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4 daysMerge tag 'hyperv-next-signed-20261028' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv updates from Wei Liu: - Update to documents and code comments (Michael Kelley) - Harden Vmbus (Kameron Carr) - Rework MSHV driver page deposit logic (Mukesh Rathor) - Vmbus kexec bug fix (Shradha Gupta) - Miscellaneous bug fixes (Daehyeon Ko, Jiale Yao, Sasha Levin) * tag 'hyperv-next-signed-20261028' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: Drivers: hv: Remove leftover support for old Hyper-V versions mshv: Remove unused *_old memory deposit functions mshv: Redesign hypervisor memory deposit logic mshv: Rename memory deposit memory functions to _old mshv_vtl: reject poll files with multiple waitqueues mshv_vtl: detach poll waiter on POLLFREE mshv_vtl: initialize poll file mutex before device registration Documentation: hyperv: Update information on guest CPU offlining Documentation: hyperv: Remove support for guests on Hyper-V 2012/2012R2 Drivers: hv: Run VMBus kexec cleanup from syscore shutdown kexec: Add helper to report an active kexec reboot tools: hv: remove unused rte_smp_mb() Documentation: hyperv: Update documentation for sending VMBus packets Drivers: hv: vmbus: Check ACPI companion before use Documentation: hyperv: Describe validation of the ring buffer indices Drivers: hv: vmbus: Keep the ring byte counts sane for a bad index Drivers: hv: vmbus: Compute ring byte counts from a caller-held snapshot Drivers: hv: vmbus: Use *_ONCE() to access shared ring buffer indices Drivers: hv: vmbus: Bounds check the shared ring buffer indices
10 daysMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "ARM: - pKVM state isolation: years after pKVM started being enabled upstream, we finally get the basics in the form of state isolation. The vcpu state is now off-limit for the host for protected VMs - pKVM also grows a hypervisor-private memory allocator, allowing it to deal with sub-page allocation, much like everywhere else - pKVM also lands a trace_printk() equivalent, which hopefully will make debugging a bit easier - First shot at annotating portions of the KVM/arm64 code to be extracted and built on s390. The real fun is yet to come - Allow pre-faulting of stage-2 canonical mappings from userspace, joining x86 and s390 in implementing this feature - Add a reverse mapping infrastructure for shadow stage-2, significantly improving performance when MMU notifiers kick in, and avoiding full unmap of all shadow tables for this VM - Next step of GICv5 enablement, adding support for the IRS block, and providing both SPI and LPI support. This is the first point where KVM/arm64 can support an SMP GICv5 guest - As a preliminary to eventually enabling CCA, add a bunch of infrastructure to KVM/arm64, splitting some of the basic operations into individual backends (normal VM, normal pKVM VM, protected pKVM VM). This allows CCA to later slot in without polluting the rest of KVM with its firmware-driven nonsense - Make ID registers immutable from the point where a vcpu is able to run, even if it fails to run. This prevents KVM from sampling untrusted values - Restore some type checking to the EL2 object. KVM/arm64 originally had some strong type checking between the kernel and the EL2 object, but lost it along the way when the private hypercall interface was (somewhat pointlessly) converted to SMCCC. Type checking is back, syscall style, and with added sparse goodies - Expand the FFA support to FFA_NOTIFICATION_*, and add some sanitisation of the protocol that pKVM relays to the "trusted" runtime - Make GICv3 RD assignment more robust to userspace nonsense - Convert the remaining MMU fault handler backends to kvm_s2_fault_vma_info and co., fixing a number of bugs in the process - Fix the SError/SEA selftests to be both more robust and less braindead - Fix a smattering of documentation bugs, some of them as a result of our AI friends spitting out credible assertions based on non-existing symbols - The usual collection of low impact bug fixes (SMCCC, timers, PMU) Loongarch: - Add separate vmid support - Simplify MSI interrupt injection - Add crash hypercall support - Allow to set pv_feature until vCPU run - Enable HW page table walk automatically in selftests s390: - rework page allocation for secure guest variable storage - Selftests and documentation improvements - Replace get_zeroed_page with kzalloc - Fix corner cases of floating interrupt injection - Initial arm64 on s390 support x86: - Clean up the handling of vcpu->arch.xen.long_mode to be consistent and correctly handle 32-bit/64-bit alignment, and various other bug fixes have accumulated over the months since v1 - Grab KVM's SRCU "lock" in kvm_zap_gfn_range() to fix a recurring bug where callers fail to do so - Fix a variety of issues in the pre-fault code that are mostly benign in the current code base, but will show up in big ways if/when the pre-faulting logic is used to implementing prefetch-on-fault for the TDP MMU - For PREEMPT_RT=y kernels, drop the rmaps' individual bit-spinlock and just walk the rmaps' with mmu_lock taken. On the write side (which always uses mmu_lock), the bit-spinlock was assuming that preemption was disabled, but that is *not* true when rwlocks become sleepable - Prepare a memory_fault exit (paired with -EFAULT) when KVM hits an error PFN, e.g. so that userspace can resolve transient issues instead of killing the guest. Convert a variety of WARN()+EFAULT paths into KVM_BUG_ON()+EIO so that KVM can hard commit to filling memory_fault on -EFAULTs that occur in the page fault path - Fix a NX hugepage un-accounting bug where KVM would always uncharge the shadow MMU, even when handling TDP MMU pages - Mask off the address space ID when checking for illegal usage of kvm_set_internal_memslot() to prevent false negatives on the sanity check - Explicitly zero reserved flags when delivering a SynIC message to avoid leaking a byte of stack information to the guest - Rework TDX's handling of the canonical MMU root level to not rely on userspace to fill CPUID correctly, as doing so lets userspace trivially trigger a KVM_BUG_ON() - Reject KVM_SET_NESTED_STATE if userspace "restores" L1 with EFER.LMA=1 && EFER.LME=0, which confuses KVM into trying to configure an 64-bit MMU without PAE - Ignore EFER.LMA (clear it from KVM's cached save state) if EFER.LME=0 when preparing L2 state, to fix another way to confuse KVM's MMU (and because real hardware also ignores EFER.LMA) - Improve KVM's sanity checks for a misconfigured MMU to (hopefully) detect all of the ways KVM can botch EFER.LMA vs. CR4.PAE - Remove the "full" out-param from kvm_x86_ops.flush_tlb_gva() as the param is only used to avoid what effectively amounts to a single memory write - Fix a mostly-benign bug where KVM can write through a guest's read-only mapping due to not checking the error code when expediting emulated MMIO page faults - Honor the guest's view of the "EFER.LMSLE must be zero" defeature so that userspace can provide migration compatibility between Rome and Milan+ - Pend a KVM_REQ_EVENT request when an exception is morphed into a nested VM-Exit, otherwise KVM can fail to actually deliver the nested VM-Exit, e.g. when injecting a page fault - Add support for PML on SVM - Add support for virtualizing Bus Lock Detect on SVM, and fix a number of DR6 bugs and warts along the way - Fix a variety of warts in KVM's handling of guest TSC, kvmclock, and timekeeping in general, as a (big) first step towards addressing several longstanding problems with the kvmclock implementation. Most notably, fix a precision issue where get_kvmclock_ns() computed the clock from the *host* TSC without applying guest TSC scaling, causing systemic drift from the values the guest computes from its own TSC - Rip out KVM's shadow timekeeping structures, now that ktime snapshots are powerful enough to replace it - Misc fixes and cleanups x86 (AMD): - Fix a benign-in-practice bug where KVM unintentionally sets a non-zero error code when delivering exceptions to SEV-ES+ guests - Force a new ASID in both VMCBs on pCPU migration to fix a bug where KVM can run a VMCB with a stale ASID due to the tracking being per-CPU, not per-VMCB - Return INVALID_INPUT to the guest instead of exiting to userspace with -EIO if KVM can't access "guest request" buffer, i.e. try to keep the guest alive if the guest or userspace goofs x86 (Intel): - Enable Notify VM-Exits (now called Instruction Timeout in the SDM) and Bus Lock VM-Exits for TDX guests when they're enabled by userspace (KVM forgot to wire up the TDX Module knobs) - Move all common (between VMX and TDX) APIs/helpers to common.h/main.c, and change all namespace prefixes from "vmx" to "vt" - Fix a thankfully benign bug (due to other areas of KVM being hardened) where userspace can bypass INIT_MEM_REGION's address wrap check by providing a nr_pages that will overflow a u64 when converted to bytes, and fix an also- benign off-by-one bug in the check (inclusive vs. exclusive) - Set the vmcs.GUEST_ACTIVITY_STATE back to ACTIVE when userspace sets KVM's mp_state to anything other than HALTED, e.g. so that a vCPU doesn't get stuck in HLT if userspace emulates RESET guest_memfd: - Take the invalidate lock when unbinding a dying file to fix a race with kvm_gmem_invalidate_end() that results in KVM leaving the MMU invalidation count elevated. Not taking the lock in the first place was pure misguided paranoid - When binding a memslot, purge the bindings if storing the new memslot fails, as Xarray's "store range" API can subtly fail partway through - Establish memslot<=>guest_memfd bindings *after* the memslot is ready, as the memslot becomes reachable the instant the binding is installed - Don't grab a page refcount when reloading an SNP VMSA and stop returning a "struct page" from guest_memfd's PFN lookup altogether, to ensure that KVM doesn't hold any unnecessary refcounts (the lifetime of the page is ensured by MMU notifiers and similar hooks). Preventing unnecessary refcounts greatly simplifies supporting in-place SHARED=>PRIVATE conversions - Add support for in-place PRIVATE<=>SHARED conversion, i.e. allow a single guest_memfd instance to be used for both PRIVATE and SHARED variations of CoCo guests' memory (though not at the same time). This eliminates the need to double allocate guest memory for TDX and SNP, and is basically a hard requirement for pKVM, which relies on being able to preserve memory contents on conversions - Hack-a-fix a deadlock bug in ->error_remove_folio() by returning -EBUSY if the filemap invalidate lock is contended. Punt on a proper fix for the moment, as a proper fix likely involves reworking truncate_error_folio() - Add a pile of selftests for in-place conversions - Misc guest_memfd cleanups Generic: - Move some configuration items to preprocessor symbols, to help with arm-on-s390's need to compile the same code twice with different values - Allow KVM implementations to choose alternative device names, also for s390's support of ARM virtualmachines - Switch the KVM-VFIO interface and external consumers over to standard file-based reference counting, eliminating all external KVM symbol exports Selftests: - Rework KVM selftest's handling of memory regions all so that PPC can force its page table allocations to be naturally aligned - PPC support - Fix emulation of VMPTRST and VMPTRLD when eVMCS is in-use to match real Hyper-V's behavior - Saturate L2's TSC frequency if stacking L1 and L2 scaling multipliers exceeds what hardware supports, as attempting to run L2 with an illegal multiplier will either cause VM-Entry to fail (VMX) or trigger a #GP when writing MSR_AMD64_TSC_RATIO (SVM). The #GP is thankfully benign in the grand scheme as even "unsafe" WRMSRs have exception fixup - Rework KVM selftest's handling of memory regions so that PPC can force its page table allocations to be naturally aligned - Clean up selftest's VMX instruction helpers, and drop an absurd number of completely useless return values, e.g. functions that unconditionally return %true and then have every caller assert success - Add selftests support for Zhaoxin CPUs - Overhaul the TSC scaling test to add a regression test for the saturation behavior, and to increase its coverage in general - Fix selftests usage various NUMA syscalls to account for an undocumented, but known since 2007, off-by-one kernel bug. Add helpers to try and avoid re-introducing the same flaws in the future - Automatically run xAPIC IPI migration test (between NUMA nodes) when possible, as the entire point of the test is verify KVM's handling of page migration of the APIC backing page - Misc cleanups" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (506 commits) KVM: always make in-place conversion a compile-time constant when possible KVM: x86: leave the legacy private attribute in for TDX and SEV KVM: split CONFIG_KVM_PRIVATE_MEMATTR_VM out of KVM_VM_MEMORY_ATTRIBUTES selftests: kvm: remove useless comma operator arm64: Use proper include variant MAINTAINERS: Add entry for ARM on s390 KVM KVM: s390: arm64: Integrate arm on s390 KVM: s390: arm64: Implement basic page fault handler KVM: s390: arm64: Implement vCPU IOCTLs KVM: s390: arm64: Implement vm/vcpu create destroy KVM: s390: arm64: Implement required functions KVM: s390: Add basic arm64 kvm module s390/hwcaps: Report SAE support as hwcap KVM: s390: arm64: Introduce host definitions s390: Introduce Start Arm Execution instruction KVM: s390: Use arm64 code s390/tools: Use arm64 headers KVM: s390: Use dedicated function for migration mode s390/Kconfig: remove PCI dependency from HAS_IOMEM KVM: s390: Kick PV cpus at the right time for service irqs ...
