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2026-09-21Merge tag 'kvmarm-fixes-7.3-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEADPaolo Bonzini1-2/+2
KVM/arm64 changes for 7.3, take #2 - Invalidate the ITS translation cache when the guest changes the base address of the ITS tables (Fuad Tabba) - Skip saving ITS devices with device IDs that are out-of-bounds rather than failing the entire ITS save ioctl (Fuad Tabba) - Close race between VM teardown and invalidations of nested MMUs when handling MMU operations that are allowed to block (Lorenzo Stoakes) - Various fixes for the handling of the host's untrusted SVE configuration in pKVM (Fuad Tabba) - Make sure that empty SMCCC ranges based at 0 are rejected by the kvm_smccc_set_filter() (Karl Mehltretter) - Revoke the host mapping for pKVM's private stack pages, along with a new sanity check that all mappings in the hyp's private VA range have been correctly marked as hyp-owned (Fuad Tabba) - Lifetime fixes for the array of shadow stage-2 MMUs, ensuring that concurrent vCPU initialization cannot relocate in-use MMUs. Defer the freeing of shadow stage-2 MMUs to the point that no other users (e.g. MMU notifier) could reference them (Marc Zyngier) - Drop useless WARN when rejecting an unsupported ioctl for pKVM (Fuad Tabba) - Fix the steal_time selftest to install correctly-sized mappings for non-4K hosts (Sebastian Ott) - Correct mapping of fine-grained trap for GCSPOPX instruction (Mark Brown) - Fix KVM_BUG_ON() due to missing handling of DBGBXVR<n> from 32-bit guests (Karl Mehltretter)
2026-09-04treewide: refresh kmalloc_obj() conversionsKees Cook1-2/+2
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-09-01KVM: s390: Fix race in _destroy_pages_crste()Claudio Imbrenda1-2/+4
Use READ_ONCE() in _destroy_pages_crste() to read the crste, avoid dereferencing the pointer multiple times. Fixes: a2c17f9270cc ("KVM: s390: New gmap code") Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260828115439.145885-9-imbrenda@linux.ibm.com>
2026-09-01KVM: s390: Fix potential races in dat skey functionsClaudio Imbrenda1-8/+28
When dat_cond_set_storage_key() finds a large page, it will conditionally set the storage key in absolute memory using large_crste_to_phys() to get the absolute address. There is a race window between dat_entry_walk() and large_crste_to_phys(): the large page could have been split concurrently, and large_crste_to_phys() might be called with a crste that does not designate a large page, leading to crashes. Similar issues were also present in dat_set_storage_key(). dat_get_storage_key() and dat_reset_reference_bit() did instead check for a potential concurrent splitting of the large page, but then handled it incorrectly. Fix by performing a READ_ONCE on the crste pointer, checking and using the result, instead of dereferencing the pointer again. In case a race is detacted, try dat_entry_walk() again. Fixes: 8e03e8316eb2 ("KVM: s390: KVM page table management functions: storage keys") Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260828115439.145885-8-imbrenda@linux.ibm.com>
2026-09-01KVM: s390: Add missing srcu in kvm_s390_set_irq_state()Claudio Imbrenda1-2/+2
Like kvm_s390_inject_vcpu(), kvm_s390_set_irq_state() also needs the kvm->srcu or the slots lock when performing the Store status operation. Fix by taking kvm->srcu in kvm_s390_set_irq_state(). Fixes: ba5c1e9b6cee ("KVM: s390: interrupt subsystem, cpu timer, waitpsw") Fixes: 062e44a9319f ("KVM: s390: Use srcu in kvm_arch_vcpu_unlocked_ioctl()") Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260828115439.145885-7-imbrenda@linux.ibm.com>
2026-09-01KVM: s390: Move all code into s390_kvm_mmu_prepare_memory_region()Claudio Imbrenda3-58/+36
Move all code from s390_kvm_mmu_commit_memory_region() into s390_kvm_mmu_prepare_memory_region(). This allows the function to fail gracefully if needed. The previous behaviour was to print a warning and continue execution with page tables inconsistent with the memslots. Fixes: e38c884df921 ("KVM: s390: Switch to new gmap") Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260828115439.145885-6-imbrenda@linux.ibm.com>
2026-09-01KVM: s390: Refactor dat_set_slot()Claudio Imbrenda3-28/+15
