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2026-02-14Merge tag 'loongarch-7.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - Select HAVE_CMPXCHG_{LOCAL,DOUBLE} - Add 128-bit atomic cmpxchg support - Add HOTPLUG_SMT implementation - Wire up memfd_secret system call - Fix boot errors and unwind errors for KASAN - Use BPF prog pack allocator and add BPF arena support - Update dts files to add nand controllers - Some bug fixes and other small changes * tag 'loongarch-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: LoongArch: dts: loongson-2k1000: Add nand controller support LoongArch: dts: loongson-2k0500: Add nand controller support LoongArch: BPF: Implement bpf_addr_space_cast instruction LoongArch: BPF: Implement PROBE_MEM32 pseudo instructions LoongArch: BPF: Use BPF prog pack allocator LoongArch: Use IS_ERR_PCPU() macro for KGDB LoongArch: Rework KASAN initialization for PTW-enabled systems LoongArch: Disable instrumentation for setup_ptwalker() LoongArch: Remove some extern variables in source files LoongArch: Guard percpu handler under !CONFIG_PREEMPT_RT LoongArch: Handle percpu handler address for ORC unwinder LoongArch: Use %px to print unmodified unwinding address LoongArch: Prefer top-down allocation after arch_mem_init() LoongArch: Add HOTPLUG_SMT implementation LoongArch: Make cpumask_of_node() robust against NUMA_NO_NODE LoongArch: Wire up memfd_secret system call LoongArch: Replace seq_printf() with seq_puts() for simple strings LoongArch: Add 128-bit atomic cmpxchg support LoongArch: Add detection for SC.Q support LoongArch: Select HAVE_CMPXCHG_LOCAL in Kconfig
2026-02-13Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "Loongarch: - Add more CPUCFG mask bits - Improve feature detection - Add lazy load support for FPU and binary translation (LBT) register state - Fix return value for memory reads from and writes to in-kernel devices - Add support for detecting preemption from within a guest - Add KVM steal time test case to tools/selftests ARM: - Add support for FEAT_IDST, allowing ID registers that are not implemented to be reported as a normal trap rather than as an UNDEF exception - Add sanitisation of the VTCR_EL2 register, fixing a number of UXN/PXN/XN bugs in the process - Full handling of RESx bits, instead of only RES0, and resulting in SCTLR_EL2 being added to the list of sanitised registers - More pKVM fixes for features that are not supposed to be exposed to guests - Make sure that MTE being disabled on the pKVM host doesn't give it the ability to attack the hypervisor - Allow pKVM's host stage-2 mappings to use the Force Write Back version of the memory attributes by using the "pass-through' encoding - Fix trapping of ICC_DIR_EL1 on GICv5 hosts emulating GICv3 for the guest - Preliminary work for guest GICv5 support - A bunch of debugfs fixes, removing pointless custom iterators stored in guest data structures - A small set of FPSIMD cleanups - Selftest fixes addressing the incorrect alignment of page allocation - Other assorted low-impact fixes and spelling fixes RISC-V: - Fixes for issues discoverd by KVM API fuzzing in kvm_riscv_aia_imsic_has_attr(), kvm_riscv_aia_imsic_rw_attr(), and kvm_riscv_vcpu_aia_imsic_update() - Allow Zalasr, Zilsd and Zclsd extensions for Guest/VM - Transparent huge page support for hypervisor page tables - Adjust the number of available guest irq files based on MMIO register sizes found in the device tree or the ACPI tables - Add RISC-V specific paging modes to KVM selftests - Detect paging mode at runtime for selftests s390: - Performance improvement for vSIE (aka nested virtualization) - Completely new memory management. s390 was a special snowflake that enlisted help from the architecture's page table management to build hypervisor page tables, in particular enabling sharing the last level of page tables. This however was a lot of code (~3K lines) in order to support KVM, and also blocked several features. The biggest advantages is that the page size of userspace is completely independent of the page size used by the guest: userspace can mix normal pages, THPs and hugetlbfs as it sees fit, and in fact transparent hugepages were not possible before. It's also now possible to have nested guests and guests with huge pages running on the same host - Maintainership change for s390 vfio-pci - Small quality of life improvement for protected guests x86: - Add support for giving the guest full ownership of PMU hardware (contexted switched around the fastpath run loop) and allowing direct access to data MSRs and PMCs (restricted by the vPMU model). KVM still intercepts access to control registers, e.g. to enforce event filtering and to prevent the guest from profiling sensitive host state. This is more accurate, since it has no risk of contention and thus dropped events, and also has significantly less overhead. For more information, see the commit message for merge commit bf2c3138ae36 ("Merge tag 'kvm-x86-pmu-6.20' ...") - Disallow changing the virtual CPU model if L2 is active, for all the same reasons KVM disallows change the model after the first KVM_RUN - Fix a bug where KVM would incorrectly reject host accesses to PV MSRs when running with KVM_CAP_ENFORCE_PV_FEATURE_CPUID enabled, even if those were advertised as supported to userspace, - Fix a bug with protected guest state (SEV-ES/SNP and TDX) VMs, where KVM would attempt to read CR3 configuring an async #PF entry - Fail the build if EXPORT_SYMBOL_GPL or EXPORT_SYMBOL is used in KVM (for x86 only) to enforce usage of EXPORT_SYMBOL_FOR_KVM_INTERNAL. Only a few exports that are intended for external usage, and those are allowed explicitly - When checking nested events after a vCPU is unblocked, ignore -EBUSY instead of WARNing. Userspace can sometimes put the vCPU into what should be an impossible state, and spurious exit to userspace on -EBUSY does not really do anything to solve the issue - Also throw in the towel and drop the WARN on INIT/SIPI being blocked when vCPU is in Wait-For-SIPI, which also resulted in playing whack-a-mole with syzkaller stuffing architecturally impossible states into KVM - Add support for new Intel instructions that don't require anything beyond enumerating feature flags to userspace - Grab SRCU when reading PDPTRs in KVM_GET_SREGS2 - Add WARNs to guard against modifying KVM's CPU caps outside of the intended setup flow, as nested VMX in particular is sensitive to unexpected changes in KVM's golden configuration - Add a quirk to allow userspace to opt-in to actually suppress EOI broadcasts when the suppression feature is enabled by the guest (currently limited to split IRQCHIP, i.e. userspace I/O APIC). Sadly, simply fixing KVM to honor Suppress EOI Broadcasts isn't an option as some userspaces have come to rely on KVM's buggy behavior (KVM advertises Supress EOI Broadcast irrespective of whether or not userspace I/O APIC supports Directed EOIs) - Clean up KVM's handling of marking mapped vCPU pages dirty - Drop a pile of *ancient* sanity checks hidden behind in KVM's unused ASSERT() macro, most of which could be trivially triggered by the guest and/or user, and all of which were useless - Fold "struct dest_map" into its sole user, "struct rtc_status", to make it more obvious what the weird parameter is used for, and to allow fropping these RTC shenanigans if CONFIG_KVM_IOAPIC=n - Bury all of ioapic.h, i8254.h and related ioctls (including KVM_CREATE_IRQCHIP) behind CONFIG_KVM_IOAPIC=y - Add a regression test for recent APICv update fixes - Handle "hardware APIC ISR", a.k.a. SVI, updates in kvm_apic_update_apicv() to consolidate the updates, and to co-locate SVI updates with the updates for KVM's own cache of ISR information - Drop a dead function declaration - Minor cleanups x86 (Intel): - Rework KVM's handling of VMCS updates while L2 is active to temporarily switch to vmcs01 instead of deferring the update until the next nested VM-Exit. The deferred updates approach directly contributed to several bugs, was proving to be a maintenance burden due to the difficulty in auditing the correctness of deferred updates, and was polluting "struct nested_vmx" with a growing pile of booleans - Fix an SGX bug where KVM would incorrectly try to handle EPCM page faults, and instead always reflect them into the guest. Since KVM doesn't shadow EPCM entries, EPCM violations cannot be due to KVM interference and can't be resolved by KVM - Fix a bug where KVM would register its posted interrupt wakeup handler even if loading kvm-intel.ko ultimately failed - Disallow access to vmcb12 fields that aren't fully supported, mostly to avoid weirdness and complexity for FRED and other features, where KVM wants enable VMCS shadowing for fields that conditionally exist - Print out the "bad" offsets and values if kvm-intel.ko refuses to load (or refuses to online a CPU) due to a VMCS config mismatch x86 (AMD): - Drop a user-triggerable WARN on nested_svm_load_cr3() failure - Add support for virtualizing ERAPS. Note, correct virtualization of ERAPS relies on an upcoming, publicly announced change in the APM to reduce the set of conditions where hardware (i.e. KVM) *must* flush the RAP - Ignore nSVM intercepts for instructions that are not supported according to L1's virtual CPU model - Add support for expedited writes to the fast MMIO bus, a la VMX's fastpath for EPT Misconfig - Don't set GIF when clearing EFER.SVME, as GIF exists independently of SVM, and allow userspace to restore nested state with GIF=0 - Treat exit_code as an unsigned 64-bit value through all of KVM - Add support for fetching SNP certificates from userspace - Fix a bug where KVM would use vmcb02 instead of vmcb01 when emulating VMLOAD or VMSAVE on behalf of L2 - Misc fixes and cleanups x86 selftests: - Add a regression test for TPR<=>CR8 synchronization and IRQ masking - Overhaul selftest's MMU infrastructure to genericize stage-2 MMU support, and extend x86's infrastructure to support EPT and NPT (for L2 guests) - Extend several nested VMX tests to also cover nested SVM - Add a selftest for nested VMLOAD/VMSAVE - Rework the nested dirty log test, originally added as a regression test for PML where KVM logged L2 GPAs instead of L1 GPAs, to improve test coverage and to hopefully make the test easier to understand and maintain guest_memfd: - Remove kvm_gmem_populate()'s preparation tracking and half-baked hugepage handling. SEV/SNP was the only user of the tracking and it can do it via the RMP - Retroactively document and enforce (for SNP) that KVM_SEV_SNP_LAUNCH_UPDATE and KVM_TDX_INIT_MEM_REGION require the source page to be 4KiB aligned, to avoid non-trivial complexity for something that no known VMM seems to be doing and to avoid an API special case for in-place conversion, which simply can't support unaligned sources - When populating guest_memfd memory, GUP the source page in common code and pass the refcounted page to the vendor callback, instead of letting vendor code do the heavy lifting. Doing so avoids a looming deadlock bug with in-place due an AB-BA conflict betwee mmap_lock and guest_memfd's filemap invalidate lock Generic: - Fix a bug where KVM would ignore the vCPU's selected address space when creating a vCPU-specific mapping of guest memory. Actually this bug could not be hit even on x86, the only architecture with multiple address spaces, but it's a bug nevertheless" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (267 commits) KVM: s390: Increase permitted SE header size to 1 MiB MAINTAINERS: Replace backup for s390 vfio-pci KVM: s390: vsie: Fix race in acquire_gmap_shadow() KVM: s390: vsie: Fix race in walk_guest_tables() KVM: s390: Use guest address to mark guest page dirty irqchip/riscv-imsic: Adjust the number of available guest irq files RISC-V: KVM: Transparent huge page support RISC-V: KVM: selftests: Add Zalasr extensions to get-reg-list test RISC-V: KVM: Allow Zalasr extensions for Guest/VM KVM: riscv: selftests: Add riscv vm satp modes KVM: riscv: selftests: add Zilsd and Zclsd extension to get-reg-list test riscv: KVM: allow Zilsd and Zclsd extensions for Guest/VM RISC-V: KVM: Skip IMSIC update if vCPU IMSIC state is not initialized RISC-V: KVM: Fix null pointer dereference in kvm_riscv_aia_imsic_rw_attr() RISC-V: KVM: Fix null pointer dereference in kvm_riscv_aia_imsic_has_attr() RISC-V: KVM: Remove unnecessary 'ret' assignment KVM: s390: Add explicit padding to struct kvm_s390_keyop KVM: LoongArch: selftests: Add steal time test case LoongArch: KVM: Add paravirt vcpu_is_preempted() support in guest side LoongArch: KVM: Add paravirt preempt feature in hypervisor side ...