10 daysMerge tag 'modules-7.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux Pull module updates from Petr Pavlu: - Ignore local labels and mapping symbols during module load These symbols were already ignored during kallsyms address-to-symbol lookups. Filter them out earlier during module loading to reduce lookup overhead and prevent them from appearing in /proc/kallsyms. - Fix potentially incorrect access of SetOnce<T> when setting Rust module parameters. - Fix a potential read of an uninitialized count when printing taint information for unloaded modules. - Allocate the kmod argument array using kmalloc_array() in preparation for conversion to type-aware allocators. - Clean up includes in linux/kmod.h Add explicit includes of linux/umh.h to files that use usermode helpers. Then clean up the #include list in linux/kmod.h, notably removing the compatibility linux/umh.h include. - Remove the error-injection.h include from linux/module.h Add explicit includes of linux/error-injection.h to files that use the ALLOW_ERROR_INJECTION() macro and currently rely on it being provided indirectly via linux/module.h. Then remove the unnecessary linux/error-injection.h include from linux/module.h. - Replace __MODULE_STRING() with __stringify() in various drivers in preparation for removing the former macro. * tag 'modules-7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux: drivers: Replace __MODULE_STRING() with __stringify() module: Fix uninitialized count read of unloaded taint tracking record rust: module_param: Fix potentially incorrect access of `SetOnce<T>` module: Remove the error-injection.h include from linux/module.h drm/xe: Include error-injection.h for ALLOW_ERROR_INJECTION() drm/i915: Include error-injection.h for ALLOW_ERROR_INJECTION() syscalls: Include error-injection.h for ALLOW_ERROR_INJECTION() net: Include error-injection.h for ALLOW_ERROR_INJECTION() block: Include error-injection.h for ALLOW_ERROR_INJECTION() module: Bring includes in linux/kmod.h up to date time/jiffies: Include linux/sysctl.h for proc_int_u2k_conv_uop(), ... umh, treewide: Explicitly include linux/umh.h where needed modules/kmod: Allocate argv with kmalloc_array() module/kallsyms: Ignore local labels and mapping symbols during module load module/kallsyms: Refactor current symbol filtering into is_core_symbol() module/kallsyms: Rename is_mapping_symbol() to is_ignored_kernel_symbol()
10 daysMerge tag 'hardening-v7.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: - Provide kmalloc_obj*-style API for devm_kmalloc() - Improve seq_buf API for saner C String handling with several bug fixes along the way (Kees Cook, Bill Wendling) - Overflow helper readability improvements (Bill Wendling) - Unexport native_write_cr4() (Dennis Chen) - um: fix CONFIG_GCOV for built-in code (Johannes Berg) - Improve stackinit test coverage (Justin Stitt) - KMSAN: fix memset() when using fortify-source, again (Arnd Bergmann) - lkdtm: use kmalloc() instead of __get_free_page (Mahad Ibrahim) - signalfd: don't dequeue the forced fatal signals (Oleg Nesterov) - Fix randstruct to recognize new container_of() behavior - coccinelle: kmalloc_obj: Convert multi-byte integral allocations too - Fix a couple remaining allocation return type mismatches * tag 'hardening-v7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (29 commits) overflow: Match arithmetic in both parts of __builtin_choose_expr lkdtm: Make UNSET_SMEP built-in-only and unexport native_write_cr4() extcon: realtek: Remove const from type_c_cfg allocation type coresight: cti: Add const to con_groups allocation type docs: core-api: Document the seq_buf API nvdimm: ndtest: Return the string length from flags_show() powerpc/papr_scm: Return the string length from the sysfs show functions seq_buf: Add seq_buf_init_append() bpf: Remove dead newline stripping from format_disasm_line() seq_buf: Add seq_buf_terminate() seq_buf: Add seq_buf_strlen() seq_buf: Clear what a writer did not claim when a seq_buf overflows seq_buf: Copy what fits when seq_buf_puts() and seq_buf_putmem() overflow scsi: lpfc: Print rx monitor records straight into the seq_buf seq_buf: Do not pop from an overflowed seq_buf seq_buf: Do not print an empty line from an overflowed seq_buf_do_printk() .get_maintainer.ignore: Add Kees Cook devres: Provide kmalloc_obj*-style API for devm_kmalloc mm: Move default_gfp() into gfp_types.h kunit/stackinit: Clean up XFAIL under instrumentation ...
11 daysMerge tag 'driver-core-7.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core Pull driver core updates from Danilo Krummrich: "Core: - Add TAINT_FORCED_BIND to taint the kernel and driver module before manual sysfs bind/unbind operations; make add_taint_module() available to driver core and update taint decoding tools and documentation - Constify device_show/store_*() attribute parameters and adapt x86 MCE and perf users to prepare for const dev_ext_attribute instances - Fix UAF in NUMA access node registration failure handling by dropping the device reference with put_device() instead of directly freeing the node debugfs: - Make debugfs_create_str() read-only to eliminate double-free races between concurrent writers; reject writable modes; convert interconnect and SoundWire users to local file operations with mutex-protected strings kobject: - Fix out-of-bounds access in kobject_action_type() when parsing action strings containing embedded NUL bytes - Fix the kobject_set_name() reference in kset_register() kernel-doc Rust: - DMA: - Tie Coherent, CoherentBox and CoherentHandle to the device's bound lifetime to prevent retaining DMA allocations beyond driver unbind; propagate the lifetime through nova-core and the DMA sample driver - I/O: - Require explicit base types for registers and replace relative registers with typed subregion projections; reimplement register!() as a proc macro, support registers using existing types without inline bitfields, and convert nova-core, Tyr and the PCI sample; add AsRepr/AsReprMut and transmute helpers with deferred size checks for representation conversions - Wrap ResourceSize in a transparent newtype with explicit conversions, including checked conversion to usize - PCI: - Add typed PCIe extended capability lookup and SR-IOV accessors for the First VF Offset and decoded VF BAR addresses and widths, keeping raw SR-IOV registers private to preserve PCI core ownership of their state - scatterlist: - Honor the device's maximum segment size as well as the DMA mapping limit when constructing SG tables - Return u32 from SGEntry::dma_len() to match the C segment length type - misc: - Validate auxiliary DeviceId name length explicitly to improve compile-time diagnostics for oversized device ID table entries - Drop unnecessary 'static bounds from debugfs ScopedDir file creation methods to support data containing non-'static references, including DMA buffers Misc: - Add Johan Hovold as driver core maintainer - Simplify platform_device_alloc() by returning early on allocation failure - Fix typos in driver core and kernfs comments" * tag 'driver-core-7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (41 commits) rust: pci: add extended capability and SR-IOV support kobject: Fix the kobj_set_name reference in kset_register() kernel-doc rust: io: convert ResourceSize into a transparent newtype rust: scatterlist: return u32 from SGEntry::dma_len() MAINTAINERS: add myself as driver core maintainer debugfs: make debugfs_create_str() read-only soundwire: debugfs: replace writable string helper interconnect: debugfs: replace writable string helper docs: admin-guide: Handle TAINT_FORCED_BIND when parsing /proc/sys/kernel/tainted driver core: platform: Simplify platform_device_alloc() kobject: fix out-of-bounds access in kobject_action_type() rust: scatterlist: honor the device's maximum segment size driver core: add TAINT_FORCED_BIND for when userspace manually messes with devices and drivers module: fix up documentation for add_taint() and add_taint_module() module: pull out add_taint_module() to be public driver core: Constify the signature of device_show/store_*() drivers: perf: Use __DEVICE_ATTR() macro to initialize dev_ext_attribute x86/mce: Use __DEVICE_ATTR() macro to initialize dev_ext_attribute rust: auxiliary: validate DeviceId name length driver core: fix typos in comments ...