Refactor dat_set_slot(), _dat_slot_pte(), _dat_slot_crste(). Now they only take a struct kvm_s390_mmu_cache as priv. For dat_delete_slot(), mc is NULL, as no allocations should take place. This is needed as a prerequisite to move gmap DAT table setup from kvm_arch_commit_memory_region() to kvm_arch_prepare_memory_region(). Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260828115439.145885-5-imbrenda@linux.ibm.com>
2026-09-01KVM: s390: Fix _gaccess_shadow_fault()Claudio Imbrenda1-0/+13
In some circumstances, it is possible that the page of nested guest memory that is being shadowed is not present at all in the parent guest gmap. dat_entry_walk() will not find any leaf entry and return with -ENOENT, which will erroneously be propagated all the way to userspace. Fix by manually calling gmap_link() on the memory of the nested guest that is being shadowed if the mapping was not already present. Fixes: e38c884df921 ("KVM: s390: Switch to new gmap") Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260828115439.145885-4-imbrenda@linux.ibm.com>
2026-09-01KVM: s390: Fix compile warning for kvm_s390_update_cmma_dirty()Claudio Imbrenda2-2/+2
The parameter "old" should be marked as const, to prevent compile-time warnings. Fixes: d487a24041c2 ("KVM: s390: Prepare gmap for a second KVM implementation") Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260828115439.145885-3-imbrenda@linux.ibm.com>
2026-09-01KVM: s390: Fix dirty marking in adapter_indicators_set*()Claudio Imbrenda1-37/+38
When the indicator and/or summary bits are set in the guest, the accessed page was only marked dirty in KVM if the access was performed using the slow path; accesses through the new kvm_arch_set_irq_inatomic fast inject path would not mark the page as dirty. Fix by adding/moving the missing calls to mark_page_dirty(). Note that for the inatomic path set_page_dirty{,_lock}() is not needed as the page stays pinned; the unpin path correctly marks it as dirty. Opportunistically reorder the local variables to be in reverse Christmas tree order and refactor to use guard(). Fixes: 1e95e3bc6b05 ("KVM: s390: Enable adapter_indicators_set to use mapped pages") Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260828115439.145885-2-imbrenda@linux.ibm.com>
2026-08-25Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds28-255/+452
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 ...
2026-08-23Merge tag 's390-7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds5-21/+10
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 ...
2026-08-13KVM: s390: gmap: Make prefix handling optionalSteffen Eiden4-7/+25
Guard guest prefix handling behind `KVM_S390_MANAGES_S390_GUEST`. This enables other KVM implementations to use gmap without implementing prefix handling. The prefix handling is integrated deeply in the gmap implementation. Therefore, provide safe default implementations for the guarded functions. No functional changes. 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>
2026-08-13KVM: s390: gmap: Make CMMA optionalSteffen Eiden4-1/+9
Guard guest CMMA behind `KVM_S390_MANAGES_S390_GUEST`. This enables other KVM implementations to use gmap without implementing CMMA. No functional changes. 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>
2026-08-13KVM: s390: gmap: Make storage keys optionalSteffen Eiden4-0/+15
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>
2026-08-13KVM: s390: Prepare gmap for a second KVM implementationSteffen Eiden5-112/+175
Refactor gmap code such that a second s390 (host) KVM implementation can use the gmap code as well. Move mmu code from s390 to gmap so the other KVM implementation can use it as well. 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>
2026-08-13KVM: s390: Move s390 kvm code into a subdirectorySteffen Eiden26-11/+21
Move all the code required to run s390 KVM guests on s390 to a s390 subdirectory. Move gmap related code into a gmap directory to later share gmap code between KVM implementations. Update S390 VFIO-PCI MAINTAINERS filepath. 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>
2026-08-13KVM: s390: Rename kvm-s390.{c,h} to s390.{c,h}Steffen Eiden15-16/+16
Rename kvm-s390.c to s390.c and kvm-s390.h to s390.h for consistency with the new directory structure. Update all include statements and simplify Makefile ccflags from explicit paths to -I$(src). 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>
2026-08-13KVM: s390: Prepare include guards for a new locationSteffen Eiden3-9/+9