2026-02-12Merge tag 'riscv-for-linus-7.0-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Paul Walmsley: - Add support for control flow integrity for userspace processes. This is based on the standard RISC-V ISA extensions Zicfiss and Zicfilp - Improve ptrace behavior regarding vector registers, and add some selftests - Optimize our strlen() assembly - Enable the ISO-8859-1 code page as built-in, similar to ARM64, for EFI volume mounting - Clean up some code slightly, including defining copy_user_page() as copy_page() rather than memcpy(), aligning us with other architectures; and using max3() to slightly simplify an expression in riscv_iommu_init_check() * tag 'riscv-for-linus-7.0-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (42 commits) riscv: lib: optimize strlen loop efficiency selftests: riscv: vstate_exec_nolibc: Use the regular prctl() function selftests: riscv: verify ptrace accepts valid vector csr values selftests: riscv: verify ptrace rejects invalid vector csr inputs selftests: riscv: verify syscalls discard vector context selftests: riscv: verify initial vector state with ptrace selftests: riscv: test ptrace vector interface riscv: ptrace: validate input vector csr registers riscv: csr: define vtype register elements riscv: vector: init vector context with proper vlenb riscv: ptrace: return ENODATA for inactive vector extension kselftest/riscv: add kselftest for user mode CFI riscv: add documentation for shadow stack riscv: add documentation for landing pad / indirect branch tracking riscv: create a Kconfig fragment for shadow stack and landing pad support arch/riscv: add dual vdso creation logic and select vdso based on hw arch/riscv: compile vdso with landing pad and shadow stack note riscv: enable kernel access to shadow stack memory via the FWFT SBI call riscv: add kernel command line option to opt out of user CFI riscv/hwprobe: add zicfilp / zicfiss enumeration in hwprobe ...
2026-02-12Merge tag 'ata-6.20-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux Pull ATA updates from Damien Le Moal: - Cleanup IRQ masking in the handling of completed report zones commands (Niklas) - Improve the handling of Thunderbolt attached devices to speed up device removal (Henry) - Several patches to generalize the existing max_sec quirks to facilitates quirking the maximum command size of buggy drives, many of which have recently showed up with the recent increase of the default max_sectors block limit (Niklas) - Cleanup the ahci-platform and sata dt-bindings schema (Rob, Manivannan) - Improve device node scan in the ahci-dwc driver (Krzysztof) - Remove clang W=1 warnings with the ahci-imx and ahci-xgene drivers (Krzysztof) - Fix a long standing potential command starvation situation with non-NCQ commands issued when NCQ commands are on-going (me) - Limit max_sectors to 8191 on the INTEL SSDSC2KG480G8 SSD (Niklas) - Remove Vesa Local Bus (VLB) support in the pata_legacy driver (Ethan) - Simple fixes in the pata_cypress (typo) and pata_ftide010 (timing) drivers (Ethan, Linus W) * tag 'ata-6.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux: ata: pata_ftide010: Fix some DMA timings ata: pata_cypress: fix typo in error message ata: pata_legacy: remove VLB support ata: libata-core: Quirk INTEL SSDSC2KG480G8 max_sectors dt-bindings: ata: sata: Document the graph port ata: libata-scsi: avoid Non-NCQ command starvation ata: libata-scsi: refactor ata_scsi_translate() ata: ahci-xgene: Fix Wvoid-pointer-to-enum-cast warning ata: ahci-imx: Fix Wvoid-pointer-to-enum-cast warning ata: ahci-dwc: Simplify with scoped for each OF child loop dt-bindings: ata: ahci-platform: Drop unnecessary select schema ata: libata: Allow more quirks ata: libata: Add libata.force parameter max_sec ata: libata: Add support to parse equal sign in libata.force ata: libata: Change libata.force to use the generic ATA_QUIRK_MAX_SEC quirk ata: libata: Add ata_force_get_fe_for_dev() helper ata: libata: Add ATA_QUIRK_MAX_SEC and convert all device quirks ata: libata: avoid long timeouts on hot-unplugged SATA DAS ata: libata-scsi: Remove superfluous local_irq_save()
2026-02-12Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - "ocfs2: give ocfs2 the ability to reclaim suballocator free bg" saves disk space by teaching ocfs2 to reclaim suballocator block group space (Heming Zhao) - "Add ARRAY_END(), and use it to fix off-by-one bugs" adds the ARRAY_END() macro and uses it in various places (Alejandro Colomar) - "vmcoreinfo: support VMCOREINFO_BYTES larger than PAGE_SIZE" makes the vmcore code future-safe, if VMCOREINFO_BYTES ever exceeds the page size (Pnina Feder) - "kallsyms: Prevent invalid access when showing module buildid" cleans up kallsyms code related to module buildid and fixes an invalid access crash when printing backtraces (Petr Mladek) - "Address page fault in ima_restore_measurement_list()" fixes a kexec-related crash that can occur when booting the second-stage kernel on x86 (Harshit Mogalapalli) - "kho: ABI headers and Documentation updates" updates the kexec handover ABI documentation (Mike Rapoport) - "Align atomic storage" adds the __aligned attribute to atomic_t and atomic64_t definitions to get natural alignment of both types on csky, m68k, microblaze, nios2, openrisc and sh (Finn Thain) - "kho: clean up page initialization logic" simplifies the page initialization logic in kho_restore_page() (Pratyush Yadav) - "Unload linux/kernel.h" moves several things out of kernel.h and into more appropriate places (Yury Norov) - "don't abuse task_struct.group_leader" removes the usage of ->group_leader when it is "obviously unnecessary" (Oleg Nesterov) - "list private v2 & luo flb" adds some infrastructure improvements to the live update orchestrator (Pasha Tatashin) * tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (107 commits) watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency procfs: fix missing RCU protection when reading real_parent in do_task_stat() watchdog/softlockup: fix sample ring index wrap in need_counting_irqs() kcsan, compiler_types: avoid duplicate type issues in BPF Type Format kho: fix doc for kho_restore_pages() tests/liveupdate: add in-kernel liveupdate test liveupdate: luo_flb: introduce File-Lifecycle-Bound global state liveupdate: luo_file: Use private list list: add kunit test for private list primitives list: add primitives for private list manipulations delayacct: fix uapi timespec64 definition panic: add panic_force_cpu= parameter to redirect panic to a specific CPU netclassid: use thread_group_leader(p) in update_classid_task() RDMA/umem: don't abuse current->group_leader drm/pan*: don't abuse current->group_leader drm/amd: kill the outdated "Only the pthreads threading model is supported" checks drm/amdgpu: don't abuse current->group_leader android/binder: use same_thread_group(proc->tsk, current) in binder_mmap() android/binder: don't abuse current->group_leader kho: skip memoryless NUMA nodes when reserving scratch areas ...
2026-02-11Merge tag 'for-7.0/dm-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mikulas Patocka: - dm-verity: - various optimizations and fixes related to forward error correction - add a .dm-verity keyring - dm-integrity: fix bugs with growing a device in bitmap mode - dm-mpath: - fix leaking fake timeout requests - fix UAF bug caused by stale rq->bio - fix minor bugs in device creation - dm-core: - fix a bug related to blkg association - avoid unnecessary blk-crypto work on invalid keys - dm-bufio: - dm-bufio cleanup and optimization (reducing hash table lookups) - various other minor fixes and cleanups * tag 'for-7.0/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (35 commits) dm mpath: make pg_init_delay_msecs settable Revert "dm: fix a race condition in retrieve_deps" dm mpath: Add missing dm_put_device when failing to get scsi dh name dm vdo encodings: clean up header and version functions dm: use bio_clone_blkg_association dm: fix excessive blk-crypto operations for invalid keys dm-verity: fix section mismatch error dm-unstripe: fix mapping bug when there are multiple targets in a table dm-integrity: fix recalculation in bitmap mode dm-bufio: avoid redundant buffer_tree lookups dm-bufio: merge cache_put() into cache_put_and_wake() selftests: add dm-verity keyring selftests dm-verity: add dm-verity keyring dm: clear cloned request bio pointer when last clone bio completes dm-verity: fix up various workqueue-related comments dm-verity: switch to bio_advance_iter_single() dm-verity: consolidate the BH and normal work structs dm: add WQ_PERCPU to alloc_workqueue users dm-integrity: fix a typo in the code for write/discard race dm: use READ_ONCE in dm_blk_report_zones ...