12 daysDrivers: hv: Run VMBus kexec cleanup from syscore shutdownShradha Gupta
ARM64 Hyper-V guests do not run the VMBus kexec cleanup before secondary CPUs are stopped. Consequently, the old VMBus connection and SynIC state remain active when the kexec kernel starts. Run the VMBus kexec handler from the existing VMBus syscore shutdown callback. syscore_shutdown() runs after device shutdown and before machine shutdown, while all CPUs needed by the SynIC CPU hotplug teardown are still available. Guard the callback with kexec_is_in_progress() so normal restart, halt, and poweroff paths are unchanged. Use the same path on x86 and remove the architecture-specific handler pointer and the weak setup/remove interfaces. VMBus teardown now precedes hv_stimer_global_cleanup() on x86. The new x86 ordering relies on commit be0cfab740e5 ("clocksource: hyper-v: Remove support for stimer interrupts in message mode"), which removed the synthetic timer's dependency on VMBus message delivery. Older kernels that retain message-mode stimer interrupts must preserve the existing x86 ordering and therefore require an ARM64-specific backport. Document the VMBus cleanup path and its position in shutdown ordering. Fixes: 9bbb888824e3 ("arm64: hyperv: Initialize hypervisor on boot") Link: https://lore.kernel.org/all/20260814093133.3191250-1-shradhagupta@linux.microsoft.com/ Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Suggested-by: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com> Reviewed-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Bradley Morgan <brads@mainlining.org> Reviewed-by: Naman Jain <namjain@linux.microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
13 daysMerge tag 'sched-core-2026-10-18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Kconfig updates: - Simplify PREEMPT_DYNAMIC (Mark Rutland) Fair scheduler updates: - Remove redundant RUN_TO_PARITY check (Elif Topuz) - Declare augmented callbacks per field, fix rb_add_augmented_cached() descent (Yiwei Lin, Peter Zijlstra) - Restart fair hrtick after same-task repicks (Shubhang Kaushik) - Improve the scheduling latency of short slice tasks (Vincent Guittot) Deadline/RT scheduler updates: - Check start_dl_timer expiry with ktime_before() (Liang Hao) - irq_work: CPU-hotplug improvements on PREEMPT_RT (Sebastian Andrzej Siewior) Energy-aware scheduling updates: - Implement the steal_governor, introduce preferred CPUs and steal-driven vCPU backoff (Shrikanth Hegde) Multi-processor load-balancing updates: - Enable preferred SMT siblings on NVIDIA Olympus (Andrea Righi) - Randomize equally shallow idle CPU picks (Christian Loehle) - Remove redundant core_sched_seq (Hui Su) Cache-aware scheduling updates: - Avoid publishing partial LLC utilization (Jemmy Wong) NUMA-balancing updates: - Reset NUMA fault locality after scan period update (Eric Kim) Proxy execution updates: - Ongoing work to implement sleeping owner handling for proxy execution (John Stultz, Vasily Gorbik) - Preparatory steps to make sched_ext compatible with proxy execution (Andrea Righi) Scheduler infrastructure updates & fixes: - Remove the RCU wait from PSI trigger destruction (Shakeel Butt) - Avoid modifying wait-entry on failed priority registration (Hui Su) - Use the new static key API for sched_feat (Hongyan Xia) - Convert paravirt_steal to new static key APIs (Hongyan Xia) - cputime: Don't account idle time twice after dyntick-idle (Stian Halseth) Scheduler debugging updates: - Set TIF_NEED_RESCHED before calling __trace_set_need_resched() (Sechang Lim) - Fix context analysis errors in non-preferred CPU push (Shrikanth Hegde) Misc cleanups and fixes by Christian Loehle, Shubhang Kaushik, Thomas Huth and Vladimir Zapolskiy" * tag 'sched-core-2026-10-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits) sched: Replace nr_iowait_cpu() with a bool accessor Revert "sched/fair: Remove dead code on enqueue_task_fair()" sched/cache: Avoid publishing partial LLC utilization sched/cputime: Don't account idle time twice after dyntick-idle sched/psi: Remove the RCU wait from trigger destruction sched/eevdf: Remove redundant RUN_TO_PARITY check sched/wait: Avoid modifying entry on failed priority registration rbtree_test: Use rb_add_augmented_cached() for the cached augmented test rbtree: Update augmented data on the way down in rb_add_augmented_cached() rbtree: Declare augmented callbacks per field with RB_AUG() rbtree_test: Use rb_add() and rb_add_cached() for the basic tests smpboot: Don't park the thread if work is pending irq_work: Flush lazy work CPU down on PREEMPT_RT irq_work: Update a comment regarding CPU hotplug invocation sched/topology: Add asymmetric SMT packing override sched/fair: Honor asymmetric SMT priority in idle selection sched: Set TIF_NEED_RESCHED before calling __trace_set_need_resched() sched/core: Fix context analysis errors in non-preferred CPU push virt/steal_governor: Enable the driver virt/steal_governor: Implement steal_governor policy loop ...
13 daysMerge tag 'x86_microcode_for_7.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loader update from Dave Hansen: "This one simply brings the 'old microcode' list up to the May 2026 release. This continues the policy of intentionally lagging Intel's releases by roughly six months, so when the kernel complains, it it for _really_ old microcode" * tag 'x86_microcode_for_7.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode/intel: Refresh old_microcode defines with the May 2026 release
13 daysMerge tag 'x86_sev_for_v7.4_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SEV updates from Borislav Petkov: - Report in sysfs which SEV confidential computing features are enabled in the environment so that related components like a SVSM can query them and do appropriate configuration - Add support for a new AMD SEV instruction called RMPOPT which can be used to reduce the performance overhead of doing confidential guests' page ownership verification and the like. Work by Ashish Kalra * tag 'x86_sev_for_v7.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sev: Report MSR_AMD64_SEV in sysfs x86/sev: Do RMP optimizations on SNP guest shutdown x86/sev: Perform RMP optimizations asynchronously x86/sev: Initialize RMPOPT configuration MSRs x86/sev: Disable CPU hotplug while SNP is active x86/cpufeatures: Add X86_FEATURE_RMPOPT feature flag
13 daysMerge tag 'x86_cpu_for_v7.4_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu feature updates from Borislav Petkov: - Rework early CPU features detection code to handle a case where recorded CPU capabilities are temporarily cleared in an interruptible region. The practical implication of this lead to, for example, KASAN complaining due to 5-level pagetable support disappearing intermittently (Ihor Solodrai) - AMD Zen5 started reporting TLB sizes as multiples of 32 so adjust the TLB sizes reporting code to consider that - Return the proper retval when trying to enable user shadow stacks * tag 'x86_cpu_for_v7.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Don't transiently clear the boot CPU's capabilities x86/cpu: Move 32-bit SEP setup into identify_cpu() x86/cpu: Inline generic_identify() into identify_cpu() x86/cpu: Initialize boot CPU cpuinfo defaults early x86/cpu: Factor init_cpu_info() out of identify_cpu() x86/CPU/AMD: Fix Zen5 TLB sizes reporting x86/shstk: Return the correct error value when user shadow stacks are disabled
13 daysMerge tag 'x86_cleanups_for_v7.4_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Borislav Petkov: - The usual pile of cleanups all over the place * tag 'x86_cleanups_for_v7.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/asm: Remove CR4 read fault handler x86/um: Remove unused <asm/required-features.h> header x86/cpu: Constify struct x86_cpu_id x86/asm/string_64: Remove unused linux/jump_label.h include x86/mtrr: Fix kernel-doc notation of amd_set_mtrr()
13 daysMerge tag 'x86_cache_for_v7.4_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Borislav Petkov: - Push down into arch code the rounding of bandwidth control user values due to the different ways ARM and x86 report MBA - Fix task reporting for the default group for systems which support only bandwidth monitoring, aka Haswell vintage computing - The usual fixlets and improvements * tag 'x86_cache_for_v7.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: fs/resctrl: Ensure default group reports tasks on monitor-only systems x86,fs/resctrl: Add event group descriptions for Intel Diamond Rapids x86/resctrl: Update documented unit for the "activity" event fs/resctrl: Simplify pseudo_lock_measure_trigger() fs/resctrl: Avoid extra call to strlen() in schemata_list_add() fs/resctrl: Factor MBA parse-time conversion to be per-arch arm_mpam: resctrl: Add pass-through resctrl_arch_preconvert_bw() x86,fs/resctrl: Add resctrl_arch_preconvert_bw()
13 daysMerge tag 'x86_bugs_for_v7.4_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 CPU speculation updates from Borislav Petkov: - AMD Zen6's BTB has per-context tagging so there's no need for the expensive SRSO SafeRET mitigation anymore; add glue to detect and handle that - Fix Spectre v2 mitigation reporting for RETPOLINE=n builds * tag 'x86_bugs_for_v7.4_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bugs: Fix CONFIG_MITIGATION_RETPOLINE=n mitigation reporting x86/bugs: Adapt SRSO mitigation to Zen6
2026-10-16Merge tag 'kvm-x86-misc-7.4' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM x86 misc changes for 7.4 - Mask off the address space ID when checking for illegal usage of kvm_set_internal_memslot() to prevent false negatives on the sanity check. - Explicitly zero reserved flags when delivering a SynIC message to avoid leaking a byte of stack information to the guest. - Rework TDX's handling of the canonical MMU root level to not rely on userspace to fill CPUID correctly, as doing so lets userspace trivially trigger a KVM_BUG_ON(). - Reject KVM_SET_NESTED_STATE if userspace "restores" L1 with EFER.LMA=1 && EFER.LME=0, which confuses KVM into trying to configure an 64-bit MMU without PAE. - Ignore EFER.LMA (clear it from KVM's cached save state) if EFER.LME=0 when preparing L2 state, to fix another way to confuse KVM's MMU (and because real hardware also ignores EFER.LMA). - Improve KVM's sanity checks for a misconfigured MMU to (hopefully) detect all of the ways KVM can botch EFER.LMA vs. CR4.PAE. - Remove the "full" out-param from kvm_x86_ops.flush_tlb_gva() as the param is only used to avoid what effectively amounts to a single memory write. - Fix a mostly-benign bug where KVM can write through a guest's read-only mapping due to not checking the error code when expediting emulated MMIO page faults. - Honor the guest's view of the "EFER.LMSLE must be zero" defeature so that userspace can provide migration compatibility between Rome and Milan+. - Pend a KVM_REQ_EVENT request when an exception is morphed into a nested VM-Exit, otherwise KVM can fail to actually deliver the nested VM-Exit, e.g. when injecting a page fault. - Add support for PML on SVM. - Add support for virtualizing Bus Lock Detect on SVM, and fix a number of DR6 bugs and warts along the way. - Misc fixes and cleanups.