Update include guard names in dat.h, faultin.h, and gmap.h to ARCH_KVM_GMAP_* to reflect their upcoming relocation to a shared gmap directory. 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>
2026-08-13KVM: s390: Extract gmap tracing to a separate headerSteffen Eiden3-15/+49
Move the kvm_s390_major_guest_pfault trace event from trace.h to a new trace_gmap.h header. This separates gmap-specific tracing from general KVM/s390 tracing, preparing for code sharing between multiple KVM implementations. The trace event definition is updated to use local defines for parameters so that they can be replaced later with ease for when another KVM implementation uses these traces. 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>
2026-08-12Merge remote-tracking branch 'kvms390/master' into 'kvms390/next'Christian Borntraeger12-195/+385
2026-08-12KVM: s390: Fix potential tiny kernel stack leakClaudio Imbrenda1-0/+1
In some circumstances, one bit of kernel stack could have been leaked from dat_cond_set_storage_key(). Fix by clearing prev before use. Fixes: 8e03e8316eb2 ("KVM: s390: KVM page table management functions: storage keys") Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260812104436.109741-9-imbrenda@linux.ibm.com>
2026-08-12KVM: s390: Fix kvm_s390_clear_pv_state()Claudio Imbrenda1-0/+4
kvm_s390_clear_pv_state() needs to also clear the dumping flag, to allow the protected VM to be started again (as non-protected, with all protected state safely destroyed) after a forced reboot while a protected dump was ongoing and not completed. Fixes: e40df9efd68a ("KVM: s390: pv: clear the state without memset") Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260812104436.109741-8-imbrenda@linux.ibm.com>
2026-08-12KVM: s390: Fix IRQ injection with SIGP Stop and Store StatusClaudio Imbrenda1-32/+38
When __inject_sigp_stop() is called for a Stop and Store Status operation, if the vCPU is running, the interrupt is marked as pending and the status is stored by the thread performing the KVM_RUN IOCTL. If the vCPU is already stopped, the status is stored immediately. Storing the status means writing into userspace, which might fault, and __inject_sigp_stop() is called from do_inject_vcpu() which in turn is always called holding a spinlock, which is obviously an issue. Fix this by returning -EWOULDBLOCK from __inject_sigp_stop(), and adding a bool flag to indicate whether a store status is needed. The callers of do_inject_vcpu() are modified to pass the pointer to the bool flag; whenever a Store Status operation is needed, the callers can now perform it outside the spinlock. Opportunistically refactor kvm_s390_set_irq_state() to use scoped_guard() and __free(). Fixes: 6cddd432e3da ("KVM: s390: handle stop irqs without action_bits") Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> [ Added Fixes tag while picking -- Claudio ] Message-ID: <20260812104436.109741-7-imbrenda@linux.ibm.com>
2026-08-12KVM: s390: Fix pgste_get_trylock_multiple()Claudio Imbrenda1-5/+2
In case of failure, pgste_get_trylock_multiple() will attempt to unlock the locked PGSTEs based on whether the PCL is set. In some circumstances this can lead to unlocking PGSTEs that were locked by other threads. Fix by unlocking the amount of PGSTEs that were actually locked, ignoring the PCL bit in the array. Fixes: 94fd9b16cc67 ("KVM: s390: KVM page table management functions: lifecycle management") Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260812104436.109741-6-imbrenda@linux.ibm.com>
2026-08-12KVM: s390: Fix get_all_floating_irqs()Claudio Imbrenda1-1/+6
When attempting to report all pending floating interrupt to userspace, the GISA IPM bits are atomically tested and cleared, and the corresponding interrupt description is written in the output buffer. If the output buffer is too small, an error is returned to userspace, but the GISA IPM bits are now lost. Moreover, the contract of KVM_DEV_FLIC_GET_ALL_IRQS, which is the only path to get_all_floating_irqs(), states that: > All interrupts remain pending, i.e. are not deleted from the list of > currently pending interrupts. Fix by non-destructively testing for the GISA IPM bits. Fixes: 24160af6cb28 ("KVM: s390: add GISA interrupts to FLIC ioctl interface") Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260812104436.109741-4-imbrenda@linux.ibm.com>
