linux-stable.git/Documentation/virt, branch master Linux kernel stable tree Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2026-08-25T18:48:04+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-08-25T18:48:04+00:00 7bb6284aa7b3c369b41e7f33fcbe193161f008e7 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 ee1a586dd1fa "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 ... 
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 ee1a586dd1fa "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
  ...
Merge tag 'kvmarm-7.3' of https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD 2026-08-24T16:42:07+00:00 Paolo Bonzini pbonzini@redhat.com 2026-08-24T16:42:07+00:00 76671054f9a1ff6abb976583cd8da37650acdc97 KVM/arm64 changes for 7.3 - 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) 
KVM/arm64 changes for 7.3

 - 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)
Merge tag 'powerpc-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux 2026-08-18T19:08:13+00:00 Linus Torvalds torvalds@linux-foundation.org 2026-08-18T19:08:13+00:00 1200d84f4c0a929a0780180d25063d93773be79c Pull powerpc updates from Madhavan Srinivasan: - Enable Rust for ppc64le - ppc4xx gpio driver updates - Add power12 base enablement support - Validate arch_compat against host compatibility mode - Simplify bootx_scan_dt_build_struct() in powermac platform - Implement get_direction() in cpm2 - Use cpu_relax() in ps3_create_spu() - Add NULL guard for cause_ipi in smp_muxed_ipi_message_pass - Fixes to handle pseries watchdogs in kdump path - Fix missing r2 clobber in PCREL inline assembly - Set GPIO chip parent on ppc44x - KVM: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl - KVM: Use generic xfer to guest work function - Enable to run posix cpu timers in task context - Misc fixes and cleanups Thanks to Aditya Gupta, Alice Ryhl, Amit Machhiwal, Andrew Morton, Anushree Mathur, Athira Rajeev, Bartosz Golaszewski, Cédric Le Goater, Christian König, Christophe Leroy (CS GROUP), Gary Guo, Gaurav Batra, Gautam Menghani, Gou Hao, Hari Bathini, Harsh Prateek Bora, jiazhenyuan, Jinjie Ruan, Link Mauve, Linus Walleij, Mahesh Kumar G Mahesh Salgaonkar, Michael Walle, Michal Suchánek, Mukesh Kumar Chaurasiya (IBM), Nicholas Piggin, Nikhil Kumar Singh, Praveen K Pandey, Ritesh Harjani (IBM), Rosen Penev, Saket Kumar Bhaskar, Shrikanth Hegde, Sourabh Jain, Thorsten Blum, Vaibhav Jain, Venkat Rao Bagalkote, Vishal Chourasia, Wentao Guan, and Yanfei Xu. * tag 'powerpc-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (62 commits) powerpc/pseries/iommu: switch to Default DMA window during kdump powerpc/configs: enable CONFIG_RAS to fix EDAC support KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV KVM: PPC: Book3S HV: Implement compat CPU capability retrieval for KVM on PowerVM KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl gpio: ppc44x: use dev_name() for chip label gpio: ppc44x: fix undefined behavior in GPIO_MASK2 macro gpio: ppc44x: drop PPC-specific IO helpers gpio: ppc44x: Convert GPIO to generic MMIO gpio: ppc44x: Use platform resource helper for GPIO MMIO gpio: ppc44x: Use module platform driver helper for GPIO gpio: ppc44x: update all 4xx to 44x gpio: move ppc4xx gpio driver from arch/powerpc to drivers/gpio KVM: PPC: Use min() in kvm_vm_ioctl_check_extension() KVM: PPC: booke: Use min() in watchdog_next_timeout() powerpc/perf: Add power12 Base Performance Monitoring support powerpc: Add Power12 architected mode powerpc: Add Power12 raw mode powerpc/pseries: Limit PVR list to 16 entries for CAS negotiation ... 
Pull powerpc updates from Madhavan Srinivasan:

 - Enable Rust for ppc64le

 - ppc4xx gpio driver updates

 - Add power12 base enablement support

 - Validate arch_compat against host compatibility mode

 - Simplify bootx_scan_dt_build_struct() in powermac platform

 - Implement get_direction() in cpm2

 - Use cpu_relax() in ps3_create_spu()