2026-02-11Merge tag 'iommu-updates-v7.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux Pull iommu updates from Joerg Roedel: "Core changes: - Rust bindings for IO-pgtable code - IOMMU page allocation debugging support - Disable ATS during PCI resets Intel VT-d changes: - Skip dev-iotlb flush for inaccessible PCIe device - Flush cache for PASID table before using it - Use right invalidation method for SVA and NESTED domains - Ensure atomicity in context and PASID entry updates AMD-Vi changes: - Support for nested translations - Other minor improvements ARM-SMMU-v2 changes: - Configure SoC-specific prefetcher settings for Qualcomm's "MDSS" ARM-SMMU-v3 changes: - Improve CMDQ locking fairness for pathetically small queue sizes - Remove tracking of the IAS as this is only relevant for AArch32 and was causing C_BAD_STE errors - Add device-tree support for NVIDIA's CMDQV extension - Allow some hitless transitions for the 'MEV' and 'EATS' STE fields - Don't disable ATS for nested S1-bypass nested domains - Additions to the kunit selftests" * tag 'iommu-updates-v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux: (54 commits) iommupt: Always add IOVA range to iotlb_gather in gather_range_pages() iommu/amd: serialize sequence allocation under concurrent TLB invalidations iommu/amd: Fix type of type parameter to amd_iommufd_hw_info() iommu/arm-smmu-v3: Do not set disable_ats unless vSTE is Translate iommu/arm-smmu-v3-test: Add nested s1bypass/s1dssbypass coverage iommu/arm-smmu-v3: Mark EATS_TRANS safe when computing the update sequence iommu/arm-smmu-v3: Mark STE MEV safe when computing the update sequence iommu/arm-smmu-v3: Add update_safe bits to fix STE update sequence iommu/arm-smmu-v3: Add device-tree support for CMDQV driver iommu/tegra241-cmdqv: Decouple driver from ACPI iommu/arm-smmu-qcom: Restore ACTLR settings for MDSS on sa8775p iommu/vt-d: Fix race condition during PASID entry replacement iommu/vt-d: Clear Present bit before tearing down context entry iommu/vt-d: Clear Present bit before tearing down PASID entry iommu/vt-d: Flush piotlb for SVM and Nested domain iommu/vt-d: Flush cache for PASID table before using it iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode iommu/vt-d: Skip dev-iotlb flush for inaccessible PCIe device without scalable mode rust: iommu: fix `srctree` link warning rust: iommu: fix Rust formatting ...
2026-02-11Merge tag 'wq-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds
Pull workqueue updates from Tejun Heo: - Rework the rescuer to process work items one-by-one instead of slurping all pending work items in a single pass. As there is only one rescuer per workqueue, a single long-blocking work item could cause high latency for all tasks queued behind it, even after memory pressure is relieved and regular kworkers become available to service them. - Add CONFIG_BOOTPARAM_WQ_STALL_PANIC build-time option and workqueue.panic_on_stall_time parameter for time-based stall panic, giving systems more control over workqueue stall handling. - Replace BUG_ON() with panic() in the stall panic path for clearer intent and more informative output. * tag 'wq-for-6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: replace BUG_ON with panic in panic_on_wq_watchdog workqueue: add time-based panic for stalls workqueue: add CONFIG_BOOTPARAM_WQ_STALL_PANIC option workqueue: Process extra works in rescuer on memory pressure workqueue: Process rescuer work items one-by-one using a cursor workqueue: Make send_mayday() take a PWQ argument directly
2026-02-11Merge tag 'kvm-x86-pmu-6.20' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM mediated PMU support for 6.20 Add support for mediated PMUs, where KVM gives the guest full ownership of PMU hardware (contexted switched around the fastpath run loop) and allows direct access to data MSRs and PMCs (restricted by the vPMU model), but intercepts access to control registers, e.g. to enforce event filtering and to prevent the guest from profiling sensitive host state. To keep overall complexity reasonable, mediated PMU usage is all or nothing for a given instance of KVM (controlled via module param). The Mediated PMU is disabled default, partly to maintain backwards compatilibity for existing setup, partly because there are tradeoffs when running with a mediated PMU that may be non-starters for some use cases, e.g. the host loses the ability to profile guests with mediated PMUs, the fastpath run loop is also a blind spot, entry/exit transitions are more expensive, etc. Versus the emulated PMU, where KVM is "just another perf user", the mediated PMU delivers more accurate profiling and monitoring (no risk of contention and thus dropped events), with significantly less overhead (fewer exits and faster emulation/programming of event selectors) E.g. when running Specint-2017 on a single-socket Sapphire Rapids with 56 cores and no-SMT, and using perf from within the guest: Perf command: a. basic-sampling: perf record -F 1000 -e 6-instructions -a --overwrite b. multiplex-sampling: perf record -F 1000 -e 10-instructions -a --overwrite Guest performance overhead: --------------------------------------------------------------------------- | Test case | emulated vPMU | all passthrough | passthrough with | | | | | event filters | --------------------------------------------------------------------------- | basic-sampling | 33.62% | 4.24% | 6.21% | --------------------------------------------------------------------------- | multiplex-sampling | 79.32% | 7.34% | 10.45% | ---------------------------------------------------------------------------
2026-02-10Merge tag 'powerpc-7.0-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates for 7.0 - Implement masked user access - Add bpf support for internal only per-CPU instructions and inline the bpf_get_smp_processor_id() and bpf_get_current_task() functions - Fix pSeries MSI-X allocation failure when quota is exceeded - Fix recursive pci_lock_rescan_remove locking in EEH event handling - Support tailcalls with subprogs & BPF exceptions on 64bit - Extend "trusted" keys to support the PowerVM Key Wrapping Module (PKWM) Thanks to Abhishek Dubey, Christophe Leroy, Gaurav Batra, Guangshuo Li, Jarkko Sakkinen, Mahesh Salgaonkar, Mimi Zohar, Miquel Sabaté Solà, Nam Cao, Narayana Murty N, Nayna Jain, Nilay Shroff, Puranjay Mohan, Saket Kumar Bhaskar, Sourabh Jain, Srish Srinivasan, and Venkat Rao Bagalkote. * tag 'powerpc-7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (27 commits) powerpc/pseries: plpks: export plpks_wrapping_is_supported docs: trusted-encryped: add PKWM as a new trust source keys/trusted_keys: establish PKWM as a trusted source pseries/plpks: add HCALLs for PowerVM Key Wrapping Module pseries/plpks: expose PowerVM wrapping features via the sysfs powerpc/pseries: move the PLPKS config inside its own sysfs directory pseries/plpks: fix kernel-doc comment inconsistencies powerpc/smp: Add check for kcalloc() failure in parse_thread_groups() powerpc: kgdb: Remove OUTBUFMAX constant powerpc64/bpf: Additional NVR handling for bpf_throw powerpc64/bpf: Support exceptions powerpc64/bpf: Add arch_bpf_stack_walk() for BPF JIT powerpc64/bpf: Avoid tailcall restore from trampoline powerpc64/bpf: Support tailcalls with subprogs powerpc64/bpf: Moving tail_call_cnt to bottom of frame powerpc/eeh: fix recursive pci_lock_rescan_remove locking in EEH event handling powerpc/pseries: Fix MSI-X allocation failure when quota is exceeded powerpc/iommu: bypass DMA APIs for coherent allocations for pre-mapped memory powerpc64/bpf: Inline bpf_get_smp_processor_id() and bpf_get_current_task/_btf() powerpc64/bpf: Support internal-only MOV instruction to resolve per-CPU addrs ...
2026-02-10Merge tag 'x86_cache_for_v7.0_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Borislav Petkov: - Extend the resctrl machinery to support telemetry monitoring on Intel (Tony Luck) The practical usage of this is being able to tell how much energy or how much work can be attributed to a group of tasks tracked under a single idenitifier. Prepend this work with proper refactoring of resctrl domains handling code. * tag 'x86_cache_for_v7.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits) x86,fs/resctrl: Update documentation for telemetry events x86/resctrl: Enable RDT_RESOURCE_PERF_PKG fs/resctrl: Move RMID initialization to first mount x86,fs/resctrl: Compute number of RMIDs as minimum across resources fs/resctrl: Move allocation/free of closid_num_dirty_rmid[] x86/resctrl: Handle number of RMIDs supported by RDT_RESOURCE_PERF_PKG x86/resctrl: Add energy/perf choices to rdt boot option x86,fs/resctrl: Handle domain creation/deletion for RDT_RESOURCE_PERF_PKG fs/resctrl: Refactor rmdir_mondata_subdir_allrdtgrp() fs/resctrl: Refactor mkdir_mondata_subdir() x86/resctrl: Read telemetry events x86/resctrl: Find and enable usable telemetry events x86,fs/resctrl: Add architectural event pointer x86,fs/resctrl: Fill in details of events for performance and energy GUIDs x86/resctrl: Discover hardware telemetry events fs/resctrl: Emphasize that L3 monitoring resource is required for summing domains x86,fs/resctrl: Add and initialize a resource for package scope monitoring x86,fs/resctrl: Add an architectural hook called for first mount x86,fs/resctrl: Support binary fixed point event counters x86,fs/resctrl: Handle events that can be read from any CPU ...
2026-02-10Merge tag 'x86-boot-2026-02-09' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/boot updates from Ingo Molnar: - x86/acpi: Add acpi=spcr to use SPCR-provided default console (Shenghao Yang) - x86/acpi/boot: Correct the acpi_is_processor_usable() check again (Yazen Ghannam) - Refresh the x86 memory map (e820 table) handling code, and make the printouts a bit more informative (Ingo Molnar) * tag 'x86-boot-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits) x86/acpi: Add acpi=spcr to use SPCR-provided default console x86/boot/e820: Use <linux/sizes.h> symbols for literals x86/boot/e820: Make sure e820_search_gap() finds all gaps x86/boot/e820: Simplify the e820__range_remove() API x86/boot/e820: Remove e820__range_remove()'s unused return parameter x86/boot/e820: Simplify append_e820_table() and remove restriction on single-entry tables x86/boot/e820: Standardize __init/__initdata tag placement x86/boot/e820: Simplify & clarify __e820__range_add() a bit x86/boot/e820: Rename gap_start/gap_size to max_gap_start/max_gap_start in e820_search_gap() et al x86/boot/e820: Change e820_search_gap() to search for the highest-address PCI gap x86/boot/e820: Clean up e820__setup_pci_gap()/e820_search_gap() a bit x86/boot/e820: Change struct e820_table::nr_entries type from __u32 to u32 x86/boot/e820: Standardize e820 table index variable types under 'u32' x86/boot/e820: Standardize e820 table index variable names under 'idx' x86/boot/e820: Remove unnecessary header inclusions x86/boot/e820: Clean up __refdata use a bit x86/boot/e820: Clean up __e820__range_add() a bit x86/boot/e820: Improve e820_print_type() messages x86/boot/e820: Clean up confusing and self-contradictory verbiage around E820 related resource allocations x86/boot/e820: Remove pointless early_panic() indirection ...