2026-08-12KVM: s390: Use srcu in kvm_arch_vcpu_unlocked_ioctl()Claudio Imbrenda1-2/+4
kvm_arch_vcpu_unlocked_ioctl() is called without further locks held, but kvm_s390_inject_vcpu(), which is called from there, needs either the kvm->srcu or the slots lock. Fix by taking the kvm->srcu in kvm_arch_vcpu_unlocked_ioctl(). Fixes: ba5c1e9b6cee ("KVM: s390: interrupt subsystem, cpu timer, waitpsw") Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260812104436.109741-3-imbrenda@linux.ibm.com>
2026-08-12KVM: s390: Properly handle NULL pointer in dat_cond_set_storage_key()Claudio Imbrenda1-1/+4
Some callers pass NULL as oldkey. Calling page_cond_set_storage_key() will cause that NULL pointer to get dereferenced. Fix by checking for NULL and assigning the pointer to a dummy local variable to avoid crashes. Fixes: 8e03e8316eb2 ("KVM: s390: KVM page table management functions: storage keys") Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260812104436.109741-2-imbrenda@linux.ibm.com>
2026-08-12KVM: s390: Restore sigset on error pathChristian Borntraeger1-2/+4
kvm_sigset_activate() installs vcpu->sigset via sigprocmask() and stashes the caller's mask in current->real_blocked; only kvm_sigset_deactivate() restores it. For KVM_RUN on a STOPPED vcpu the error path will not restore the userspace mask. Re-arrange the error handling to also restore the signal mask. Fixes: 6352e4d2dd9a3 ("KVM: s390: implement KVM_(S|G)ET_MP_STATE for user space state control") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260811153738.206885-5-borntraeger@linux.ibm.com>
2026-08-12KVM: s390: pv: Fix rc/rrc offset for PVM_DUMPChristian Borntraeger1-1/+1
The rc/rrc value is copied to the cmd location of the cmd in the kvm_pv_cmd structure. Fix the offset. Fixes: 8aba09588d2a ("KVM: s390: Add CPU dump functionality") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260811153738.206885-4-borntraeger@linux.ibm.com>
2026-08-12KVM: s390: vsie: zero stale crypto bitsChristian Borntraeger1-0/+1
When shadowing crypto access bits from a format0 apcb (crycb 0 or 1), the bits 64..255 are unchanged from whatever is in the vsie page in the crycb and thus in the apcb. This gives a nested guest potential access to a device no longer available. Zero out the remaining bits. Fixes: 6b79de4b056e ("KVM: s390: vsie: allow guest FORMAT-1 CRYCB on host FORMAT-2") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260811153738.206885-3-borntraeger@linux.ibm.com>
2026-08-12KVM: s390: keyop: use mmu_lock to read gmap->asceChristian Borntraeger1-1/+2
Every other dat_* consumer in this file (kvm_s390_get_skeys, set_skeys, get_cmma_bits, set_cmma_bits, MEM_CLR_CMMA, kvm_s390_fixup_prefix, kvm_test_age_gfn, kvm_age_gfn) reads kvm->arch.gmap->asce *inside* the mmu_lock read-side. keyop is the only outlier. gmap->asce is mutated under write_lock(mmu_lock) by gmap_set_limit() and keyop might use a stale asce value for walking as KVM_S390_KEYOP and KVM_S390_VM_MEM_LIMIT_SIZE can run concurrently. This can result in memory corruption. Fixes: 0ee4ddc1647b ("KVM: s390: Storage key manipulation IOCTL") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260811153738.206885-2-borntraeger@linux.ibm.com>
2026-08-11KVM: s390: Fix memory corruption by not reinjecting CK machine checksChristian Borntraeger1-16/+8
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: 4d62fcc0b692 ("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>
2026-08-11KVM: s390: Fix length check __import_wp_info()Christian Borntraeger1-1/+1
struct kvm_hw_breakpoint::len is a __u64 that is fully controlled by user space. This is then assigned to wp_info->len, which is an int. The bounds check is done on the truncated value while the allocation uses the untruncated one: wp_info->len = bp_data->len; [...] if (wp_info->len < 0 || wp_info->len > MAX_WP_SIZE) return -EINVAL; wp_info->old_data = kmalloc(bp_data->len, GFP_KERNEL_ACCOUNT); Use the validated value for the allocation as intended. Without this fix userspace can trigger >4GB allocations which will fail and result in a WARN due to MAX_PAGE_ORDER. Fixes: 27291e2165b6 ("KVM: s390: hardware support for guest debugging") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260805110455.7200-9-borntraeger@linux.ibm.com>
2026-08-11KVM: s390: Free guest debug data on vcpu destroyChristian Borntraeger1-0/+1