 - Add NULL guard for cause_ipi in smp_muxed_ipi_message_pass

 - Fixes to handle pseries watchdogs in kdump path

 - Fix missing r2 clobber in PCREL inline assembly

 - Set GPIO chip parent on ppc44x

 - KVM: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl

 - KVM: Use generic xfer to guest work function

 - Enable to run posix cpu timers in task context

 - Misc fixes and cleanups

Thanks to Aditya Gupta, Alice Ryhl, Amit Machhiwal, Andrew Morton,
Anushree Mathur, Athira Rajeev, Bartosz Golaszewski, Cédric Le Goater,
Christian König, Christophe Leroy (CS GROUP), Gary Guo, Gaurav Batra,
Gautam Menghani, Gou Hao, Hari Bathini, Harsh Prateek Bora, jiazhenyuan,
Jinjie Ruan, Link Mauve, Linus Walleij, Mahesh Kumar G Mahesh
Salgaonkar, Michael Walle, Michal Suchánek, Mukesh Kumar Chaurasiya
(IBM), Nicholas Piggin, Nikhil Kumar Singh, Praveen K Pandey, Ritesh
Harjani (IBM), Rosen Penev, Saket Kumar Bhaskar, Shrikanth Hegde,
Sourabh Jain, Thorsten Blum, Vaibhav Jain, Venkat Rao Bagalkote, Vishal
Chourasia, Wentao Guan, and Yanfei Xu.

* tag 'powerpc-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (62 commits)
  powerpc/pseries/iommu: switch to Default DMA window during kdump
  powerpc/configs: enable CONFIG_RAS to fix EDAC support
  KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl
  KVM: PPC: Book3S HV: Add support for compat CPU capabilities for KVM on PowerNV
  KVM: PPC: Book3S HV: Implement compat CPU capability retrieval for KVM on PowerVM
  KVM: PPC: Introduce KVM_CAP_PPC_COMPAT_CAPS and wire up ioctl
  gpio: ppc44x: use dev_name() for chip label
  gpio: ppc44x: fix undefined behavior in GPIO_MASK2 macro
  gpio: ppc44x: drop PPC-specific IO helpers
  gpio: ppc44x: Convert GPIO to generic MMIO
  gpio: ppc44x: Use platform resource helper for GPIO MMIO
  gpio: ppc44x: Use module platform driver helper for GPIO
  gpio: ppc44x: update all 4xx to 44x
  gpio: move ppc4xx gpio driver from arch/powerpc to drivers/gpio
  KVM: PPC: Use min() in kvm_vm_ioctl_check_extension()
  KVM: PPC: booke: Use min() in watchdog_next_timeout()
  powerpc/perf: Add power12 Base Performance Monitoring support
  powerpc: Add Power12 architected mode
  powerpc: Add Power12 raw mode
  powerpc/pseries: Limit PVR list to 16 entries for CAS negotiation
  ...
Merge tag 'kvm-x86-generic-7.3' of https://github.com/kvm-x86/linux into HEAD 2026-08-18T11:13:25+00:00 Paolo Bonzini pbonzini@redhat.com 2026-08-18T11:13:25+00:00 9dc54ddece8af88b9d1ee8036c11b16a0be53bfa KVM arch-neutral and documentation changes for 7.3 - Remove kvm_debugfs_dir if kvm_init() fails after creating KVM's debugfs. - Document some of the "fun" gotchas with the APIC base when creating IRQCHIPs on x86. - 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). - 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. 
KVM arch-neutral and documentation changes for 7.3

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

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

 - 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).

 - 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.
KVM: PPC: Document KVM_PPC_GET_COMPAT_CAPS ioctl 2026-08-09T14:56:43+00:00 Amit Machhiwal amachhiw@linux.ibm.com 2026-08-08T16:11:48+00:00 c1721e584244ff79a593d6f0ad0405a2e07b765a Add documentation for the KVM_PPC_GET_COMPAT_CAPS ioctl to the KVM API documentation. The ioctl exposes host processor compatibility modes supported for nested KVM guests on PowerPC systems. The documentation covers error code descriptions including E2BIG for forward compatibility, KVM_PPC_COMPAT_CAPS_SIZE_VER0 as the minimum size floor, the rationale for rejecting non-zero reserved fields to prevent ABI ambiguity, bit numbering clarification for IBM MSB-0 convention, and KVM-specific capability bit constants. Tested-by: Gautam Menghani <gautam@linux.ibm.com> Reviewed-by: Gautam Menghani <gautam@linux.ibm.com> Tested-by: Anushree Mathur <anushree.mathur@linux.ibm.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com> Signed-off-by: Amit Machhiwal <amachhiw@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20260808161148.66673-5-amachhiw@linux.ibm.com 
Add documentation for the KVM_PPC_GET_COMPAT_CAPS ioctl to the KVM API
documentation.