2026-02-10Merge tag 'sched-core-2026-02-09' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Scheduler Kconfig space updates: - Further consolidate configurable preemption modes (Peter Zijlstra) Reduce the number of architectures that are allowed to offer PREEMPT_NONE and PREEMPT_VOLUNTARY, reducing the number of preemption models from four to just two: 'full' and 'lazy' on up-to-date architectures (arm64, loongarch, powerpc, riscv, s390, x86). None and voluntary are only available as legacy features on platforms that don't implement lazy preemption yet, or which don't even support preemption. The goal is to eventually remove cond_resched() and voluntary preemption altogether. RSEQ based 'scheduler time slice extension' support (Thomas Gleixner and Peter Zijlstra): This allows a thread to request a time slice extension when it enters a critical section to avoid contention on a resource when the thread is scheduled out inside of the critical section. - Add fields and constants for time slice extension - Provide static branch for time slice extensions - Add statistics for time slice extensions - Add prctl() to enable time slice extensions - Implement sys_rseq_slice_yield() - Implement syscall entry work for time slice extensions - Implement time slice extension enforcement timer - Reset slice extension when scheduled - Implement rseq_grant_slice_extension() - entry: Hook up rseq time slice extension - selftests: Implement time slice extension test - Allow registering RSEQ with slice extension - Move slice_ext_nsec to debugfs - Lower default slice extension - selftests/rseq: Add rseq slice histogram script Scheduler performance/scalability improvements: - Update rq->avg_idle when a task is moved to an idle CPU, which improves the scalability of various workloads (Shubhang Kaushik) - Reorder fields in 'struct rq' for better caching (Blake Jones) - Fair scheduler SMP NOHZ balancing code speedups (Shrikanth Hegde): - Move checking for nohz cpus after time check - Change likelyhood of nohz.nr_cpus - Remove nohz.nr_cpus and use weight of cpumask instead - Avoid false sharing for sched_clock_irqtime (Wangyang Guo) - Cleanups (Yury Norov): - Drop useless cpumask_empty() in find_energy_efficient_cpu() - Simplify task_numa_find_cpu() - Use cpumask_weight_and() in sched_balance_find_dst_group() DL scheduler updates: - Add a deadline server for sched_ext tasks (by Andrea Righi and Joel Fernandes, with fixes by Peter Zijlstra) RT scheduler updates: - Skip currently executing CPU in rto_next_cpu() (Chen Jinghuang) Entry code updates and performance improvements (Jinjie Ruan) This is part of the scheduler tree in this cycle due to inter- dependencies with the RSEQ based time slice extension work: - Remove unused syscall argument from syscall_trace_enter() - Rework syscall_exit_to_user_mode_work() for architecture reuse - Add arch_ptrace_report_syscall_entry/exit() - Inline syscall_exit_work() and syscall_trace_enter() Scheduler core updates (Peter Zijlstra): - Rework sched_class::wakeup_preempt() and rq_modified_*() - Avoid rq->lock bouncing in sched_balance_newidle() - Rename rcu_dereference_check_sched_domain() => rcu_dereference_sched_domain() - <linux/compiler_types.h>: Add the __signed_scalar_typeof() helper Fair scheduler updates/refactoring (Peter Zijlstra and Ingo Molnar): - Fold the sched_avg update - Change rcu_dereference_check_sched_domain() to rcu-sched - Switch to rcu_dereference_all() - Remove superfluous rcu_read_lock() - Limit hrtick work - Join two #ifdef CONFIG_FAIR_GROUP_SCHED blocks - Clean up comments in 'struct cfs_rq' - Separate se->vlag from se->vprot - Rename cfs_rq::avg_load to cfs_rq::sum_weight - Rename cfs_rq::avg_vruntime to ::sum_w_vruntime & helper functions - Introduce and use the vruntime_cmp() and vruntime_op() wrappers for wrapped-signed aritmetics - Sort out 'blocked_load*' namespace noise Scheduler debugging code updates: - Export hidden tracepoints to modules (Gabriele Monaco) - Convert copy_from_user() + kstrtouint() to kstrtouint_from_user() (Fushuai Wang) - Add assertions to QUEUE_CLASS (Peter Zijlstra) - hrtimer: Fix tracing oddity (Thomas Gleixner) Misc fixes and cleanups: - Re-evaluate scheduling when migrating queued tasks out of throttled cgroups (Zicheng Qu) - Remove task_struct->faults_disabled_mapping (Christoph Hellwig) - Fix math notation errors in avg_vruntime comment (Zhan Xusheng) - sched/cpufreq: Use %pe format for PTR_ERR() printing (zenghongling)" * tag 'sched-core-2026-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits) sched: Re-evaluate scheduling when migrating queued tasks out of throttled cgroups sched/cpufreq: Use %pe format for PTR_ERR() printing sched/rt: Skip currently executing CPU in rto_next_cpu() sched/clock: Avoid false sharing for sched_clock_irqtime selftests/sched_ext: Add test for DL server total_bw consistency selftests/sched_ext: Add test for sched_ext dl_server sched/debug: Fix dl_server (re)start conditions sched/debug: Add support to change sched_ext server params sched_ext: Add a DL server for sched_ext tasks sched/debug: Stop and start server based on if it was active sched/debug: Fix updating of ppos on server write ops sched/deadline: Clear the defer params entry: Inline syscall_exit_work() and syscall_trace_enter() entry: Add arch_ptrace_report_syscall_entry/exit() entry: Rework syscall_exit_to_user_mode_work() for architecture reuse entry: Remove unused syscall argument from syscall_trace_enter() sched: remove task_struct->faults_disabled_mapping sched: Update rq->avg_idle when a task is moved to an idle CPU selftests/rseq: Add rseq slice histogram script hrtimer: Fix trace oddity ...
2026-02-10LoongArch: Add HOTPLUG_SMT implementationHuacai Chen
For benchmarking or debugging purpose, we usually want to control SMT via boot parameter and sysfs knobs. So add HOTPLUG_SMT implementation. 1. Boot parameters: nosmt: Disable SMT, can be enabled via sysfs knobs. nosmt=force: Disable SMT, cannot be enabled via sysfs knobs. 2. Runtime sysfs controls: Write "on", "off", "forceoff" or the number of SMT threads (1, 2, ...) to /sys/devices/system/cpu/smt/control. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2026-02-09Merge tag 'docs-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "A slightly calmer cycle for docs this time around, though there is still a fair amount going on, including: - Some signs of life on the long-moribund Japanese translation - Documentation on policies around the use of generative tools for patch submissions, and a separate document intended for consumption by generative tools - The completion of the move of the documentation tools to tools/docs. For now we're leaving a /scripts/kernel-doc symlink behind to avoid breaking scripts - Ongoing build-system work includes the incorporation of documentation in Python code, better support for documenting variables, and lots of improvements and fixes - Automatic linking of man-page references -- cat(1), for example -- to the online pages in the HTML build ...and the usual array of typo fixes and such" * tag 'docs-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (107 commits) doc: development-process: add notice on testing tools: sphinx-build-wrapper: improve its help message docs: sphinx-build-wrapper: allow -v override -q docs: kdoc: Fix pdfdocs build for tools docs: ja_JP: process: translate 'Obtain a current source tree' docs: fix 're-use' -> 'reuse' in documentation docs: ioctl-number: fix a typo in ioctl-number.rst docs: filesystems: ensure proc pid substitutable is complete docs: automarkup.py: Skip common English words as C identifiers Documentation: use a source-read extension for the index link boilerplate docs: parse_features: make documentation more consistent docs: add parse_features module documentation docs: jobserver: do some documentation improvements docs: add jobserver module documentation docs: kabi: helpers: add documentation for each "enum" value docs: kabi: helpers: add helper for debug bits 7 and 8 docs: kabi: system_symbols: end docstring phrases with a dot docs: python: abi_regex: do some improvements at documentation docs: python: abi_parser: do some improvements at documentation docs: add kabi modules documentation ...