kvm_s390_clear_bp_data() is only called from kvm_arch_vcpu_ioctl_set_guest_debug(), i.e. when user space changes or disables debugging. A vCPU that is destroyed while hardware breakpoints are still armed - the normal case when the VMM just exits or crashes - leaks hw_bp_info, hw_wp_info and all old_data buffers, since generic KVM frees the vCPU right after kvm_arch_vcpu_destroy(). That is bounded by MAX_BP_COUNT entries, so roughly 8 KiB per vCPU, but it is unbounded over VM lifetimes. The allocations are GFP_KERNEL_ACCOUNT, so the charge also outlives the exiting process and pins dying memcgs. Fix by clearing the debug data on vCPU destruction. Calling it unconditionally is fine: struct kvm_vcpu is zero allocated, so for a vCPU that never enabled debugging the counters are 0 and the pointers NULL. Fixes: 27291e2165b6 ("KVM: s390: hardware support for guest debugging") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260805110455.7200-8-borntraeger@linux.ibm.com>
2026-08-11KVM: s390: Take srcu when importing watchpoint dataChristian Borntraeger1-2/+4
__import_wp_info() backs up the original guest memory contents of a watchpoint with read_guest_abs(), which is kvm_read_guest() and therefore resolves the memslot via __kvm_memslots(). That requires kvm->srcu (or kvm->slots_lock) to be held, otherwise a concurrent memslot update can free the memslots array under us once its SRCU grace period has elapsed. As this is not fast path, following lock ordering (mutex first, then srcu) take the big hammer and hold the srcu for the full import. Fixes: 27291e2165b6 ("KVM: s390: hardware support for guest debugging") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260805110455.7200-7-borntraeger@linux.ibm.com>
2026-08-11KVM: s390: Fix old_data leak in guest debug error pathChristian Borntraeger1-1/+5
__import_wp_info() allocates a per-watchpoint old_data buffer to back up the original guest memory contents. If a later watchpoint of the same KVM_SET_GUEST_DEBUG request fails to import, kvm_s390_import_bp_data() jumps to the error label, which frees the wp_info array but not the old_data buffers of the entries that were imported successfully. Up to MAX_BP_COUNT - 1 buffers of up to MAX_WP_SIZE bytes are leaked per failed request, and the request can be repeated. Create error handling for cleaning up all created old_data memory areas. Fixes: 27291e2165b6 ("KVM: s390: hardware support for guest debugging") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260805110455.7200-6-borntraeger@linux.ibm.com>
2026-08-11KVM: s390: Fix memory leak in guest debug handlingChristian Borntraeger1-0/+1
bp_data is freed only for the error case by kfree(bp_data). Every successful KVM_SET_GUEST_DEBUG will leak bp_data. Fixes: 27291e2165b6 ("KVM: s390: hardware support for guest debugging") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260805110455.7200-5-borntraeger@linux.ibm.com>
2026-08-11KVM: s390: Zero initialize irq in reinject_machine_checkChristian Borntraeger1-1/+1
kvm_s390_reinject_machine_check() fills cr14, mcic, ext_damage_code and failing_storage_address of the on-stack struct kvm_s390_irq, but struct kvm_s390_mchk_info also has a pad word and a 16 byte fixed_logout array. struct mcck_volatile_info carries no logout data, so there is nothing to copy there and both stay whatever was on the stack. __inject_mchk() then memcpy()s fixed_logout into the vcpu local interrupt state unconditionally. This will reach the guest during deliver and userspace during migration. Reflecting zeroes is the correct behaviour here, as KVM has no logout data for a reinjected machine check. This needs a host machine check while the cpu is in SIE so not trivial to trigger. Fixes: 4d62fcc0b692 ("KVM: s390: Inject machine check into the guest") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260805110455.7200-4-borntraeger@linux.ibm.com>
2026-08-11KVM: s390: Zero initialize data structures for inject_pfault_tokenChristian Borntraeger1-2/+2
__kvm_inject_pfault_token() only sets .type and .u.ext.ext_params2 of the on-stack struct kvm_s390_irq but the full ext substructure is copied into the cpu local variable on inject. ext_params and pad contain stale stack values. Interrupt delivery only uses ext_params2, so nothing leaks to the guest, but a host user can use the migration ioctls to get to the data. Fix by zero-initializing the irq struct. Do the same for the inti data structure. Fixes: 383d0b050106 ("KVM: s390: handle pending local interrupts via bitmap") Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260805110455.7200-3-borntraeger@linux.ibm.com>
2026-08-11KVM: s390: Remove user triggerable WARN_ONChristian Borntraeger1-1/+1