2026-10-14lkdtm: Make UNSET_SMEP built-in-only and unexport native_write_cr4()Dennis Chen
native_write_cr4 should not be exported to modules. Commit 21953ee5013d ("x86/cpu: Export native_write_cr4() only when CONFIG_LKTDM=m") restricted the export somewhat, but native_write_cr4() is still exposed to all GPL-compatible modules when CONFIG_LKDTM=m. UNSET_SMEP is the only module user of native_write_cr4(). Restrict the test to CONFIG_LKDTM=y and remove the export. When LKDTM is built as a module, report XFAIL for UNSET_SMEP. Suggested-by: Christoph Hellwig <hch@infradead.org> Link: https://lore.kernel.org/all/20200420090102.GB24518@infradead.org/ Signed-off-by: Dennis Chen <dechen@redhat.com> Link: https://patch.msgid.link/20261014175859.30863-1-dechen@redhat.com Signed-off-by: Kees Cook <kees@kernel.org>
2026-10-13Merge branch 'tip/sched/urgent'Peter Zijlstra
Pickup dependencies; notably the RB-tree fix. Signed-off-by: Peter Zijlstra <peterz@infradead.org>
2026-10-05x86/CPU/AMD: Fix AMD TLBI Erratum #1718Borislav Petkov (AMD)
The processor may fail to invalidate a TLB entry while executing an INVLPGB/TLBSYNC instruction pair. Detect the erratum and apply a software workaround when a microcode fix is not present. Fixes: 82378c6c2f43 ("x86/mm: Use INVLPGB for kernel TLB flushes") Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Rik van Riel <riel@surriel.com> Acked-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Tested-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Tested-by: Rik van Riel <riel@surriel.com> Cc: stable@kernel.org Link: https://patch.msgid.link/20261002211617.1001617-1-bp@kernel.org
2026-10-02x86/bugs: Fix CONFIG_MITIGATION_RETPOLINE=n mitigation reportingKim Phillips
When the kernel lacks retpoline support, spectre_v2_select_retpoline() emits "Kernel not compiled with retpoline; no mitigation available!" before returning SPECTRE_V2_NONE to its callers. SPECTRE_V2_NONE is not the final answer, though: spectre_v2_update_mitigation() runs afterwards and can still upgrade the mitigation. On an Intel CPU affected by RETBleed, built with CONFIG_MITIGATION_IBRS_ENTRY=y and CONFIG_MITIGATION_RETPOLINE=n, and booted with spectre_v2=auto, retbleed_select_mitigation() picks RETBLEED_MITIGATION_IBRS, and spectre_v2_update_mitigation() then promotes SPECTRE_V2_NONE to SPECTRE_V2_IBRS. The boot log claims no mitigation is available immediately before reporting "Spectre V2 : Mitigation: IBRS", and sysfs reports the machine as mitigated. The message is alarming and simply wrong. Drop "no mitigation available!" because the final mitigation state is printed afterwards in spectre_v2_update_mitigation() anyway. [ bp: Drop CC:stable, massage commit message. ] Fixes: 480e803dacf8 ("x86/bugs: Restructure spectre_v2 mitigation") Suggested-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Assisted-by: LLM Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Link: https://patch.msgid.link/20260831210916.987152-1-kim.phillips@amd.com
2026-09-30x86,fs/resctrl: Add event group descriptions for Intel Diamond RapidsTony Luck
Intel Diamond Rapids exposes Application Energy Telemetry through two new PMT aggregator GUIDs: one covering the "energy" feature, and one covering the "perf" feature, both documented in the Intel-PMT XML repository at https://github.com/intel/Intel-PMT The "perf" aggregator references two events not previously enumerated by resctrl: retired instructions (INST_RETIRED), and a count of unhalted core clock cycles perceived by hardware as contributing to instruction execution (PCNT). Add definitions for both aggregators, and add the two new events to the resctrl filesystem so they can be exposed to user space. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://patch.msgid.link/20260930171554.12794-1-tony.luck@intel.com
2026-09-28x86/cpufeatures: Add Page modification loggingNikunj A Dadhania
Page modification logging(PML) is a hardware feature designed to track guest modified memory pages. PML enables the hypervisor to identify which pages in a guest's memory have been changed since the last checkpoint or during live migration. The PML feature is advertised via CPUID leaf 0x8000000A ECX[4] bit. Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Nikunj A Dadhania <nikunj@amd.com> Link: https://patch.msgid.link/20260907063906.1964557-7-nikunj@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2026-09-28x86/microcode/intel: Refresh old_microcode defines with the May 2026 releaseSohil Mehta
Update the minimum expected revisions of Intel microcode based on the microcode-20260512 (May 2026) release. Note, the three new entries are for INTEL_PANTHERLAKE_L steppings. Signed-off-by: Sohil Mehta <sohil.mehta@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://patch.msgid.link/20260928222607.3593973-1-sohil.mehta@intel.com
2026-09-28Merge tag 'v7.3-rc5' into driver-core-nextDanilo Krummrich
We need the driver-core fixes in here as well to build on top of. Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2026-09-27x86/cpu: Constify struct x86_cpu_idChristophe JAILLET
'struct x86_cpu_id' is not modified in this compilation unit. Constifying this structure moves some data to a read-only section, so increases overall security. It is only used in cpu_has_old_microcode() which is an __init function. So, using __initconst is safe and will save about 6 kB of memory at runtime. On a x86_64, with allmodconfig: text data bss dec hex filename 55725 28774 512 85011 14c13 arch/x86/kernel/cpu/common.o.before 61464 22918 512 84894 14b9e arch/x86/kernel/cpu/common.o.after [ bp: Massage commit message. ] Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/f08d3a0e7aefe3bad66251927cbd03b8cbf9df73.1786311119.git.christophe.jaillet@wanadoo.fr
2026-09-23x86/mce: Fix hardware debug register corruption on task migrationMasami Hiramatsu (Google)
In exc_machine_check_user(), local_db_save() and local_db_restore() are invoked in the outer entry stubs (DEFINE_IDTENTRY_MCE_USER, DEFINE_FREDENTRY_MCE, and DEFINE_IDTENTRY_RAW), surrounding exc_machine_check_user(). However, exc_machine_check_user() calls irqentry_exit_to_user_mode(), which handles pending thread work and may schedule() if TIF_NEED_RESCHED is set. If the task migrates to another CPU during schedule(), local_db_restore() runs on the new CPU with the dr7 state saved from the old CPU. This corrupts the new CPU's DR7 hardware debug register and leaves the old CPU's DR7 disabled. In short, local_db_save() and local_db_restore() pair must be run on the same CPU. To fix this, move local_db_save() and local_db_restore() inside exc_machine_check_user() and exc_machine_check_kernel(). In exc_machine_check_user(), DR7 is saved and restored strictly around do_machine_check() to avoid schedule() during migration. In exc_machine_check_kernel(), local_db_save() is called at the entry point to prevent early memory accesses from triggering nested #DB exceptions, and restored on all exits. Fixes: cd840e424f27 ("x86/entry, mce: Disallow #DB during #MC") Assisted-by: LLM Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@kernel.org> Link: https://patch.msgid.link/179005109564.388919.3937970081044095776.stgit@devnote2
2026-09-22umh, treewide: Explicitly include linux/umh.h where neededPetr Pavlu
The usermode helper declarations were previously provided by linux/kmod.h but commit c1f3fa2a4fde ("kmod: split off umh headers into its own file") moved them to linux/umh.h in 2017. Add explicit includes of linux/umh.h to files that use usermode helpers and remove linux/kmod.h where it is no longer needed. Acked-by: Alex Elder <elder@riscstar.com> # for greybus Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
2026-09-18x86/cpufeatures: Add X86_FEATURE_RMPOPT feature flagAshish Kalra
Add a flag indicating whether RMPOPT instruction is supported. RMPOPT is a new instruction that reduces the performance overhead of RMP checks for the hypervisor and non-SNP guests by allowing those checks to be skipped when 1-GB memory regions are known to contain no SEV-SNP guest memory. For more information on the RMPOPT instruction, see the AMD64 RMPOPT technical documentation. [ bp: Zap respective tools/ change. ] Suggested-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Ackerley Tng <ackerleytng@google.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://patch.msgid.link/39e9ee269a572c516a3f4e937bfe12d00697d5e6.1782841284.git.ashish.kalra@amd.com
2026-09-17x86/microcode/intel: Reject problematic loading on Granite Rapids systemsChang S. Bae
Microcode updates can usually jump revisions. However, there is an erratum on Granite Rapids systems. If they "jump over" revision 0x1000405, they result in an #MC. Avoid it. Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260916225939.1144524-1-chang.seok.bae@intel.com
2026-09-17x86/cpu: Don't transiently clear the boot CPU's capabilitiesIhor Solodrai
On the boot CPU, identify_cpu() runs from arch_cpu_finalize_init(), with interrupts enabled and before alternatives are patched. So cpu_feature_enabled() still evaluates against boot_cpu_data. identify_cpu() rebuilds c->x86_capability from scratch: the reset zeroes the array and the CPUID rescan fills it in again. An interrupt delivered in that window finds X86_FEATURE_LA57 clear in boot_cpu_data, so pgtable_l5_enabled() is false and KASAN checks a 5-level address against the 4-level addressability limit. The result is a bogus "wild-memory-access" report, and under kasan_multi_shot a report storm that wedges the boot. The boot CPU has already been scanned by early_identify_cpu(), with interrupts disabled, and its capabilities cannot have changed since. Reset only the CPUs which have not been scanned yet. The window is as old as identify_cpu() rebuilding the capabilities. Commit 39b9552281ab ("x86/mm: Optimize boot-time paging mode switching cost") merely let KASAN notice it by making pgtable_l5_enabled() read the feature bit. So no Fixes: tag. Closes: https://lore.kernel.org/bpf/20260610175651.647515-1-ihor.solodrai@linux.dev/ Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20260916195203.1099646-6-ihor.solodrai@linux.dev