2026-02-09Merge tag 'for-linus-7.0-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: - fix running as Xen PVH guest in 32-bit mode without PAE - fix PV device handling for suspend/resume when running as a Xen guest - clean up workqueue usage - fix the Xen balloon driver for PVH dom0 - introduce the possibility to use hypercalls for console messages in unprivileged guests - enable Xen dom0 use of virtio devices in nested virtualization setups - simplify the xen-mcelog driver * tag 'for-linus-7.0-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xenbus: Rename helpers to freeze/thaw/restore xenbus: Use .freeze/.thaw to handle xenbus devices xen/mcelog: simplify MCE_GETCLEAR_FLAGS using xchg() xen/balloon: improve accuracy of initial balloon target for dom0 Partial revert "x86/xen: fix balloon target initialization for PVH dom0" xen: introduce xen_console_io option xen/virtio: Don't use grant-dma-ops when running as Dom0 x86/xen/pvh: Enable PAE mode for 32-bit guest only when CONFIG_X86_PAE is set xen: privcmd: WQ_PERCPU added to alloc_workqueue users xen/events: replace use of system_wq with system_percpu_wq
2026-02-09Merge tag 'vfs-7.0-rc1.initrd' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs initrd removal from Christian Brauner: "Remove the deprecated linuxrc-based initrd code path and related dead code. The linuxrc initrd path was deprecated in 2020 and this series completes its removal. If we see real-life regressions we'll revert. The core change removes handle_initrd() and init_linuxrc() — the entire flow that ran /linuxrc from an initrd, pivoted roots, and handed off to the real root filesystem. With that gone, initrd_load() becomes void (no longer short-circuits prepare_namespace()), rd_load_image() is simplified to always load /initrd.image instead of taking a path, and rd_load_disk() is deleted. The /proc/sys/kernel/real-root-dev sysctl and its backing variable are removed since they only existed for linuxrc to communicate the real root device back to the kernel. The no-op load_ramdisk= and prompt_ramdisk= parameters are dropped, and noinitrd and ramdisk_start= gain deprecation warnings. Initramfs is entirely unaffected. The non-linuxrc initrd path (root=/dev/ram0) is preserved but now carries a deprecation warning targeting January 2027 removal" * tag 'vfs-7.0-rc1.initrd' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: init: remove /proc/sys/kernel/real-root-dev initrd: remove deprecated code path (linuxrc) init: remove deprecated "load_ramdisk" and "prompt_ramdisk" command line parameters
2026-02-09Merge tag 'rcu.release.v7.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux Pull RCU updates from Boqun Feng: - RCU Tasks Trace: Re-implement RCU tasks trace in term of SRCU-fast, not only more than 500 lines of code are saved because of the reimplementation, a new set of API, rcu_read_{,un}lock_tasks_trace(), becomes possible as well. Compared to the previous rcu_read_{,un}lock_trace(), the new API avoid the task_struct accesses thanks to the SRCU-fast semantics. As a result, the old rcu_read{,un}lock_trace() API is now deprecated. - RCU Torture Test: - Multiple improvements on kvm-series.sh (parallel run and progress showing metrics) - Add context checks to rcu_torture_timer() - Make config2csv.sh properly handle comments in .boot files - Include commit discription in testid.txt - Miscellaneous RCU changes: - Reduce synchronize_rcu() latency by reporting GP kthread's CPU QS early - Use suitable gfp_flags for the init_srcu_struct_nodes() - Fix rcu_read_unlock() deadloop due to softirq - Correctly compute probability to invoke ->exp_current() in rcutorture - Make expedited RCU CPU stall warnings detect stall-end races - RCU nocb: - Remove unnecessary WakeOvfIsDeferred wake path and callback overload handling - Extract nocb_defer_wakeup_cancel() helper * tag 'rcu.release.v7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (25 commits) rcu/nocb: Extract nocb_defer_wakeup_cancel() helper rcu/nocb: Remove dead callback overload handling rcu/nocb: Remove unnecessary WakeOvfIsDeferred wake path rcu: Reduce synchronize_rcu() latency by reporting GP kthread's CPU QS early srcu: Use suitable gfp_flags for the init_srcu_struct_nodes() rcu: Fix rcu_read_unlock() deadloop due to softirq rcutorture: Correctly compute probability to invoke ->exp_current() rcu: Make expedited RCU CPU stall warnings detect stall-end races rcutorture: Add --kill-previous option to terminate previous kvm.sh runs rcutorture: Prevent concurrent kvm.sh runs on same source tree torture: Include commit discription in testid.txt torture: Make config2csv.sh properly handle comments in .boot files torture: Make kvm-series.sh give run numbers and totals torture: Make kvm-series.sh give build numbers and totals torture: Parallelize kvm-series.sh guest-OS execution rcutorture: Add context checks to rcu_torture_timer() rcutorture: Test rcu_tasks_trace_expedite_current() srcu: Create an rcu_tasks_trace_expedite_current() function checkpatch: Deprecate rcu_read_{,un}lock_trace() rcu: Update Requirements.rst for RCU Tasks Trace ...
2026-02-07workqueue: add time-based panic for stallsBreno Leitao
Add a new module parameter 'panic_on_stall_time' that triggers a panic when a workqueue stall persists for longer than the specified duration in seconds. Unlike 'panic_on_stall' which counts accumulated stall events, this parameter triggers based on the duration of a single continuous stall. This is useful for catching truly stuck workqueues rather than accumulating transient stalls. Usage: workqueue.panic_on_stall_time=120 This would panic if any workqueue pool has been stalled for 120 seconds or more. The stall duration is measured from the workqueue last progress (poll_ts) which accounts for legitimate system stalls. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-02-06Merge branches 'fixes', 'arm/smmu/updates', 'intel/vt-d', 'amd/amd-vi' and ↵Joerg Roedel
'core' into next
2026-02-03workqueue: add CONFIG_BOOTPARAM_WQ_STALL_PANIC optionBreno Leitao
Add a kernel config option to set the default value of workqueue.panic_on_stall, similar to CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC, CONFIG_BOOTPARAM_HARDLOCKUP_PANIC and CONFIG_BOOTPARAM_HUNG_TASK_PANIC. This allows setting the number of workqueue stalls before triggering a kernel panic at build time, which is useful for high-availability systems that need consistent panic-on-stall, in other words, those servers which run with CONFIG_BOOTPARAM_*_PANIC=y already. The default remains 0 (disabled). Setting it to 1 will panic on the first stall, and higher values will panic after that many stall warnings. The value can still be overridden at runtime via the workqueue.panic_on_stall boot parameter or sysfs. Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-02-03panic: add panic_force_cpu= parameter to redirect panic to a specific CPUPnina Feder
Some platforms require panic handling to execute on a specific CPU for crash dump to work reliably. This can be due to firmware limitations, interrupt routing constraints, or platform-specific requirements where only a single CPU is able to safely enter the crash kernel. Add the panic_force_cpu= kernel command-line parameter to redirect panic execution to a designated CPU. When the parameter is provided, the CPU that initially triggers panic forwards the panic context to the target CPU via IPI, which then proceeds with the normal panic and kexec flow. The IPI delivery is implemented as a weak function (panic_smp_redirect_cpu) so architectures with NMI support can override it for more reliable delivery. If the specified CPU is invalid, offline, or a panic is already in progress on another CPU, the redirection is skipped and panic continues on the current CPU. [pnina.feder@mobileye.com: fix unused variable warning] Link: https://lkml.kernel.org/r/20260126122618.2967950-1-pnina.feder@mobileye.com Link: https://lkml.kernel.org/r/20260122102457.1154599-1-pnina.feder@mobileye.com Signed-off-by: Pnina Feder <pnina.feder@mobileye.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: Baoquan He <bhe@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mel Gorman <mgorman@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-02-03Merge branch 'v6.19-rc8'Peter Zijlstra
Update to avoid conflicts with /urgent patches. Signed-off-by: Peter Zijlstra <peterz@infradead.org>
2026-02-02Documentation: document liveupdate cmdline parameterLi Chen
liveupdate is used to enable Live Update Orchestrator (LUO) early during boot. Add it to kernel-parameters.txt so users can discover and use it. Link: https://lkml.kernel.org/r/20260130112036.359806-1-me@linux.beauty Signed-off-by: Li Chen <me@linux.beauty> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Borislav Petkov (AMD)" <bp@alien8.de> Cc: Frank van der Linden <fvdl@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kees Cook <kees@kernel.org> Cc: Li RongQing <lirongqing@baidu.com> Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-30docs: trusted-encryped: add PKWM as a new trust sourceNayna Jain
Update Documentation/security/keys/trusted-encrypted.rst and Documentation/ admin-guide/kernel-parameters.txt with PowerVM Key Wrapping Module (PKWM) as a new trust source Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Signed-off-by: Srish Srinivasan <ssrish@linux.ibm.com> Tested-by: Nayna Jain <nayna@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20260127145228.48320-7-ssrish@linux.ibm.com
2026-01-29riscv: add kernel command line option to opt out of user CFIDeepak Gupta
Add a kernel command line option to disable part or all of user CFI. User backward CFI and forward CFI can be controlled independently. The kernel command line parameter "riscv_nousercfi" can take the following values: - "all" : Disable forward and backward cfi both - "bcfi" : Disable backward cfi - "fcfi" : Disable forward cfi Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-21-b55691eacf4f@rivosinc.com [pjw@kernel.org: fixed warnings from checkpatch; cleaned up patch description, doc, printk text] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-22rseq: Provide static branch for time slice extensionsThomas Gleixner
Guard the time slice extension functionality with a static key, which can be disabled on the kernel command line. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20251215155708.733429292@linutronix.de
2026-01-20watchdog: softlockup: panic when lockup duration exceeds N thresholdsLi RongQing
The softlockup_panic sysctl is currently a binary option: panic immediately or never panic on soft lockups. Panicking on any soft lockup, regardless of duration, can be overly aggressive for brief stalls that may be caused by legitimate operations. Conversely, never panicking may allow severe system hangs to persist undetected. Extend softlockup_panic to accept an integer threshold, allowing the kernel to panic only when the normalized lockup duration exceeds N watchdog threshold periods. This provides finer-grained control to distinguish between transient delays and persistent system failures. The accepted values are: - 0: Don't panic (unchanged) - 1: Panic when duration >= 1 * threshold (20s default, original behavior) - N > 1: Panic when duration >= N * threshold (e.g., 2 = 40s, 3 = 60s.) The original behavior is preserved for values 0 and 1, maintaining full backward compatibility while allowing systems to tolerate brief lockups while still catching severe, persistent hangs. [lirongqing@baidu.com: v2] Link: https://lkml.kernel.org/r/20251218074300.4080-1-lirongqing@baidu.com Link: https://lkml.kernel.org/r/20251216074521.2796-1-lirongqing@baidu.com Signed-off-by: Li RongQing <lirongqing@baidu.com> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Lance Yang <lance.yang@linux.dev> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Song Liu <song@kernel.org> Cc: Stanislav Fomichev <sdf@fomichev.me> Cc: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-19dm-verity: add dm-verity keyringChristian Brauner
Add a dedicated ".dm-verity" keyring for root hash signature verification, similar to the ".fs-verity" keyring used by fs-verity. By default the keyring is unused retaining the exact same old behavior. For systems that provision additional keys only intended for dm-verity images during boot, the dm_verity.keyring_unsealed=1 kernel parameter leaves the keyring open. We want to use this in systemd as a way add keys during boot that are only used for creating dm-verity devices for later mounting and nothing else. The discoverable disk image (DDI) spec at [1] heavily relies on dm-verity and we would like to expand this even more. This will allow us to do that in a fully backward compatible way. Once provisioning is complete, userspace restricts and activates it for dm-verity verification. If userspace fully seals the keyring then it gains the guarantee that no new keys can be added. Link: https://uapi-group.org/specifications/specs/discoverable_partitions_specification [1] Co-developed-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2026-01-17x86/acpi: Add acpi=spcr to use SPCR-provided default consoleShenghao Yang