The ioctl exposes host processor compatibility modes supported for
nested KVM guests on PowerPC systems. The documentation covers error
code descriptions including E2BIG for forward compatibility,
KVM_PPC_COMPAT_CAPS_SIZE_VER0 as the minimum size floor, the rationale
for rejecting non-zero reserved fields to prevent ABI ambiguity, bit
numbering clarification for IBM MSB-0 convention, and KVM-specific
capability bit constants.

Tested-by: Gautam Menghani <gautam@linux.ibm.com>
Reviewed-by: Gautam Menghani <gautam@linux.ibm.com>
Tested-by: Anushree Mathur <anushree.mathur@linux.ibm.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Amit Machhiwal <amachhiw@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260808161148.66673-5-amachhiw@linux.ibm.com
KVM: x86: Document APIC base address constraint for in-kernel irqchip 2026-07-31T22:13:03+00:00 Tim Wiederhake twiederh@redhat.com 2026-07-08T13:38:55+00:00 99607da19b66ca6649088176ecaaa83eeae780b7 When virtual APIC access acceleration is enabled (APICv on Intel, AVIC on AMD), vcpu creation installs a private memory slot at the default APIC base address (0xfee00000). If a user memory region overlaps this address, vcpu creation fails with EEXIST. The same error occurs when installing an overlapping user memory region after vcpu creation. This also applies when using KVM_CAP_SPLIT_IRQCHIP. This constraint is not documented anywhere. Add a note to the KVM_CREATE_IRQCHIP and KVM_CAP_SPLIT_IRQCHIP documentation. Signed-off-by: Tim Wiederhake <twiederh@redhat.com> Link: https://patch.msgid.link/20260708133856.302151-3-twiederh@redhat.com [sean: call out "subsequent vcpu creation"] Signed-off-by: Sean Christopherson <seanjc@google.com> 
When virtual APIC access acceleration is enabled (APICv on Intel, AVIC
on AMD), vcpu creation installs a private memory slot at the default
APIC base address (0xfee00000).  If a user memory region overlaps this
address, vcpu creation fails with EEXIST.  The same error occurs when
installing an overlapping user memory region after vcpu creation.

This also applies when using KVM_CAP_SPLIT_IRQCHIP.

This constraint is not documented anywhere.  Add a note to the
KVM_CREATE_IRQCHIP and KVM_CAP_SPLIT_IRQCHIP documentation.

Signed-off-by: Tim Wiederhake <twiederh@redhat.com>
Link: https://patch.msgid.link/20260708133856.302151-3-twiederh@redhat.com
[sean: call out "subsequent vcpu creation"]
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM: x86: Document that KVM_CREATE_IRQCHIP must precede vCPU creation 2026-07-31T22:10:36+00:00 Tim Wiederhake twiederh@redhat.com 2026-07-08T13:38:54+00:00 d82d77c6430ccd4482b57fc1d22b80649ef71ad8 The kernel rejects KVM_CREATE_IRQCHIP with -EINVAL if any vCPUs have already been created, but the API documentation does not mention this constraint. Add a note. Signed-off-by: Tim Wiederhake <twiederh@redhat.com> Link: https://patch.msgid.link/20260708133856.302151-2-twiederh@redhat.com Signed-off-by: Sean Christopherson <seanjc@google.com> 
The kernel rejects KVM_CREATE_IRQCHIP with -EINVAL if any vCPUs have
already been created, but the API documentation does not mention this
constraint.  Add a note.

