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20 hoursMerge tag 'x86-urgent-2025-12-21' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: - Fix FPU core dumps on certain CPU models - Fix htmldocs build warning - Export TLB tracing event name via header - Remove unused constant from <linux/mm_types.h> - Fix comments - Fix whitespace noise in documentation - Fix variadic structure's definition to un-confuse UBSAN - Fix posted MSI interrupts irq_retrigger() bug - Fix asm build failure with older GCC builds * tag 'x86-urgent-2025-12-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bug: Fix old GCC compile fails x86/msi: Make irq_retrigger() functional for posted MSI x86/platform/uv: Fix UBSAN array-index-out-of-bounds mm: Remove tlb_flush_reason::NR_TLB_FLUSH_REASONS from <linux/mm_types.h> x86/mm/tlb/trace: Export the TLB_REMOTE_WRONG_CPU enum in <trace/events/tlb.h> x86/sgx: Remove unmatched quote in __sgx_encl_extend function comment x86/boot/Documentation: Fix whitespace noise in boot.rst x86/fpu: Fix FPU state core dump truncation on CPUs with no extended xfeatures x86/boot/Documentation: Fix htmldocs build warning due to malformed table in boot.rst
5 daysx86/msi: Make irq_retrigger() functional for posted MSIThomas Gleixner
Luigi reported that retriggering a posted MSI interrupt does not work correctly. The reason is that the retrigger happens at the vector domain by sending an IPI to the actual vector on the target CPU. That works correctly exactly once because the posted MSI interrupt chip does not issue an EOI as that's only required for the posted MSI notification vector itself. As a consequence the vector becomes stale in the ISR, which not only affects this vector but also any lower priority vector in the affected APIC because the ISR bit is not cleared. Luigi proposed to set the vector in the remap PIR bitmap and raise the posted MSI notification vector. That works, but that still does not cure a related problem: If there is ever a stray interrupt on such a vector, then the related APIC ISR bit becomes stale due to the lack of EOI as described above. Unlikely to happen, but if it happens it's not debuggable at all. So instead of playing games with the PIR, this can be actually solved for both cases by: 1) Keeping track of the posted interrupt vector handler state 2) Implementing a posted MSI specific irq_ack() callback which checks that state. If the posted vector handler is inactive it issues an EOI, otherwise it delegates that to the posted handler. This is correct versus affinity changes and concurrent events on the posted vector as the actual handler invocation is serialized through the interrupt descriptor lock. Fixes: ed1e48ea4370 ("iommu/vt-d: Enable posted mode for device MSIs") Reported-by: Luigi Rizzo <lrizzo@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Luigi Rizzo <lrizzo@google.com> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20251125214631.044440658@linutronix.de Closes: https://lore.kernel.org/lkml/20251124104836.3685533-1-lrizzo@google.com
6 daysMerge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfLinus Torvalds
Pull bpf fixes from Alexei Starovoitov: - Fix BPF builds due to -fms-extensions. selftests (Alexei Starovoitov), bpftool (Quentin Monnet). - Fix build of net/smc when CONFIG_BPF_SYSCALL=y, but CONFIG_BPF_JIT=n (Geert Uytterhoeven) - Fix livepatch/BPF interaction and support reliable unwinding through BPF stack frames (Josh Poimboeuf) - Do not audit capability check in arm64 JIT (Ondrej Mosnacek) - Fix truncated dmabuf BPF iterator reads (T.J. Mercier) - Fix verifier assumptions of bpf_d_path's output buffer (Shuran Liu) - Fix warnings in libbpf when built with -Wdiscarded-qualifiers under C23 (Mikhail Gavrilov) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: selftests/bpf: add regression test for bpf_d_path() bpf: Fix verifier assumptions of bpf_d_path's output buffer selftests/bpf: Add test for truncated dmabuf_iter reads bpf: Fix truncated dmabuf iterator reads x86/unwind/orc: Support reliable unwinding through BPF stack frames bpf: Add bpf_has_frame_pointer() bpf, arm64: Do not audit capability check in do_jit() libbpf: Fix -Wdiscarded-qualifiers under C23 bpftool: Fix build warnings due to MS extensions net: smc: SMC_HS_CTRL_BPF should depend on BPF_JIT selftests/bpf: Add -fms-extensions to bpf build flags
9 daysx86/sgx: Remove unmatched quote in __sgx_encl_extend function commentThorsten Blum
There is no opening quote. Remove the unmatched closing quote. Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kai Huang <kai.huang@intel.com> Link: https://patch.msgid.link/20251210125628.544916-1-thorsten.blum@linux.dev
12 daysx86/fpu: Fix FPU state core dump truncation on CPUs with no extended xfeaturesYongxin Liu
Zero can be a valid value of num_records. For example, on Intel Atom x6425RE, only x87 and SSE are supported (features 0, 1), and fpu_user_cfg.max_features is 3. The for_each_extended_xfeature() loop only iterates feature 2, which is not enabled, so num_records = 0. This is valid and should not cause core dump failure. The issue is that dump_xsave_layout_desc() returns 0 for both genuine errors (dump_emit() failure) and valid cases (no extended features). Use negative return values for errors and only abort on genuine failures. Fixes: ba386777a30b ("x86/elf: Add a new FPU buffer layout info to x86 core files") Signed-off-by: Yongxin Liu <yongxin.liu@windriver.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/20251210000219.4094353-2-yongxin.liu@windriver.com
12 daysx86/unwind/orc: Support reliable unwinding through BPF stack framesJosh Poimboeuf