The SPCR provided console on x86 is only available as a boot console when earlycon is provided on the kernel command line, and will not be present in /proc/consoles. While it's possible to retain the boot console with the keep_bootcon parameter, that leaves the console using the less efficient 8250_early driver. Users wanting to use the firmware suggested console (to avoid maintaining unique serial console parameters for different server models in large fleets) with the conventional driver have to parse the kernel log for the console parameters and reinsert them. [ 0.005091] ACPI: SPCR 0x000000007FFB5000 000059 (v04 ALASKA A M I 01072009 INTL 20250404) [ 0.073387] ACPI: SPCR: console: uart,io,0x3f8,115200 In commit 0231d00082f6 ("ACPI: SPCR: Make SPCR available to x86")¹ the SPCR console was only added as an option for earlycon but not as an ordinary console so users don't see console output changes. So users can opt in to an automatic SPCR console, make ACPI init add it if acpi=spcr is set. ¹https://lore.kernel.org/lkml/20180118150951.28964-1-prarit@redhat.com/ [ bp: Touchups. ] Signed-off-by: Shenghao Yang <me@shenghaoyang.info> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20260117072827.355360-1-me@shenghaoyang.info
2026-01-16docs: make kptr_restrict and hash_pointers reference each otherMarc Herbert
vsprintf.c uses a mix of the `kernel.kptr_restrict` sysctl and the `hash_pointers` boot param to control pointer hashing. But that wasn't possible to tell without looking at the source code. They have a different focus and purpose. To avoid wasting the time of users trying to use one instead of the other, simply have them reference each other in the Documentation. Signed-off-by: Marc Herbert <marc.herbert@linux.intel.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260107-doc-hash-ptr-v2-1-cb4c161218d7@linux.intel.com>
2026-01-14docs: kernel-parameters: add kfence parametersMarco Elver
Add a brief summary for KFENCE's kernel command-line parameters in admin-guide/kernel-parameters. Link: https://lkml.kernel.org/r/20251222150018.1349672-1-elver@google.com Signed-off-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-14xen: introduce xen_console_io optionStefano Stabellini
Xen can support console_io hypercalls for any domains, not just dom0, depending on DEBUG and XSM policies. These hypercalls can be very useful for development and debugging. Introduce a kernel command line option xen_console_io to enable the usage of console_io hypercalls for any domain upon request. When xen_console_io is not specified, the current behavior is retained. Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com> Message-ID: <alpine.DEB.2.22.394.2601131522540.992863@ubuntu-linux-20-04-desktop>
2026-01-12initrd: remove deprecated code path (linuxrc)Askar Safin
Remove linuxrc initrd code path, which was deprecated in 2020. Initramfs and (non-initial) RAM disks (i. e. brd) still work. Both built-in and bootloader-supplied initramfs still work. Non-linuxrc initrd code path (i. e. using /dev/ram as final root filesystem) still works, but I put deprecation message into it. Also I deprecate command line parameters "noinitrd" and "ramdisk_start=". Signed-off-by: Askar Safin <safinaskar@gmail.com> Link: https://patch.msgid.link/20251119222407.3333257-3-safinaskar@gmail.com Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-01-10iommu: Add page_ext for IOMMU_DEBUG_PAGEALLOCMostafa Saleh
Add a new config IOMMU_DEBUG_PAGEALLOC, which registers new data to page_ext. This config will be used by the IOMMU API to track pages mapped in the IOMMU to catch drivers trying to free kernel memory that they still map in their domains, causing all types of memory corruption. This behaviour is disabled by default and can be enabled using kernel cmdline iommu.debug_pagealloc. Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Reviewed-by: Pranjal Shrivastava <praan@google.com> Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2026-01-09x86/resctrl: Add energy/perf choices to rdt boot optionTony Luck
Legacy resctrl features are enumerated by X86_FEATURE_* flags. These may be overridden by quirks to disable features in the case of errata. Users can use kernel command line options to either disable a feature, or to force enable a feature that was disabled by a quirk. A different approach is needed for hardware features that do not have an X86_FEATURE_* flag. Update parsing of the "rdt=" boot parameter to call the telemetry driver directly to handle new "perf" and "energy" options that controls activation of telemetry monitoring of the named type. By itself a "perf" or "energy" option controls the forced enabling or disabling (with ! prefix) of all event groups of the named type. A ":guid" suffix allows for fine grained control per event group. [ bp: s/intel_aet_option/intel_handle_aet_option/g ] 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://lore.kernel.org/20251217172121.12030-1-tony.luck@intel.com
2026-01-08KVM: x86/pmu: Expose enable_mediated_pmu parameter to user spaceDapeng Mi
Expose enable_mediated_pmu parameter to user space, i.e. allow userspace to enable/disable mediated vPMU support. Document the mediated versus perf-based behavior as part of the kernel-parameters.txt entry, and opportunistically add an entry for the core enable_pmu param as well. Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Signed-off-by: Mingwei Zhang <mizhang@google.com> Tested-by: Xudong Hao <xudong.hao@intel.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Tested-by: Manali Shukla <manali.shukla@amd.com> Link: https://patch.msgid.link/20251206001720.468579-34-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2026-01-06Documentation/kernel-parameters: Add tsa under mitigations=offYu Liao
On X86 AMD systems, mitigations=off also disables the Transient Scheduler Attacks (TSA) mitigation. Add it to the list. Signed-off-by: Yu Liao <liaoyu.ly@bytedance.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20251225121438.38427-1-liaoyu.ly@bytedance.com>
2026-01-01rcu: Clean up after the SRCU-fastification of RCU Tasks TracePaul E. McKenney
Now that RCU Tasks Trace has been re-implemented in terms of SRCU-fast, the ->trc_ipi_to_cpu, ->trc_blkd_cpu, ->trc_blkd_node, ->trc_holdout_list, and ->trc_reader_special task_struct fields are no longer used. In addition, the rcu_tasks_trace_qs(), rcu_tasks_trace_qs_blkd(), exit_tasks_rcu_finish_trace(), and rcu_spawn_tasks_trace_kthread(), show_rcu_tasks_trace_gp_kthread(), rcu_tasks_trace_get_gp_data(), rcu_tasks_trace_torture_stats_print(), and get_rcu_tasks_trace_gp_kthread() functions and all the other functions that they invoke are no longer used. Also, the TRC_NEED_QS and TRC_NEED_QS_CHECKED CPP macros are no longer used. Neither are the rcu_tasks_trace_lazy_ms and rcu_task_ipi_delay rcupdate module parameters and the TASKS_TRACE_RCU_READ_MB Kconfig option. This commit therefore removes all of them. [ paulmck: Apply Alexei Starovoitov feedback. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: bpf@vger.kernel.org Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
2025-12-15init: remove deprecated "load_ramdisk" and "prompt_ramdisk" command line ↵Askar Safin
parameters ...which do nothing. They were deprecated (in documentation) in 6b99e6e6aa62 ("Documentation/admin-guide: blockdev/ramdisk: remove use of "rdev"") in 2020 and in kernel messages in c8376994c86c ("initrd: remove support for multiple floppies") in 2020. Signed-off-by: Askar Safin <safinaskar@gmail.com> Link: https://patch.msgid.link/20251119222407.3333257-2-safinaskar@gmail.com Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-12-15ata: libata: Add libata.force parameter max_secNiklas Cassel
Add a new libata.force parameter called max_sec. The parameter can take an arbitrary value using the format: libata.force=max_sec=<number of 512B sectors> e.g. libata.force=max_sec=8191 or libata.force=max_sec=2048 This will allow the user to set an arbitrary maximum command size (dev->max_sectors) using libata.force. We cannot remove the existing libata.force parameters "max_sec_128" and "max_sec_1024", as these are a part of the exising user facing API. Signed-off-by: Niklas Cassel <cassel@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
2025-12-07Merge tag 'memblock-6.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock Pull memblock update from Mike Rapoport: "Introduce a 'check_pages' boot parameter to decouple simple checks for page state on allocation and free from CONFIG_DEBUG_VM. This allows enabling page checking without building kernel with CONFIG_DEBUG_VM or forcing init_on_{alloc, free} or other heavier mechanisms" * tag 'memblock-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock: mm/mm_init: Introduce a boot parameter for check_pages
2025-12-06Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko) fixes a build issue and does some cleanup in ib/sys_info.c - "Implement mul_u64_u64_div_u64_roundup()" (David Laight) enhances the 64-bit math code on behalf of a PWM driver and beefs up the test module for these library functions - "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich) makes BPF symbol names, sizes, and line numbers available to the GDB debugger - "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang) adds a sysctl which can be used to cause additional info dumping when the hung-task and lockup detectors fire - "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu) adds a general base64 encoder/decoder to lib/ and migrates several users away from their private implementations - "rbree: inline rb_first() and rb_last()" (Eric Dumazet) makes TCP a little faster - "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin) reworks the KEXEC Handover interfaces in preparation for Live Update Orchestrator (LUO), and possibly for other future clients - "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin) increases the flexibility of KEXEC Handover. Also preparation for LUO - "Live Update Orchestrator" (Pasha Tatashin) is a major new feature targeted at cloud environments. Quoting the cover letter: This series introduces the Live Update Orchestrator, a kernel subsystem designed to facilitate live kernel updates using a kexec-based reboot. This capability is critical for cloud environments, allowing hypervisors to be updated with minimal downtime for running virtual machines. LUO achieves this by preserving the state of selected resources, such as memory, devices and their dependencies, across the kernel transition. As a key feature, this series includes support for preserving memfd file descriptors, which allows critical in-memory data, such as guest RAM or any other large memory region, to be maintained in RAM across the kexec reboot. Mike Rappaport merits a mention here, for his extensive review and testing work. - "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain) moves the kexec and kdump sysfs entries from /sys/kernel/ to /sys/kernel/kexec/ and adds back-compatibility symlinks which can hopefully be removed one day - "kho: fixes for vmalloc restoration" (Mike Rapoport) fixes a BUG which was being hit during KHO restoration of vmalloc() regions * tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits) calibrate: update header inclusion Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()" vmcoreinfo: track and log recoverable hardware errors kho: fix restoring of contiguous ranges of order-0 pages kho: kho_restore_vmalloc: fix initialization of pages array MAINTAINERS: TPM DEVICE DRIVER: update the W-tag init: replace simple_strtoul with kstrtoul to improve lpj_setup KHO: fix boot failure due to kmemleak access to non-PRESENT pages Documentation/ABI: new kexec and kdump sysfs interface Documentation/ABI: mark old kexec sysfs deprecated kexec: move sysfs entries to /sys/kernel/kexec test_kho: always print restore status kho: free chunks using free_page() instead of kfree() selftests/liveupdate: add kexec test for multiple and empty sessions selftests/liveupdate: add simple kexec-based selftest for LUO selftests/liveupdate: add userspace API selftests docs: add documentation for memfd preservation via LUO mm: memfd_luo: allow preserving memfd liveupdate: luo_file: add private argument to store runtime state mm: shmem: export some functions to internal.h ...