Signed-off-by: Tim Wiederhake <twiederh@redhat.com>
Link: https://patch.msgid.link/20260708133856.302151-2-twiederh@redhat.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
KVM: arm64: Add KVM_ARM_VCPU_PMU_V3_STRICT vCPU feature 2026-07-31T06:35:24+00:00 Congkai Tan congkai@amazon.com 2026-07-22T20:27:02+00:00 ad220e275c3987aea865d4c05ad66ba0295c494d Introduce a new vCPU feature KVM_ARM_VCPU_PMU_V3_STRICT. When set, KVM does not create a default PMU when initializing the vCPU, and userspace must select one explicitly via KVM_ARM_VCPU_PMU_V3_SET_PMU before the first KVM_RUN. The flag forces the VMM to be aware of the PMU implementation of the guest to be created, so that certain information about the PMU becomes deterministic (if on a heterogeneous system) and becomes safe to be exposed to the guest. It can be used as an umbrella flag to gate future PMUv3 UAPI changes. When no default PMU is created, kvm->arch.arm_pmu stays NULL until SET_PMU runs, so kvm_arm_pmu_v3_init() now refuses to run if kvm->arch.arm_pmu is NULL. Signed-off-by: Congkai Tan <congkai@amazon.com> Reviewed-by: Geoff Blake <blakgeof@amazon.com> Reviewed-by: Haris Okanovic <harisokn@amazon.com> Reviewed-by: Stanislav Spassov <stanspas@amazon.de> Co-developed-by: Oliver Upton <oupton@kernel.org> Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev> Tested-by: Fuad Tabba <fuad.tabba@linux.dev> Link: https://patch.msgid.link/20260722202702.4165917-5-congkai@amazon.com Signed-off-by: Oliver Upton <oupton@kernel.org> 
Introduce a new vCPU feature KVM_ARM_VCPU_PMU_V3_STRICT. When set, KVM
does not create a default PMU when initializing the vCPU, and userspace
must select one explicitly via KVM_ARM_VCPU_PMU_V3_SET_PMU before the
first KVM_RUN.

The flag forces the VMM to be aware of the PMU implementation of the
guest to be created, so that certain information about the PMU becomes
deterministic (if on a heterogeneous system) and becomes safe to be
exposed to the guest. It can be used as an umbrella flag to gate future
PMUv3 UAPI changes.

When no default PMU is created, kvm->arch.arm_pmu stays NULL until SET_PMU
runs, so kvm_arm_pmu_v3_init() now refuses to run if kvm->arch.arm_pmu
is NULL.

Signed-off-by: Congkai Tan <congkai@amazon.com>
Reviewed-by: Geoff Blake <blakgeof@amazon.com>
Reviewed-by: Haris Okanovic <harisokn@amazon.com>
Reviewed-by: Stanislav Spassov <stanspas@amazon.de>
Co-developed-by: Oliver Upton <oupton@kernel.org>
Reviewed-by: Fuad Tabba <fuad.tabba@linux.dev>
Tested-by: Fuad Tabba <fuad.tabba@linux.dev>
Link: https://patch.msgid.link/20260722202702.4165917-5-congkai@amazon.com
Signed-off-by: Oliver Upton <oupton@kernel.org>
Merge tag 'kvmarm-fixes-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD 2026-07-28T15:43:23+00:00 Paolo Bonzini pbonzini@redhat.com 2026-07-28T15:43:23+00:00 a7fe52b5ab9e1fdb53a8a111a0f427bbff4cb91e KVM/arm64 fixes for 7.2, take #3 - Fix a tiny buglet when propagating the deactivation of an interrupt from a nested guest, which happened to trigger a gold plated CPU bug on a particular implementation - Fix a race between LPI unmapping and mapping, resulting in leaked LPIs - Make LPI mapping more robust on memory allocation failure - Fix the handling of the EL2 tracing clock being disabled - A couple of Sashiko-driven fixes for corner cases in the EL2 tracing code - Add missing sysreg tracepoint for the EL2 code - Tidy-up the mutual exclusion of guest-memfd and MTE - Update Fuad's email address to point to @linux.dev 
KVM/arm64 fixes for 7.2, take #3

- Fix a tiny buglet when propagating the deactivation of an interrupt
  from a nested guest, which happened to trigger a gold plated CPU bug
  on a particular implementation

- Fix a race between LPI unmapping and mapping, resulting in leaked
  LPIs

- Make LPI mapping more robust on memory allocation failure

- Fix the handling of the EL2 tracing clock being disabled

- A couple of Sashiko-driven fixes for corner cases in the EL2 tracing
  code

- Add missing sysreg tracepoint for the EL2 code

- Tidy-up the mutual exclusion of guest-memfd and MTE

- Update Fuad's email address to point to @linux.dev
KVM: s390: Fall back to short-term pinning in MAP ioctl 2026-07-27T07:23:53+00:00 Jaehoon Kim jhkim@linux.ibm.com 2026-07-24T13:39:43+00:00 9972befc3e34ff8b6847198c84f11bfc312dde40 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: c9a568838086 ("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> 
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: c9a568838086 ("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>