pin_map_page() fails legitimately whenever the userspace mapping behind the adapter route has gone away, e.g. when the VMM unmaps that memory. As this can happen without a kernel programming error, remove the WARN_ON. Fixes: 1e95e3bc6b05 ("KVM: s390: Enable adapter_indicators_set to use mapped pages") Cc: Douglas Freimuth <freimuth@linux.ibm.com> Cc: Matthew Rosato <mjrosato@linux.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Douglas Freimuth <freimuth@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260805110455.7200-2-borntraeger@linux.ibm.com>
2026-08-10KVM: s390: vsie: Create constant SCB_ALIGNMENT_SHIFTChristoph Schlameuss1-4/+5
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>
2026-08-10KVM: s390: vsie: Assert crycb alignment in vsie_pageChristoph Schlameuss1-0/+1
The crypto control block address is required to have double word alignment. Add a static_assert to enforce correct alignment. Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> [borntraeger@linux.ibm.com: improve commit message] Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-10KVM: s390: vsie: Assert mcck_info offset in vsie_pageChristoph Schlameuss1-4/+2
Ensure that the backup info for machine check is the same offset as that in struct sie_page! With the assertion in place we do not need the comment anymore. Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-10KVM: s390: vsie: Convert shift to phys_to_pfn()Christoph Schlameuss1-1/+1
Make the code slightly more readable by using phys_to_pfn instead of an open coded shift. Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com> [borntraeger@linux.ibm.com: improve commit message] Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-10KVM: s390: vsie: Remove duplicate assertionChristoph Schlameuss1-1/+0
Remove useless BUILD_BUG_ON() checking the size of struct vsie_page. This is already covered by a static_assert at the struct vsie_page definition. Fixes: e38c884df921 ("KVM: s390: Switch to new gmap") Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com> [borntraeger@linux.ibm.com: improve commit message] Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-10KVM: s390: Remove double 64bscao feature checkChristoph Schlameuss1-2/+1
sclp.has_64bscao is already verified in the guard clause a few lines above this. So we cannot reach this code if it is not true. Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com> Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
2026-08-05KVM: s390: Remove cond_resched() callsHeiko Carstens5-18/+7
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 7dadeaa6e851 ("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>
2026-08-03KVM: s390: Fix cleanup in kvm_s390_pv_create_cpu()Claudio Imbrenda1-20/+21
If creating a protected vCPU in kvm_s390_pv_create_cpu() fails, kvm_s390_pv_destroy_cpu() was called, which checks whether the vCPU has a PV handle and exits doing nothing otherwise. At that point, due to not having created the protected vCPU, the PV handle will not be set, and kvm_s390_pv_destroy_cpu() will do nothing, thus leaking the allocated memory. Fix by factoring out the code to free and reset a PV vCPU; call it from kvm_s390_pv_destroy_cpu() and kvm_s390_pv_create_cpu(). Opportunistically fix the return value of kvm_s390_pv_destroy_cpu() in case of errors: return -EIO instead if EIO. Fixes: d4074324b07a ("KVM: s390: pv: avoid double free of sida page") Reviewed-by: Steffen Eiden <seiden@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260803124040.126471-14-imbrenda@linux.ibm.com>
2026-08-03KVM: s390: Fix ordering when adding to SCAClaudio Imbrenda1-1/+1
When adding a new vCPU to the SCA area, the validity bit in the MCN was set before the pointer to the state description, potentially allowing for a race. Fix by setting the pointer before setting the bit. Fixes: 14542a0a54c5 ("KVM: S390: Remove sca_lock") Reviewed-by: Steffen Eiden <seiden@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Message-ID: <20260803124040.126471-13-imbrenda@linux.ibm.com>