2025-12-05Merge tag 'driver-core-6.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core Pull driver core updates from Danilo Krummrich: "Arch Topology: - Move parse_acpi_topology() from arm64 to common code for reuse in RISC-V CPU: - Expose housekeeping CPUs through /sys/devices/system/cpu/housekeeping - Print a newline (or 0x0A) instead of '(null)' reading /sys/devices/system/cpu/nohz_full when nohz_full= is not set debugfs - Remove (broken) 'no-mount' mode - Remove redundant access mode checks in debugfs_get_tree() and debugfs_create_*() functions Devres: - Remove unused devm_free_percpu() helper - Move devm_alloc_percpu() from device.h to devres.h Firmware Loader: - Replace simple_strtol() with kstrtoint() - Do not call cancel_store() when no upload is in progress kernfs: - Increase struct super_block::maxbytes to MAX_LFS_FILESIZE - Fix a missing unwind path in __kernfs_new_node() Misc: - Increase the name size in struct auxiliary_device_id to 40 characters - Replace system_unbound_wq with system_dfl_wq and add WQ_PERCPU to alloc_workqueue() Platform: - Replace ERR_PTR() with IOMEM_ERR_PTR() in platform ioremap functions Rust: - Auxiliary: - Unregister auxiliary device on parent device unbind - Move parent() to impl Device; implement device context aware parent() for Device<Bound> - Illustrate how to safely obtain a driver's device private data when calling from an auxiliary driver into the parant device driver - DebugFs: - Implement support for binary large objects - Device: - Let probe() return the driver's device private data as pinned initializer, i.e. impl PinInit<Self, Error> - Implement safe accessor for a driver's device private data for Device<Bound> (returned reference can't out-live driver binding and guarantees the correct private data type) - Implement AsBusDevice trait, to be used by class device abstractions to derive the bus device type of the parent device - DMA: - Store raw pointer of allocation as NonNull - Use start_ptr() and start_ptr_mut() to inherit correct mutability of self - FS: - Add file::Offset type alias - I2C: - Add abstractions for I2C device / driver infrastructure - Implement abstractions for manual I2C device registrations - I/O: - Use "kernel vertical" style for imports - Define ResourceSize as resource_size_t - Move ResourceSize to top-level I/O module - Add type alias for phys_addr_t - Implement Rust version of read_poll_timeout_atomic() - PCI: - Use "kernel vertical" style for imports - Move I/O and IRQ infrastructure to separate files - Add support for PCI interrupt vectors - Implement TryInto<IrqRequest<'a>> for IrqVector<'a> to convert an IrqVector bound to specific pci::Device into an IrqRequest bound to the same pci::Device's parent Device - Leverage pin_init_scope() to get rid of redundant Result in IRQ methods - PinInit: - Add {pin_}init_scope() to execute code before creating an initializer - Platform: - Leverage pin_init_scope() to get rid of redundant Result in IRQ methods - Timekeeping: - Implement abstraction of udelay() - Uaccess: - Implement read_slice_partial() and read_slice_file() for UserSliceReader - Implement write_slice_partial() and write_slice_file() for UserSliceWriter sysfs: - Prepare the constification of struct attribute" * tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (75 commits) rust: pci: fix build failure when CONFIG_PCI_MSI is disabled debugfs: Fix default access mode config check debugfs: Remove broken no-mount mode debugfs: Remove redundant access mode checks driver core: Check drivers_autoprobe for all added devices driver core: WQ_PERCPU added to alloc_workqueue users driver core: replace use of system_unbound_wq with system_dfl_wq tick/nohz: Expose housekeeping CPUs in sysfs tick/nohz: avoid showing '(null)' if nohz_full= not set sysfs/cpu: Use DEVICE_ATTR_RO for nohz_full attribute kernfs: fix memory leak of kernfs_iattrs in __kernfs_new_node fs/kernfs: raise sb->maxbytes to MAX_LFS_FILESIZE mod_devicetable: Bump auxiliary_device_id name size sysfs: simplify attribute definition macros samples/kobject: constify 'struct foo_attribute' samples/kobject: add is_visible() callback to attribute group sysfs: attribute_group: enable const variants of is_visible() sysfs: introduce __SYSFS_FUNCTION_ALTERNATIVE() sysfs: transparently handle const pointers in ATTRIBUTE_GROUPS() sysfs: attribute_group: allow registration of const attribute ...
2025-12-05Merge tag 'powerpc-6.19-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Restore clearing of MSR[RI] at interrupt/syscall exit on 32-bit - Fix unpaired stwcx on interrupt exit on 32-bit - Fix race condition leading to double list-add in mac_hid_toggle_emumouse() - Fix mprotect on book3s 32-bit - Fix SLB multihit issue during SLB preload with 64-bit hash MMU - Add support for crashkernel CMA reservation - Add die_id and die_cpumask for Power10 & later to expose chip hemispheres - A series of minor fixes and improvements to the hash SLB code Thanks to Antonio Alvarez Feijoo, Ben Collins, Bhaskar Chowdhury, Christophe Leroy, Daniel Thompson, Dave Vasilevsky, Donet Tom, J. Neuschäfer, Kunwu Chan, Long Li, Naresh Kamboju, Nathan Chancellor, Ritesh Harjani (IBM), Shirisha G, Shrikanth Hegde, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Thomas Zimmermann, Venkat Rao Bagalkote, and Vishal Chourasia. * tag 'powerpc-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (32 commits) macintosh/via-pmu-backlight: Include <linux/fb.h> and <linux/of.h> powerpc/powermac: backlight: Include <linux/of.h> powerpc/64s/slb: Add no_slb_preload early cmdline param powerpc/64s/slb: Make preload_add return type as void powerpc/ptdump: Dump PXX level info for kernel_page_tables powerpc/64s/pgtable: Enable directMap counters in meminfo for Hash powerpc/64s/hash: Update directMap page counters for Hash powerpc/64s/hash: Hash hpt_order should be only available with Hash MMU powerpc/64s/hash: Improve hash mmu printk messages powerpc/64s/hash: Fix phys_addr_t printf format in htab_initialize() powerpc/64s/ptdump: Fix kernel_hash_pagetable dump for ISA v3.00 HPTE format powerpc/64s/hash: Restrict stress_hpt_struct memblock region to within RMA limit powerpc/64s/slb: Fix SLB multihit issue during SLB preload powerpc, mm: Fix mprotect on book3s 32-bit powerpc/smp: Expose die_id and die_cpumask powerpc/83xx: Add a null pointer check to mcu_gpiochip_add arch:powerpc:tools This file was missing shebang line, so added it kexec: Include kernel-end even without crashkernel powerpc: p2020: Rename wdt@ nodes to watchdog@ powerpc: 86xx: Rename wdt@ nodes to watchdog@ ...
2025-12-04mm/mm_init: Introduce a boot parameter for check_pagesJoshua Hahn
Use-after-free and double-free bugs can be very difficult to track down. The kernel is good at tracking these and preventing bad pages from being used/created through simple checks gated behind "check_pages_enabled". Currently, the only ways to enable this flag is by building with CONFIG_DEBUG_VM, or as a side effect of other checks such as init_on_{alloc, free}, page_poisoning, or debug_pagealloc among others. These solutions are powerful, but may often be too coarse in balancing the performance vs. safety that a user may want, particularly in latency-sensitive production environments. Introduce a new boot parameter "check_pages", which enables page checking with no other side effects. It takes kstrbool-able inputs as an argument (i.e. 0/1, true/false, on/off, ...). This patch is backwards-compatible; setting CONFIG_DEBUG_VM still enables page checking. Acked-by: SeongJae Park <sj@kernel.org> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Joshua Hahn <joshua.hahnjy@gmail.com> Link: https://patch.msgid.link/20251201180739.2330474-1-joshua.hahnjy@gmail.com Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
2025-12-03Merge tag 'docs-6.19' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "This has been another busy cycle for documentation, with a lot of build-system thrashing. That work should slow down from here on out. - The various scripts and tools for documentation were spread out in several directories; now they are (almost) all coalesced under tools/docs/. The holdout is the kernel-doc script, which cannot be easily moved without some further thought. - As the amount of Python code increases, we are accumulating modules that are imported by multiple programs. These modules have been pulled together under tools/lib/python/ -- at least, for documentation-related programs. There is other Python code in the tree that might eventually want to move toward this organization. - The Perl kernel-doc.pl script has been removed. It is no longer used by default, and nobody has missed it, least of all anybody who actually had to look at it. - The docs build was controlled by a complex mess of makefilese that few dared to touch. Mauro has moved that logic into a new program (tools/docs/sphinx-build-wrapper) that, with any luck at all, will be far easier to understand and maintain. - The get_feat.pl program, used to access information under Documentation/features/, has been rewritten in Python, bringing an end to the use of Perl in the docs subsystem. - The top-level README file has been reorganized into a more reader-friendly presentation. - A lot of Chinese translation additions - Typo fixes and documentation updates as usual" * tag 'docs-6.19' of git://git.lwn.net/linux: (164 commits) docs: makefile: move rustdoc check to the build wrapper README: restructure with role-based documentation and guidelines docs: kdoc: various fixes for grammar, spelling, punctuation docs: kdoc_parser: use '@' for Excess enum value docs: submitting-patches: Clarify that removal of Acks needs explanation too docs: kdoc_parser: add data/function attributes to ignore docs: MAINTAINERS: update Mauro's files/paths docs/zh_CN: Add wd719x.rst translation docs/zh_CN: Add libsas.rst translation get_feat.pl: remove it, as it got replaced by get_feat.py Documentation/sphinx/kernel_feat.py: use class directly tools/docs/get_feat.py: convert get_feat.pl to Python Documentation/admin-guide: fix typo and comment in cscope example docs/zh_CN: Add data-integrity.rst translation docs/zh_CN: Add blk-mq.rst translation docs/zh_CN: Add block/index.rst translation docs/zh_CN: Update the Chinese translation of kbuild.rst docs: bring some order to our Python module hierarchy docs: Move the python libraries to tools/lib/python Documentation/kernel-parameters: Move the kernel build options ...