2026-09-17x86/cpu: Move 32-bit SEP setup into identify_cpu()Ihor Solodrai
identify_boot_cpu() and identify_secondary_cpu() both call enable_sep_cpu() under CONFIG_X86_32 immediately after identify_cpu(). Do it once and drop the ifdefs while at it. No functional changes. Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: https://patch.msgid.link/20260916195203.1099646-5-ihor.solodrai@linux.dev
2026-09-17x86/cpu: Inline generic_identify() into identify_cpu()Ihor Solodrai
generic_identify() has exactly one call site: at the top of identify_cpu(). Fold it into identify_cpu() so that a single function does the job for both the boot CPU and the secondary CPUs. While at it, fix up both copies of the Cyrix comment. No functional changes. Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20260916195203.1099646-4-ihor.solodrai@linux.dev
2026-09-17x86/cpu: Initialize boot CPU cpuinfo defaults earlyIhor Solodrai
early_identify_cpu() clears the capability array, the CPUID table and extended_cpuid_level, but the architectural defaults for the rest of struct cpuinfo_x86 are set only later, in identify_cpu(). Use the same defaults from the start, so that the boot CPU does not depend on a later reset to end up with the right ones. Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20260916195203.1099646-3-ihor.solodrai@linux.dev
2026-09-17x86/cpu: Factor init_cpu_info() out of identify_cpu()Ihor Solodrai
identify_cpu() unconditionally resets the struct cpuinfo_x86 fields to their default values and clears the capability arrays with memset() before rescanning the CPU to fill it in again. However the boot CPU capabilities have already been scanned by early_identify_cpu(), with interrupts disabled. Introduce init_cpu_info() helper in preparation for letting the callers decide whether the reset is needed. No functional changes. Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20260916195203.1099646-2-ihor.solodrai@linux.dev
2026-09-16x86/mce: Use __DEVICE_ATTR() macro to initialize dev_ext_attributeThomas Weißschuh
The upcoming constification of the device_show_int() and device_show_bool() signatures requires the users to handle the transition automatically. Switch to the __DEVICE_ATTR() macro which can do this. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Link: https://patch.msgid.link/20260907-sysfs-const-attr-dev_ext_attr-v2-1-bf53afe57071@weissschuh.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-09-15x86/mtrr: Fix kernel-doc notation of amd_set_mtrr()Manuel Ebner
Add ':' to arguments in kernel-doc comment to fix: $ ./scripts/kernel-doc -none arch/x86/kernel/cpu/mtrr/amd.c Warning: arch/x86/kernel/cpu/mtrr/amd.c:63 function parameter 'reg' not described in 'amd_set_mtrr' Warning: arch/x86/kernel/cpu/mtrr/amd.c:63 function parameter 'base' not described in 'amd_set_mtrr' Warning: arch/x86/kernel/cpu/mtrr/amd.c:63 function parameter 'size' not described in 'amd_set_mtrr' Warning: arch/x86/kernel/cpu/mtrr/amd.c:63 function parameter 'type' not described in 'amd_set_mtrr' [ bp: Massage commit message. ] Signed-off-by: Manuel Ebner <manuelebnerli@mailbox.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20260915103136.171924-3-manuelebnerli@mailbox.org
2026-09-14x86/CPU/AMD: Fix Zen5 TLB sizes reportingBorislav Petkov (AMD)
Starting with Zen5, TLB sizes in CPUID_Fn80000006_E[AB]X are reported as multiples of 32. There's a CPUID bit which determines that: CPUID_Fn80000021_EAX [Extended Feature 2 EAX] (Core::X86::Cpuid::FeatureExt2Eax) ... 14: L2TlbSizeX32. Read-only. Reset: 1. Indicates that L2TLB sizes are encoded as multiples of 32. Update the places which report that information. With it, the numbers look correct now: -Last level iTLB entries: 4KB 64, 2MB 64, 4MB 32 -Last level dTLB entries: 4KB 128, 2MB 128, 4MB 64, 1GB 0 +Last level iTLB entries: 4KB 2048, 2MB 2048, 4MB 1024 +Last level dTLB entries: 4KB 4096, 2MB 4096, 4MB 2048, 1GB 0 /proc/cpuinfo -TLB size : 192 4K pages +TLB size : 6144 4K pages Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20260821022031.946311-1-bp@kernel.org
2026-09-14x86,fs/resctrl: Add resctrl_arch_preconvert_bw()Dave Martin
On MPAM systems the rounding behaviour of the MBA control would be improved if the rounding in the fs/resctrl code is removed but this is not the case for x86. To allow any rounding or conversion of the bandwidth value provided by the user to be specified by the arch code a new arch hook is required. Introduce resctrl_arch_preconvert_bw(), and add its x86 implementation. This is currently unused in resctrl but when plumbed in it will replace the call to roundup() in bw_validate(). Signed-off-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Ben Horgan <ben.horgan@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Link: https://patch.msgid.link/20260911163613.1131447-2-ben.horgan@arm.com
2026-09-08x86/MCE/AMD: Fix inverted interrupt enablement during storm handlingJasjeet Rangi
mce_amd_handle_storm() currently does the opposite of what storm handling needs: it enables thresholding interrupts when a storm is detected and disables them when the storm subsides. Flip the "on" function argument before passing it to threshold_restart_bank() as it should have been done. To clarify: "on" to mce_handle_storm() means, the storm is on now when "on" is true, and off when "on" is false. [ bp: Simplify. ] Fixes: 5c4663ed1eac ("x86/mce: Handle AMD threshold interrupt storms") Signed-off-by: Jasjeet Rangi <jrangi@purestorage.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260812221514.598842-2-jrangi@purestorage.com
2026-09-02sched: Convert paravirt_steal to new static key APIsHongyan Xia
paravirt_steal_rq_enabled and paravirt_steal_enabled use raw static_key APIs which are now deprecated. Use the new API instead. No functional change. Signed-off-by: Hongyan Xia <hongyan.xia@transsion.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Juergen Gross <jgross@suse.com> Link: https://patch.msgid.link/20260819081207.12150-1-hongyan.xia@transsion.com
2026-09-01x86/bugs: Adapt SRSO mitigation to Zen6Borislav Petkov (AMD)
Zen6 has BTB protection which isolates the different contexts (user/kernel, guest/host) from one another. This makes the SafeRET mitigation there unnecessary leaving the user/user and guest/guest attack vectors open, whose protection is handled by the Spectre v2 mitigation setting to do IBPB on a context switch. Detect that setting and report it with a new mitigation string. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20260822013231.1109255-1-bp@kernel.org
2026-08-26Merge tag 'hyperv-next-signed-20260826' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv updates from Wei Liu: - Decrypt netvsc buffer on contiguous direct-map addresses (Kameron Carr) - Drop WS2012/2012R2 & Win8/8.1 Hyper-V support (Michael Kelley) - Use more meaningful errnos for hypercall status code (Hardik Garg) - Fix lost interrupts on CPU hot-unplug for Hyper-V PCI/MSI (Naman Jain) - Reserve more MSHV vectors for Linux root partition (Wei Liu) * tag 'hyperv-next-signed-20260826' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: clocksource: hyper-v: Remove support for stimer interrupts in message mode scsi: storvsc: Remove support for storvsc protocol of old Hyper-V hosts hv_netvsc: Remove GPADL teardown special case for old Hyper-V hosts hv_sock: Remove check for old Hyper-V hosts Drivers: hv: Remove support for WS2012/2012R2 & Win8/8.1 version of Hyper-V hv_netvsc: Allocate send/receive buffers using vmbus_alloc_buffer() Drivers: hv: vmbus: Add vmbus_alloc_buffer()/vmbus_free_buffer() for CoCo VMs Drivers: hv: vmbus: add vmbus_establish_gpadl_caller_decrypted() Drivers: hv: vmbus: Skip VMBus module cleanup for non-nested root partition x86/hyperv: reserve more vectors PCI: hv: Set irq_retrigger callback for the Hyper-V PCI MSI irqchip Drivers: hv: Use meaningful errnos for hypercall status codes
2026-08-24clocksource: hyper-v: Remove support for stimer interrupts in message modeMichael Kelley
In Hyper-V versions prior to WS2016/Win10, Hyper-V synthetic timers interrupt the guest by delivering a message that is initially handled by the Linux VMBus driver. Starting with WS2016/Win10, Hyper-V can deliver stimer interrupts directly to an assigned interrupt vector without involving the VMBus driver. This is called "Direct Mode". With the overall removal of Linux support for running on Hyper-V hosts earlier than WS2016 and Windows 10, it's no longer necessary to support the legacy message-based delivery. Remove that delivery mechanism and always use Direct Mode. If for some reason, the Hyper-V host does not enumerate Direct Mode, output an error message but continue to run using the LAPIC timer instead of an stimer. With these changes, the VMBus driver no longer calls the stimer interrupt service routine. This removal has a broader benefit in unblocking the disentangling of VMBus code and stimer code, as they should be independent of each other. The final disentangling will come as a follow-on patch set. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
2026-08-24x86/hyperv: reserve more vectorsWei Liu
Microsoft Hypervisor delivers three vectors to the NT HAL running in the root partition and refuses to map a device interrupt to any of them when interrupt remapping is not available in the system. As of writing, the nested MSHV setup has no interrupt remapping capability. The three vectors are: HAL_NT_APC_VECTOR 0x1F HAL_NT_DPC_VECTOR 0x2F HAL_NT_CLOCK_IPI_VECTOR 0xD2 0x1F is below FIRST_EXTERNAL_VECTOR so the vector allocator never hands it out, but 0x2F and 0xD2 are both inside the allocatable range and are handed out once enough vectors are in use. Mapping such an interrupt then fails with HV_STATUS_INVALID_PARAMETER, and the interrupt is never delivered. Reserve all three next to the hypervisor debug vectors that are already kept out of the allocator's hands. Reviewed-by: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
