kernel/linux.git/Documentation/virt, branch v7.2-rc1

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

2026-06-25T17:21:13+00:00

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 ...

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

2026-06-24T11:41:41+00:00

* 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

KVM: s390: Fix typo in UCONTROL documentation

2026-06-24T08:01:57+00:00

Small typo noticed while writing the USER_OPEREXEC selftest. Signed-off-by: Eric Farman Reviewed-by: Hendrik Brueckner Reviewed-by: Claudio Imbrenda Message-ID: <20260507200836.3500368-4-farman@linux.ibm.com> Signed-off-by: Claudio Imbrenda

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

2026-06-19T15:56:49+00:00

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 ...

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

2026-06-16T03:05:59+00:00

Pull documentation updates from Jonathan Corbet: "Things have calmed down a bit on the docs front, with no earthshaking changes this time around: - Ongoing work on the Japanese and Portuguese translations - Better integration of the MAINTAINERS file into the rendered documents, including a search interface - A seemingly infinite supply of fixes for typos, minor grammatical issues, and related problems that LLMs find with abandon" * tag 'docs-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (93 commits) docs: pt_BR: Translate 3.Early-stage.rst into Portuguese docs: pt_BR: update "Purpose of Defconfigs" section in maintainer-soc.rst Documentation: bug-hunting.rst: fix grammar docs/ja_JP: translate submitting-patches.rst (interleaved-replies) docs: Fix minor grammatical error docs/{it_it,sp_SP,zh_CN,zh_TW}: update references to removed CONFIG_DEBUG_SLAB Documentation: process: fix brackets Documentation: arch: fix brackets docs/dyndbg: explain flags parse 1st docs/dyndbg: update examples \012 to \n docs: kernel-parameters: Fix stale sticore file paths docs: real-time: Fix duplicated sched(7) text docs: kgdb: Fix stale source file paths docs: sonypi: Fix stale header file path docs: kernel-parameters: Remove sa1100ir IrDA parameter iommu: Documentation: rearrange, update kernel-parameters docs: md: fix grammar in speed_limit description docs: changes.rst: restore pahole 1.26 minimum (regressed by sort) Documentation: Fix syntax of kmalloc_objs example in coding style doc docs: pt_BR: update maintainer-handbooks ...

Merge tag 'kvm-s390-next-7.2-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

2026-06-15T13:36:43+00:00

KVM: s390: New features for 7.2 New features for 7.2 for KVM/s390: * KVM_PRE_FAULT_MEMORY support * Support for 2G hugepages * Support for the ASTFLEIE 2 facility * kvm_arch_set_irq_inatomic Fast Inject * Fix potential leak of uninitialized bytes

Merge tag 'kvmarm-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2026-06-12T08:51:42+00:00

KVM/arm64 updates for 7.2 * New features: - None. Zilch. Nada. Que dalle. * Fixes and other improvements: - 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.

Merge tag 'kvm-x86-svm-7.2' of https://github.com/kvm-x86/linux into HEAD

2026-06-12T08:16:59+00:00

KVM SVM changes for 7.2 - 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.

Merge tag 'kvm-x86-misc-7.2' of https://github.com/kvm-x86/linux into HEAD

2026-06-12T08:11:09+00:00

KVM misc x86 changes for 7.2 - Handle EXIT_FASTPATH_EXIT_USERSPACE in vendor code to ensure vendor code gets a chance to handle things like reaping the PML buffer. - Ensure KVM's copy of CR0 and CR3 are up-to-date on SVM prior to invoking fastpath handlers. - 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. - Misc fixes and cleanups.

Merge branch kvm-arm64/vgic-v5-PPI-fixes into kvmarm-master/next

2026-06-12T08:08:31+00:00

* kvm-arm64/vgic-v5-PPI-fixes: : . : Substantial cleanup of the vgic-v5 PPI support. From the original : cover letter: : : "With the GICv5 PPi support merged in, it has become obvious that a few : things could be improved, both from the correctness and maintainability : angles." : . KVM: arm64: Fix arch timer interrupts for GICv3-on-GICv5 guests irqchip/gic-v5: Immediately exec priority drop following activate Documentation: KVM: Clarify that PMU_V3_IRQ IntID requirements for GICv5 Documentation: KVM: Fix typos in VGICv5 documentation KVM: arm64: selftests: Improve error handling for GICv5 PPI selftest KVM: arm64: selftests: Cleanup unused vars in GICv5 PPI selftest KVM: arm64: selftests: Add missing GIC CDEN to no-vgic-v5 selftest KVM: arm64: vgic-v5: Atomically assign bits to PPI DVI bitmap KVM: arm64: vgic-v5: Add missing trap handing for NV triage KVM: arm64: vgic-v5: Limit support to 64 PPIs KVM: arm64: vgic: Rationalise per-CPU irq accessor KVM: arm64: vgic-v5: Drop defensive checks from vgic_v5_ppi_queue_irq_unlock() KVM: arm64: vgic: Consolidate vgic_allocate_private_irqs_locked() KVM: arm64: vgic: Constify struct irq_ops usage KVM: arm64: vgic-v5: Drop pointless ARM64_HAS_GICV5_CPUIF check KVM: arm64: vgic-v5: Remove use of __assign_bit() with a constant KVM: arm64: vgic-v5: Move PPI caps into kvm_vgic_global_state KVM: arm64: vgic-v5: Add for_each_visible_v5_ppi() iterator Signed-off-by: Marc Zyngier