2025-12-02Merge tag 'pm-6.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "There are quite a few interesting things here, including new hardware support, new features, some bug fixes and documentation updates. In addition, there are a usual bunch of minor fixes and cleanups all over. In the new hardware support category, there are intel_pstate and intel_rapl driver updates to support new processors, Panther Lake, Wildcat Lake, Noval Lake, and Diamond Rapids in the OOB mode, OPP and bandwidth allocation support in the tegra186 cpufreq driver, and JH7110S SOC support in dt-platdev cpufreq. The new features are the PM QoS CPU latency limit for suspend-to-idle, the netlink support for the energy model management, support for terminating system suspend via a wakeup event during the sync of file systems, configurable number of hibernation compression threads, the runtime PM auto-cleanup macros, and the "poweroff" PM event that is expected to be used during system shutdown. Bugs are mostly fixed in cpuidle governors, but there are also fixes elsewhere, like in the amd-pstate cpufreq driver. Documentation updates include, but are not limited to, a new doc on debugging shutdown hangs, cross-referencing fixes and cleanups in the intel_pstate documentation, and updates of comments in the core hibernation code. Specifics: - Introduce and document a QoS limit on CPU exit latency during wakeup from suspend-to-idle (Ulf Hansson) - Add support for building libcpupower statically (Zuo An) - Add support for sending netlink notifications to user space on energy model updates (Changwoo Mini, Peng Fan) - Minor improvements to the Rust OPP interface (Tamir Duberstein) - Fixes to scope-based pointers in the OPP library (Viresh Kumar) - Use residency threshold in polling state override decisions in the menu cpuidle governor (Aboorva Devarajan) - Add sanity check for exit latency and target residency in the cpufreq core (Rafael Wysocki) - Use this_cpu_ptr() where possible in the teo governor (Christian Loehle) - Rework the handling of tick wakeups in the teo cpuidle governor to increase the likelihood of stopping the scheduler tick in the cases when tick wakeups can be counted as non-timer ones (Rafael Wysocki) - Fix a reverse condition in the teo cpuidle governor and drop a misguided target residency check from it (Rafael Wysocki) - Clean up multiple minor defects in the teo cpuidle governor (Rafael Wysocki) - Update header inclusion to make it follow the Include What You Use principle (Andy Shevchenko) - Enable MSR-based RAPL PMU support in the intel_rapl power capping driver and arrange for using it on the Panther Lake and Wildcat Lake processors (Kuppuswamy Sathyanarayanan) - Add support for Nova Lake and Wildcat Lake processors to the intel_rapl power capping driver (Kaushlendra Kumar, Srinivas Pandruvada) - Add OPP and bandwidth support for Tegra186 (Aaron Kling) - Optimizations for parameter array handling in the amd-pstate cpufreq driver (Mario Limonciello) - Fix for mode changes with offline CPUs in the amd-pstate cpufreq driver (Gautham Shenoy) - Preserve freq_table_sorted across suspend/hibernate in the cpufreq core (Zihuan Zhang) - Adjust energy model rules for Intel hybrid platforms in the intel_pstate cpufreq driver and improve printing of debug messages in it (Rafael Wysocki) - Replace deprecated strcpy() in cpufreq_unregister_governor() (Thorsten Blum) - Fix duplicate hyperlink target errors in the intel_pstate cpufreq driver documentation and use :ref: directive for internal linking in it (Swaraj Gaikwad, Bagas Sanjaya) - Add Diamond Rapids OOB mode support to the intel_pstate cpufreq driver (Kuppuswamy Sathyanarayanan) - Use mutex guard for driver locking in the intel_pstate driver and eliminate some code duplication from it (Rafael Wysocki) - Replace udelay() with usleep_range() in ACPI cpufreq (Kaushlendra Kumar) - Minor improvements to various cpufreq drivers (Christian Marangi, Hal Feng, Jie Zhan, Marco Crivellari, Miaoqian Lin, and Shuhao Fu) - Replace snprintf() with scnprintf() in show_trace_dev_match() (Kaushlendra Kumar) - Fix memory allocation error handling in pm_vt_switch_required() (Malaya Kumar Rout) - Introduce CALL_PM_OP() macro and use it to simplify code in generic PM operations (Kaushlendra Kumar) - Add module param to backtrace all CPUs in the device power management watchdog (Sergey Senozhatsky) - Rework message printing in swsusp_save() (Rafael Wysocki) - Make it possible to change the number of hibernation compression threads (Xueqin Luo) - Clarify that only cgroup1 freezer uses PM freezer (Tejun Heo) - Add document on debugging shutdown hangs to PM documentation and correct a mistaken configuration option in it (Mario Limonciello) - Shut down wakeup source timer before removing the wakeup source from the list (Kaushlendra Kumar, Rafael Wysocki) - Introduce new PMSG_POWEROFF event for system shutdown handling with the help of PM device callbacks (Mario Limonciello) - Make pm_test delay interruptible by wakeup events (Riwen Lu) - Clean up kernel-doc comment style usage in the core hibernation code and remove unuseful comments from it (Sunday Adelodun, Rafael Wysocki) - Add support for handling wakeup events and aborting the suspend process while it is syncing file systems (Samuel Wu, Rafael Wysocki) - Add WQ_UNBOUND to pm_wq workqueue (Marco Crivellari) - Add runtime PM wrapper macros for ACQUIRE()/ACQUIRE_ERR() and use them in the PCI core and the ACPI TAD driver (Rafael Wysocki) - Improve runtime PM in the ACPI TAD driver (Rafael Wysocki) - Update pm_runtime_allow/forbid() documentation (Rafael Wysocki) - Fix typos in runtime.c comments (Malaya Kumar Rout) - Move governor.h from devfreq under include/linux/ and rename to devfreq-governor.h to allow devfreq governor definitions in out of drivers/devfreq/ (Dmitry Baryshkov) - Use min() to improve readability in tegra30-devfreq.c (Thorsten Blum) - Fix potential use-after-free issue of OPP handling in hisi_uncore_freq.c (Pengjie Zhang) - Fix typo in DFSO_DOWNDIFFERENTIAL macro name in governor_simpleondemand.c in devfreq (Riwen Lu)" * tag 'pm-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (96 commits) PM / devfreq: Fix typo in DFSO_DOWNDIFFERENTIAL macro name cpuidle: Warn instead of bailing out if target residency check fails cpuidle: Update header inclusion Documentation: power/cpuidle: Document the CPU system wakeup latency QoS cpuidle: Respect the CPU system wakeup QoS limit for cpuidle sched: idle: Respect the CPU system wakeup QoS limit for s2idle pmdomain: Respect the CPU system wakeup QoS limit for cpuidle pmdomain: Respect the CPU system wakeup QoS limit for s2idle PM: QoS: Introduce a CPU system wakeup QoS limit cpuidle: governors: teo: Add missing space to the description PM: hibernate: Extra cleanup of comments in swap handling code PM / devfreq: tegra30: use min to simplify actmon_cpu_to_emc_rate PM / devfreq: hisi: Fix potential UAF in OPP handling PM / devfreq: Move governor.h to a public header location powercap: intel_rapl: Enable MSR-based RAPL PMU support powercap: intel_rapl: Prepare read_raw() interface for atomic-context callers cpufreq: qcom-nvmem: fix compilation warning for qcom_cpufreq_ipq806x_match_list PM: sleep: Call pm_sleep_fs_sync() instead of ksys_sync_helper() PM: sleep: Add support for wakeup during filesystem sync cpufreq: ACPI: Replace udelay() with usleep_range() ...
2025-12-02Merge tag 'x86_cache_for_v6.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Borislav Petkov: - Add support for AMD's Smart Data Cache Injection feature which allows for direct insertion of data from I/O devices into the L3 cache, thus bypassing DRAM and saving its bandwidth; the resctrl side of the feature allows the size of the L3 used for data injection to be controlled - Add Intel Clearwater Forest to the list of CPUs which support Sub-NUMA clustering - Other fixes and cleanups * tag 'x86_cache_for_v6.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: fs/resctrl: Update bit_usage to reflect io_alloc fs/resctrl: Introduce interface to modify io_alloc capacity bitmasks fs/resctrl: Modify struct rdt_parse_data to pass mode and CLOSID fs/resctrl: Introduce interface to display io_alloc CBMs fs/resctrl: Add user interface to enable/disable io_alloc feature fs/resctrl: Introduce interface to display "io_alloc" support x86,fs/resctrl: Implement "io_alloc" enable/disable handlers x86,fs/resctrl: Detect io_alloc feature x86/resctrl: Add SDCIAE feature in the command line options x86/cpufeatures: Add support for L3 Smart Data Cache Injection Allocation Enforcement fs/resctrl: Consider sparse masks when initializing new group's allocation x86/resctrl: Support Sub-NUMA Cluster (SNC) mode on Clearwater Forest
2025-11-27debugfs: Remove broken no-mount modeAaron Thompson
debugfs access modes were added in Linux 5.10 (Dec 2020) [1], but the no-mount mode has behaved effectively the same as the off mode since Linux 5.12 (Apr 2021) [2]. The only difference is the specific error code returned by the debugfs_create_* functions, which is -ENOENT in no-mount mode and -EPERM in off mode. Given that no-mount hasn't worked for several years with no complaints, just remove it. [1] a24c6f7bc923 ("debugfs: Add access restriction option") [2] bc6de804d36b ("debugfs: be more robust at handling improper input in debugfs_lookup()") 56348560d495 ("debugfs: do not attempt to create a new file before the filesystem is initalized") Signed-off-by: Aaron Thompson <dev@aaront.org> Link: https://patch.msgid.link/20251120102222.18371-3-dev@null.aaront.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>