2026-08-20Merge tag 'mm-stable-2026-08-18-18-39' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "mm: drop "sub" prefix from various places" (Dev Jain) page->folio conversion and a naming cleanup - "mm/kasan: remove redundant initialization for kasan_flag_write_only" (Igor Putko) KASAN cleanup work - "mm/filemap: reduce unnecessary xarray lookups" (Chi Zhiling) Small speedup in the pagecaache read code - "mm/percpu: Fix possible NOFS/NOIO reclaim recursion" (Kaitao Cheng) Improve the vmalloc code - mainly the avoidance of GFP_KERNEL allocations when the caller asked for GFP_NOFS or GFP_NOIO - "mm/kmemleak: avoid soft lockup when scanning task stacks" (Breno Leitao) Avoid a soft lockup watchdog trigger from the kmemleak scanning code in extreme situations - "mm/page_owner: misc cleanups" (Ye Liu) Cleanups to the page_owner code. For some reason lots of people have been working on the page_owner code this cycle. - "mm: convert to walk_page_range_vma() to eliminate find_vma()" (Kefeng Wang) Simplify and accelerate the page walking library function - "mm/migrate: preparatory cleanups for batch copy and offload" (Shivank Garg) Cleanups in the migration code - "mm/page_owner: add per-fd filter infrastructure for print_mode and NUMA filtering" (Zhen Ni) Per-fd filtering to page_owner in order to reduce the sometimes vast amount of output it can produce - "mm: Refactor bootmem gigantic hugepage allocation" (Muchun Song) Fixes and preparatory cleanups around bootmem HugeTLB handling, sparse initialization ordering, and related vmemmap setup - "mm/zsmalloc: reduce lock contention in zs_free()" (Wenchao Hao) Reduce lock contention in zs_free(), which dominates the unmap path under memory pressure on Android (LMK kills) and on x86 servers running zswap-heavy workloads. Up to 1.83x improvement in microbenchmarking. - "move alloc_tag.c file under mm/" (Suren Baghdasaryan) - "samples/damon: handle damon_{start,stop}() failures" (SJ Park) Fix improper handling of damon_start(), damon_stop(), and damon_call() failures across DAMON sample modules to prevent potential memory leaks, operation disruptions and use-after-free bugs - "mm/damon/sysfs: kobject_del() directories that users can create/remove" (SJ Park) Fix delayed sysfs directory removal under DEBUG_KOBJECT_RELEASE causeing creation failures due to duplicate directory names by adding missing kobject_del() calls before creating new directories - "mm: cleanup clear_not_present_full_ptes()" (David Hildenbrand) Clean up the core pte handling code - "selftests/damon: misc fixes for test bugs" (Kunwu Chan) Fix several bugs in the DAMON selftests - "selftests/damon: fix memcg_path staging handling" (Cheng Nie) Fix a bug in _damon_sysfs.py for damos_filter memcg_path setup, and add a test case for it in sysfs.py. - "selftests/damon: test kdamond refresh_ms" (Ruslan Valiyev) Selftest coverage for DAMON's refresh_ms sysfs feature by updating the test control module and verifying that scheme stats update automatically without manual intervention - "mm/damon: five misc fixups" (Akinobu Mita) Miscellaneous DAMON fixups. - "mm/damon/core: detect internal variation above max_nr_regions/2" (Jiayuan Chen) Fix DAMON's region splitting behavior when region counts exceed half the maximum budget by dynamically scaling down the split fraction as the limit approaches, preventing large regions from staying un-split, and add corresponding KUnit test coverage - "mm: preparatory patches for PMD level swap entries" (Usama Arif) Refactor and clean up PMD softleaf helpers, call sites, and architecture flags to lay the groundwork for a follow-up series that introduces PMD page table swap entries - "mm/damon: update, optimize, and clean up doc, tests, and code" (SJ Park) Update DAMON design and ABI documentation, expands unit and selftest coverage, optimize damon_commit_target_regions(), and clean up recently added sysfs interface code for better readability - "mm/vmpressure: reduce CPU, memory and code overhead on cgroup v2" (Usama Arif) Optimize vmpressure() by skipping unnecessary work on cgroup v2 for userspace event notifications and refactor v1-only eventfd handling into mm/memcontrol-v1.c to reduce memory overhead and code complexity - "selftests/mm: refactor pkey helpers and fix mmap error handling" (Hongfu Li) Refactor pkeys shared tracing and assertion helpers into a common file, unify protection key selftests to use consistent diagnostic logging and assertions, and enforce standardized MAP_FAILED return checks for mmap() calls across the tests - "mm/damon: optimize out nr_accesses_bp" (SJ Park) Replace the error-prone, continuously updated nr_accesses_bp field in damon_region with an on-demand moving sum function, reducing structure memory overhead and avoiding state corruption bugs - "Open HugeTLB allocation routine for more generic use" (Ackerley Tng) Decouple HugeTLB folio allocation from VMA dependencies by introducing hugetlb_alloc_folio(), enabling subsystems like guest_memfd to allocate HugeTLB folios without standard VMA reservations or pseudo-VMAs - "mm/damon: provide pseudo moving sum probe_hits" (SJ Park) Integrate DAMON's probe_hits attribute counter into the pseudo moving sum infrastructure, enabling real-time, online monitoring without waiting for full aggregation intervals - "mm: Some cleanups for page allocator APIs" (Brendan Jackman) Simplify and refactor the page allocator entry points and flags by unifying allocation paths, adding internal alloc_flags arguments, and eliminating redundant __ prefixed alloc_pages variants. - "Fix incorrect access of hugetlb pte entries" (Dev Jain) Enforce the consistent use of huge_ptep_get() instead of ptep_get() for HugeTLB entries and fixes an unaligned address issue in arm64's huge_ptep_get() implementation - "mm/damon: validate all parameters in the core" (SJ Park) Consolidate parameter validation into the DAMON core specifically within damon_start() and damon_commit_ctx() to centralize error checking, eliminate caller-side redundant checks and to improve maintenance efficiency - "tools/mm/page_owner_sort: fix filtering and cleanup issues" (Yichong Chen) Rename is_need() to filter_record() for clearer return semantics, fix per-record allocation memory leaks and bound output copies in search_pattern() to address an existing buffer issue - "memcg: bail out reclaim when memcg is dying" (Jiayuan Chen) Mitigate a system-wide stall which occurs when a cgroup is removed while one of its memory control files is doing synchronous reclaim - "mm/memory-failure: add panic option for unrecoverable pages" (Breno Leitao) Introduce an opt-in vm.panic_on_unrecoverable_memory_failure sysctl that immediately panics the kernel on unrecoverable memory errors in kernel-owned pages to preserve error context and prevent delayed, silent data corruption - "mm/damon: refactor damon_{start,stop,commit}() for simple error handling" (SJ Park) Refactor the DAMON core API functions to guarantee that all contexts are fully stopped when damon_start(), damon_stop(), or damon_commit() fail, eliminating the need for complex and error-prone caller-side cleanup code - "Keep tail page private zero at free and folio split" (Zi Yan) Add checks to ensure tail_page->private is zero when freeing compound or high-order pages and when promoting tail pages during large folio splits. By validating these fields at free and split time, it allows the removal of redundant private field clearing inside prep_compound_tail() - "mm: drop redundant lru_add_drain in anon folio reuse paths" (Barry Song) Eliminate redundant lru_add_drain() calls in wp_can_reuse_anon_folio() and do_swap_page() to reduce LRU lock contention and system overhead By validating folio refcounts against the LRU cache before draining and removing unnecessary drains in the swap path, it achieves up to a 30.5% reduction in drain calls during heavy swap workloads - "mm: clean up folio LRU and swap declarations" (Jianyue Wu) Reorganize folio LRU and swap code by relocating page-cluster state to mm/swap_state.c, renaming mm/swap.c to mm/folio.c, and moving MM-internal reclaim declarations into mm/internal.h. - "userfaultfd: working set tracking for VM guest memory" (Kiryl Shutsemau) Add userfaultfd support for tracking the working set of VM guest memory, so a VMM can identify hot pages and reclaim cold ones to tiered or remote storage - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 2)" (David Hildenbrand) Remove the remaining pieces of CONFIG_HAVE_BOOTMEM_INFO_NODE, performing some smaller cleanups around freeing of reserved vmemmap pages on the way. - "mm/damon: update probe hits for runtime parameter commits" (SJ Park) Ensure that DAMON's probe_hits attribute counter is properly updated when monitoring intervals are changed at runtime, matching the behavior of nr_accesses. To achieve this, it refactors and renames existing helper functions for shared use, applies the updates to probe_hits, and handles edge cases in damon_probe_hits_mvsum() to maintain measurement accuracy. - "KSM: performance optimizations for rmap_walk_ksm" (xu xin) Resolve a severe KSM reverse-mapping performance bottleneck where thousands of split VMAs sharing a single anon_vma cause extended lock contention. By adding an interval-filtering check during the rmap walk, it reduces worst-case anon_vma lock hold times from over 500ms down to under 2ms, preventing application freezes and latency spikes under memory pressure. - "mm: split a couple of headers from internal.h" (Mike Rapoport) Split declarations related to mm_init, memblock, vmalloc and sparse into new headers - "KSM: use linear_page_index in collect_procs_ksm()" (xu xin) Apply the interval tree optimization from rmap_walk_ksm() to collect_procs_ksm() to avoid iterating over non-matching VMAs during KSM memory error handling. It hoists loop-invariant address initialization and restricts the anon_vma_interval_tree_foreach walk to a targeted page offset range, reducing redundant checks and improving lookup