enable adapter_indicators_set to use mapped pages
  KVM: s390: Add map/unmap ioctl and clean mappings post-guest
  riscv: kvm: Use endian-specific __lelong for NACL shared memory
  KVM: selftests: access_tracking_perf_test: bump number of NUMA nodes to 32
  KVM: s390: vsie: Implement ASTFLEIE facility 2
  KVM: s390: vsie: Refactor handle_stfle
  s390/sclp: Detect ASTFLEIE 2 facility
  KVM: s390: Minor refactor of base/ext facility lists
  KVM: x86/mmu: move pdptrs out of the MMU
  KVM: x86: check that kvm_handle_invpcid is only invoked with shadow paging
  KVM: nSVM: invalidate cached PDPTRs across nested NPT transitions
  KVM: nVMX: remove unnecessary code in prepare_vmcs02_rare
  KVM: x86: remove nested_mmu from mmu_is_nested()
  KVM: arm64: vgic-its: Make ABI commit helpers return void
  KVM: s390: Initialize KVM_S390_GET_CMMA_BITS memory
  LoongArch: KVM: Add missing slots_lock for device register/unregister
  LoongArch: KVM: Validate irqchip index in irqfd routing
  ...
2026-06-19 08:56:49 -07:00
Alexander Gordeev
28da1cce9e s390/mm: Complete ptep_get() conversion
Finalize commit c33c794828 ("mm: ptep_get() conversion") and
replace direct page table entry dereferencing with the proper
accessors (ptep_get(), pmdp_get(), etc.).

Override the default getter implementations even though they are
currently identical: pud_clear(), p4d_clear(), and pgd_clear()
require corresponding architecture-specific getters, but these
are not yet defined. This avoids a dependency loop.

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2026-06-16 17:30:31 +02:00