efficiency. - "selftests/mm: avoid false failures in hugetlb and KSM tests" (Sayali Patil) Fix issues in the hugetlb and KSM MM selftest categories that can report failures when the prerequisites for the tests are not satisfied - "mm/damon: introduce data attributes only monitoring" (SJ Park) Introduce attribute-weighted region management in DAMON, allowing users to prioritize specific data attributes (such as page sizes or cgroups) over or instead of access monitoring. By assigning weights to attribute probes, DAMON can completely disable access tracking and adjust monitoring regions based on weighted probe-hit counters to optimize monitoring quality for attribute-focused workloads. - "mm/hmm: Add mmap lock-drop support for userfaultfd-backed mappings" (Stanislav Kinsburskii) Extend hmm_range_fault() to support userfaultfd-backed regions by allowing the mmap lock to be dropped during fault handling via a new hmm_range_fault_locked() helper. By accepting a locked pointer and signaling retry status when lock release occurs, it enables page fault resolution in userfaultfd regions while preserving backward compatibility for existing callers. - "mm: make VMA page offset handling more consistent" (Lorenzo Stoakes) Clean up and standardize how vma->vm_pgoff is accessed and manipulated across file-backed and anonymous mappings in the kernel It introduces dedicated helper functions such as vma_start_pgoff(), vma_end_pgoff(), vma_set_pgoff() and linear_page_delta() while renaming rmap interval tree helpers to better reflect their functionality. These changes establish a cleaner foundation for future work that will unify virtual page offset indexing for all anonymous and CoW'd folios. - "mm: handle device-private PMDs in walk callbacks" (Usama Arif) Address kernel panics and state corruption caused by MM walk callbacks reaching non-present device-private PMD swap entries created during HMM migrations It ensures that functions which acquire pmd_trans_huge_lock() properly recognize device-private PMDs instead of assuming a present THP or a standard migration entry. - "mm/rmap: Refactor try_to_unmap_one" (Dev Jain) Refactor try_to_unmap_one by modularizing Hugetlb, anonymous-lazyfree, and anonymous-swapbacked logic into dedicated functions, laying the structural groundwork for batched anonymous large folio unmapping. - "Docs/ABI/damon: sysfs ABI document fixes and additions" (Song Hu) Fix typos and fills in missing entries in the DAMON sysfs ABI document - "dax/kmem: atomic whole-device hotplug via sysfs" (Gregory Price) Introduce an atomic sysfs state attribute and supporting DAX/MM infrastructure to prevent userland races when offlining and removing entire memory regions By adding an unplugged state alongside standard online modes, it enables whole-device atomic hotplug control while preserving backward compatibility. - "mm: convert more vm_flags_t users to vma_flags_t" (Lorenzo Stoakes) Continue transitioning the kernel from the deprecated vm_flags_t type to vma_flags_t across core memory management infrastructure. It replaces legacy type usage in core functions such as do_mmap(), unmapped area allocation, mm->def_vma_flags, and VMA operations like mlock, mprotect, and mremap. - "Two small patches to clean up mm/mm_slot.h" (xu xin) Refactor mm_slot.h by introducing mm_slot_remove() to unify duplicate slot deletion sequences in khugepaged and KSM. It also adds code documentation explaining why mm_slot_lookup and mm_slot_insert must remain as preprocessor macros rather than static inline functions. - "mm/damon/core: hide core-private struct fields" (SJ Park) Clean up DAMON core structures by consistently marking internal-only fields with private: comment tags to prevent improper direct access from outer layers. It enforces encapsulation across core structures including damon_region, damon_target, and damon_ctx and updates DAMON_SYSFS to interact through approved access APIs instead of exposing raw struct members. - "mm/damon: unurgent fixes for infinite loop, NULL de-ref and races" (SJ Park) Address potential infinite loops, NULL dereferences, and race conditions identified in DAMON It fixes an infinite loop triggered by extreme user configurations, a NULL pointer dereference within unit tests and minor monitoring accuracy degradation caused by subtle runtime races. - "mm/page_alloc: fixes for free_pages_nolock() on RT/UP" (Brendan Jackman) Fix an NMI safety flaw in __free_frozen_pages() where freeing pages on non-SMP or PREEMPT_RT kernels can bypass can_spin_trylock() checks via non-PCP or isolated migration paths. It also resolves potential kernel crashes and privilege escalation risks triggered when BPF tracing runs in NMI context alongside memory hotplug or large allocation frees. - "mm/page_alloc: couple of followups for recent cleanups" (Brendan Jackman) Clean up and update page allocator nomenclature, documentation, and debug assertions. It aligns internal FPI_ flags with the public "nolock" naming convention, removes outdated internal implementation details from high-level page allocator comments, and eliminates obsolete VM_BUG_ON() assertions in allocation paths. - "mm/mseal: further cleanups" (Lorenzo Stoakes) Refactor and simplify the mseal implementation by clarifying API boundaries and removing unnecessary code complexity. It replaces generic do_mseal() usage outside the syscall with a dedicated mseal_mmap_page_zero() helper for MMAP_PAGE_ZERO, eliminates mm_struct parameters to enforce that sealing applies only to current->mm, and streamlines overall logic and comments with no functional changes intended. - "mm/vmscan: fix swappiness=max and clean up per-node proactive reclaim" (Ridong Chen) Resolve reclaim behavior bugs and clean up function parameters across memory reclaim paths It fixes swappiness=max in both standard reclaim and MGLRU so unswappable anonymous memory no longer falls back to evicting page cache, ensures reclaim_store() returns accurate error codes instead of collapsing all failures into -EAGAIN, and removes the obsolete gfp_mask parameter from __node_reclaim(). - "mm: mincore: misc cleanups" (Kefeng Wang) Clean up and simplifies the mincore code. Most importantly, it removes the historical special behavior that always reports VM_PFNMAP pages as non-resident. - "mm/huge_memory: drop dead split helper variants" (Kiryl Shutsemau) Two trivial cleanups in the folio split API - "mm/damon: fix uninitialized DAMOS field and kunit exec expectation bugs" (SJ Park) Resolve minor operational and testing bugs in DAMON identified by Sashiko. It initializes the damos->last_applied field to prevent occasional efficiency degradation and fixes invalid memory accesses in DAMON KUnit tests during test failure handling. - "cleanup for stable_page_flags()" (Jinjiang Tu) Clean up and refactor stable_page_flags() used by /proc/kpageflags without altering functionality. It uses BIT_ULL() to prevent shift-overflow warnings on 64-bit flag bits, converts folio-specific flag checks to standard folio_test_*() helpers, and removes redundant CONFIG_PAGE_IDLE_FLAG handling. - "Batch unmap of uffd-wp file folios" (Dev Jain) Extend batched folio unmapping support to file folios within userfaultfd write-protect (uffd-wp) VMAs by adding batching capabilities to pte_install_uffd_wp_if_needed(). This removes special-case restrictions on uffd-wp VMAs in try_to_unmap_one(), significantly simplifying the function's control flow and complexity. - "mm/early_ioremap: clarify and clean up early_ioremap_reset()" (Sang-Heon Jeon) Clarify and clean up the architecture-specific usage of __late_set_fixmap() and __late_clear_fixmap() after early_ioremap_reset() It adds explicit documentation regarding when early_ioremap_reset() must be called and removes redundant macro definitions and reset calls in the RISC-V and ARM64 architectures. - "mm: fix reclaim storms in defrag_mode" (Johannes Weiner) Address severe performance regressions, swap storms, and spurious OOMs caused by vm.defrag_mode=1 under high memory pressure in Meta production It updates the page allocator slowpath so non-movable allocation requests actively trigger direct reclaim and direct compaction at pageblock_order scale, allowing them to claim whole pageblocks rather than spinning unproductively. - "zram: lockmap tweaks" (Sebastian Siewior) Optimize and fix lockdep tracking for zram devices by consolidating per-entry lockmaps and isolate lock classes across multiple instances This reduces memory overhead by replacing per-entry lockdep_map instances with a single map per struct zram, and assigns a dynamic lock_class_key to each instance to prevent false deadlock reports when different zram devices are backed by distinct filesystems. * tag 'mm-stable-2026-08-18-18-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (501 commits) selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check selftests/mm: unpoison pages in memory-failure teardown mm/shmem: downgrade final i_blocks check in shmem_evict_inode() to pr_warn() mm/khugepaged: replace mutex_lock/mutex_unlock usage with guard macro mm/zsmalloc: fix release order of locks in zs_page_migrate() Documentation: zram: remove sections numbering ksm: stop iterating VMAs when ksm_test_exit returns true mm: fold userfaultfd_rwp() to false without CONFIG_ARCH_HAS_PTE_PROTNONE mm/migrate: report RCU-tasks quiescent states in migrate_pages_batch() zram: use a custom key for each zram object zram: move lockmap to be per-zram instead per table selftests/mm: fix gup_longterm EINVAL error message mm: page_alloc: fix non-movable reclaim storm in defrag_mode mm: page_alloc: move capture_control to the page allocator mm: compaction: support non-movable compaction for pageblock requests mm: page_alloc: __GFP_FS lockdep annotation for direct compaction hugetlb: evaluate subpool free state while locked mm/damon: remove trailing semicolons after function definitions mm/damon/ops-common: prevent migration fallback to non-target nodes mm/damon: update outdated comment about DAMOS filter handling ...
2026-08-20Merge tag 'sysctl-7.03-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl Pull sysctl updates from Joel Granados: - Fix kernel-doc warnings by adjusting in file documentation - Consolidate do_proc_* function into do_proc_vec Consolidate three slightly different implementations of applying a converter on all elements of a vector. Fixes to this function now propagate to the three types. - Replace CONFIG_PROC_SYSCTL with CONFIG_SYSCTL (they were the same) and restrict cad_pid modifications to global root (GLOBAL_ROOT_UID) * tag 'sysctl-7.03-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl: sysctl: remove CONFIG_PROC_SYSCTL, it just mirrors CONFIG_SYSCTL sysctl: move the "cad_pid" entry from pid_table[] to kern_reboot_table[] sysctl: repair some kernel-doc comments sysctl: add Returns: kernel-doc for all functions sysctl: Update API function documentation sysctl: Rename proc_doulongvec_minmax_conv to proc_doulongvec_conv sysctl: Group proc_handler declarations and document sysctl: Replace do_proc_do{int,ulong,uint}vec with do_proc_vec sysctl: Add negp parameter to douintvec converter functions sysctl: Move default converter assignment out of do_proc_dointvec
2026-08-18Merge tag 'x86_cpu_for_v7.3_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpuid updates from Borislav Petkov: - Get rid of static_cpu_has() - one less API to care about testing CPU features - Unify the handling of CPU core types (performance, efficient, etc) by mapping the vendor-specific types to Linux ones - Continuation of the work of Ahmed Darwish to centralize CPUID leaf representation * tag 'x86_cpu_for_v7.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/CPU: Rename struct cpuid_read_output to struct cpuid_output x86/cpu/scattered: Sort it properly x86/cpu: Use parsed CPUID(0x1) x86/lib: Add CPUID(0x1) family and model calculation x86/cpu: Use parsed CPUID(0x0) x86/cpu/transmeta: Rescan CPUID(0x1) after modifying capabilities x86/topology: Add TOPO_CPU_TYPE_LOW_POWER x86/topology: Name the AMD core-type values x86/topo: Map vendor CPU types to generic Linux such types x86/bugs: Don't use cpu-type matching in cpu_vuln_blacklist x86/cpu: Hide and rename static_cpu_has()
2026-08-18Merge tag 'x86_cleanups_for_v7.3_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Borislav Petkov: - The usual pile of smallish cleanups and fixlets all over the place * tag 'x86_cleanups_for_v7.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Remove unnecessary __maybe_unused annotations x86/msr: Document the I/O-like write semantics in the msr driver x86/apic: Ensure ICR register write value is handled as 32 bits x86/boot/compressed/head_64.S: Clean up SEV-related comments Documentation/arch/x86/amd-memory-encryption.rst: Fix typo x86/platform/quark: Fix kernel-doc warnings in imr.c x86/ras: Move contents from arch/x86/ras/Kconfig into drivers/ras/Kconfig x86/cpu: Move intel_get_platform_id() to cpu/intel.c x86/mm: Fix typo in comment x86/fpu: Fix kernel-doc formatting above fpu_enable_guest_xfd_features() x86/cfi: Use symmetric SYM_START and SYM_END in __CFI_TYPE() x86/cfi: Add __init_or_module annotations for fineibt
2026-08-18Merge tag 'x86_cache_for_v7.3_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Borislav Petkov: - How refreshing: no new features but a whole pile of fixes to more or less serious issues reported by Sashiko along with miscellaneous cleanups all over the place. All except one by Reinette Chatre, the one by Tony Luck. * tag 'x86_cache_for_v7.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: fs/resctrl: Inform user space when status buffer overflowed fs/resctrl: Communicate resource group deleted error via last_cmd_status fs/resctrl: Add last_cmd_status support for writes to max_threshold_occupancy fs/resctrl: Change last_cmd_status custom during input parsing fs/resctrl: Use accurate and symmetric exit flows fs/resctrl: Pass error reading event through to user space fs/resctrl: Use accurate type for rdt_resource::rid fs/resctrl: Change pattern used to track number of entries in enum resctrl_conf_type x86/resctrl: Protect against bad shift fs/resctrl: Use correct format specifier for printing error pointers fs/resctrl: Fix UAF from worker threads when domains are removed x86/resctrl: Ensure domain fully initialized before placed on RCU list fs/resctrl: Prevent deadlock and use-after-free in info file handlers fs/resctrl: Prevent use-after-free in rdtgroup_kn_put() fs/resctrl: Fix deadlock on errors during mount fs/resctrl: Move functions to avoid forward references in subsequent fixes x86,fs/resctrl: Document safe RCU list traversal
2026-08-18Merge tag 'x86-msr-2026-08-17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 MSR updates from Ingo Molnar: - Streamline the x86 MSR handling APIs along the 64-bit variants, simplifying the interfaces. Removal of the old APIs is planned for the next cycle, to reduce churn & integration pain (Juergen Gross) * tag 'x86-msr-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) x86/mce: Work around build warning after MSR-interface switch cpufreq: Stop using 32-bit MSR interfaces x86/featctl: Stop using 32-bit MSR interfaces KVM/x86: Stop using 32-bit MSR interfaces x86/mtrr: Stop using 32-bit MSR interfaces acpi: Stop using 32-bit MSR interfaces powercap: Stop using 32-bit MSR interfaces thermal/intel: Stop using 32-bit MSR interfaces x86/olpc: Stop using 32-bit MSR interfaces x86/hyperv: Stop using 32-bit MSR interfaces hwmon: Stop using 32-bit MSR interfaces EDAC: Stop using 32-bit MSR interfaces x86/cpu: Stop using 32-bit MSR interfaces x86/apic: Stop using 32-bit MSR interfaces x86/resctrl: Stop using 32-bit MSR interfaces x86/tsc: Stop using 32-bit MSR interfaces x86/amd: Stop using 32-bit MSR interfaces x86/pci: Stop using 32-bit MSR interfaces x86/hygon: Stop using 32-bit MSR interfaces x86/mce: Stop using 32-bit MSR interfaces ...
2026-08-18Merge tag 'locking-core-2026-08-17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "Futexes: - Use runtime constants for futex_hash computation (K Prateek Nayak, Peter Zijlstra) - Optimise the size check get_futex_key() (Sebastian Andrzej Siewior) - Avoid private hash use-after-free on final put (Felix Hoffmann) - Tell kmemleak we're not leaking __futex_queues (Peter Zijlstra) Rust integration updates: - Implement refcounted interrupt disable and SpinLockIrq for Rust (Boqun Feng, Heiko Carstens, Joel Fernandes, Lyude Paul) - Rust sync: add helpers for mb, dma_mb and friends; add generic memory barriers and use LKMM atomics instead of Rust atomics in the revocable code (Gary Guo) - Add abstraction and integrate synchronize_rcu() (Philipp Stanner) Lock debugging: - Add qspinlock contended_release tracepoint (Dmitry Ilvokhin, Peter Zijlstra) - Enable the printing of held locks of remote running tasks and print task CPU (Ingo Molnar) - percpu-rwsem: Annotate intentional data race in readers_active_check() (Sun Shaojie) Misc fixes and updates by Boqun Feng, Peter Zijlstra, Fangrui Song, Naveen Kumar Chaudhary and Thomas Huth" * tag 'locking-core-2026-08-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits) rust: sync: Introduce SpinLockIrq::lock_with() and friends rust: sync: Add SpinLockIrq rust: sync: Use super::* in spinlock.rs rust: helper: Add spin_{un,}lock_irq_{enable,disable}() helpers rust: Introduce interrupt module s390/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS arm64: sched/preempt: Enable HAS_SEPARATE_PREEMPT_RESCHED_BITS preempt: Introduce HAS_SEPARATE_PREEMPT_RESCHED_BITS sched: Avoid signed comparison of preempt_count() in __cant_migrate() sched: Remove the unused preempt_offset parameter of __cant_sleep() locking: Switch to _irq_{disable,enable}() variants in cleanup guards irq: Add KUnit test for refcounted interrupt enable/disable irq,spin_lock: Add counted interrupt disabling/enabling openrisc: Include <linux/cpumask.h> in smp.h preempt: Introduce __preempt_count_{sub,add}_return() preempt: Introduce HARDIRQ_DISABLE_BITS preempt: Track NMI nesting to separate per-CPU counter futex: Tell kmemleak we're not leaking __futex_queues x86/paravirt: Trace contended_release on unlock tracing/lock: Use TRACE_EVENT_FN() for contended_release ...
2026-08-18Merge tag 'for-linus-7.3-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - Small cleanups for the Xen ACPI pad driver and the gnttab driver - Fix an issue with Xen PV device initialization seen with QubesOS tests - Fixes for the Xen balloon driver and the xenbus driver - Simplify Xen related kernel configuration * tag 'for-linus-7.3-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xenbus: Unregister reboot notifier on init failure x86/xen: Drop CONFIG_XEN_PVHVM_SMP xen: Drop CONFIG_XEN_AUTO_XLATE xen: Drop CONFIG_XEN_PVHVM x86/xen: Remove redundant config dependency on X86_LOCAL_APIC x86/xen: fix init of balloon stats again xen/xenbus: check otherend_id only after it has been initialized xen/xenbus: log more information when device state got reset Xen/gnttab: adjust two uses of sizeof() ACPI: PAD: xen: Stop setting acpi_device_name/class()