BPF JIT programs and trampolines use a frame pointer, so the current ORC unwinder strategy of falling back to frame pointers (when an ORC entry is missing) usually works in practice when unwinding through BPF JIT stack frames. However, that frame pointer fallback is just a guess, so the unwind gets marked unreliable for live patching, which can cause livepatch transition stalls. Make the common case reliable by calling the bpf_has_frame_pointer() helper to detect the valid frame pointer region of BPF JIT programs and trampolines. Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder") Reported-by: Andrey Grodzovsky <andrey.grodzovsky@crowdstrike.com> Closes: https://lore.kernel.org/0e555733-c670-4e84-b2e6-abb8b84ade38@crowdstrike.com Acked-by: Song Liu <song@kernel.org> Acked-and-tested-by: Andrey Grodzovsky <andrey.grodzovsky@crowdstrike.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/r/a18505975662328c8ffb1090dded890c6f8c1004.1764818927.git.jpoimboe@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Jiri Olsa <jolsa@kernel.org>
14 daysMerge tag 'hyperv-next-signed-20251207' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux Pull hyperv updates from Wei Liu: - Enhancements to Linux as the root partition for Microsoft Hypervisor: - Support a new mode called L1VH, which allows Linux to drive the hypervisor running the Azure Host directly - Support for MSHV crash dump collection - Allow Linux's memory management subsystem to better manage guest memory regions - Fix issues that prevented a clean shutdown of the whole system on bare metal and nested configurations - ARM64 support for the MSHV driver - Various other bug fixes and cleanups - Add support for Confidential VMBus for Linux guest on Hyper-V - Secure AVIC support for Linux guests on Hyper-V - Add the mshv_vtl driver to allow Linux to run as the secure kernel in a higher virtual trust level for Hyper-V * tag 'hyperv-next-signed-20251207' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (58 commits) mshv: Cleanly shutdown root partition with MSHV mshv: Use reboot notifier to configure sleep state mshv: Add definitions for MSHV sleep state configuration mshv: Add support for movable memory regions mshv: Add refcount and locking to mem regions mshv: Fix huge page handling in memory region traversal mshv: Move region management to mshv_regions.c mshv: Centralize guest memory region destruction mshv: Refactor and rename memory region handling functions mshv: adjust interrupt control structure for ARM64 Drivers: hv: use kmalloc_array() instead of kmalloc() mshv: Add ioctl for self targeted passthrough hvcalls Drivers: hv: Introduce mshv_vtl driver Drivers: hv: Export some symbols for mshv_vtl static_call: allow using STATIC_CALL_TRAMP_STR() from assembly mshv: Extend create partition ioctl to support cpu features mshv: Allow mappings that overlap in uaddr mshv: Fix create memory region overlap check mshv: add WQ_PERCPU to alloc_workqueue users Drivers: hv: Use kmalloc_array() instead of kmalloc() ...
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 ...
2025-12-06Merge tag 'objtool-urgent-2025-12-06' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool fixes from Ingo Molnar: "Address various objtool scalability bugs/inefficiencies exposed by allmodconfig builds, plus improve the quality of alternatives instructions generated code and disassembly" * tag 'objtool-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool: Simplify .annotate_insn code generation output some more objtool: Add more robust signal error handling, detect and warn about stack overflows objtool: Remove newlines and tabs from annotation macros objtool: Consolidate annotation macros x86/asm: Remove ANNOTATE_DATA_SPECIAL usage x86/alternative: Remove ANNOTATE_DATA_SPECIAL usage objtool: Fix stack overflow in validate_branch()
2025-12-06Merge tag 'dma-mapping-6.19-2025-12-05' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux Pull dma-mapping updates from Marek Szyprowski: - More DMA mapping API refactoring to physical addresses as the primary interface instead of page+offset parameters. This time dma_map_ops callbacks are converted to physical addresses, what in turn results also in some simplification of architecture specific code (Leon Romanovsky and Jason Gunthorpe) - Clarify that dma_map_benchmark is not a kernel self-test, but standalone tool (Qinxin Xia) * tag 'dma-mapping-6.19-2025-12-05' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux: dma-mapping: remove unused map_page callback xen: swiotlb: Convert mapping routine to rely on physical address x86: Use physical address for DMA mapping sparc: Use physical address DMA mapping powerpc: Convert to physical address DMA mapping parisc: Convert DMA map_page to map_phys interface MIPS/jazzdma: Provide physical address directly alpha: Convert mapping routine to rely on physical address dma-mapping: remove unused mapping resource callbacks xen: swiotlb: Switch to physical address mapping callbacks ARM: dma-mapping: Switch to physical address mapping callbacks ARM: dma-mapping: Reduce struct page exposure in arch_sync_dma*() dma-mapping: convert dummy ops to physical address mapping dma-mapping: prepare dma_map_ops to conversion to physical address tools/dma: move dma_map_benchmark from selftests to tools/dma
2025-12-05Merge tag 'soc-drivers-6.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull SoC driver updates from Arnd Bergmann: "This is the first half of the driver changes: - A treewide interface change to the "syscore" operations for power management, as a preparation for future Tegra specific changes - Reset controller updates with added drivers for LAN969x, eic770 and RZ/G3S SoCs - Protection of system controller registers on Renesas and Google SoCs, to prevent trivially triggering a system crash from e.g. debugfs access - soc_device identification updates on Nvidia, Exynos and Mediatek - debugfs support in the ST STM32 firewall driver - Minor updates for SoC drivers on AMD/Xilinx, Renesas, Allwinner, TI - Cleanups for memory controller support on Nvidia and Renesas" * tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (114 commits) memory: tegra186-emc: Fix missing put_bpmp Documentation: reset: Remove reset_controller_add_lookup() reset: fix BIT macro reference reset: rzg2l-usbphy-ctrl: Fix a NULL vs IS_ERR() bug in probe reset: th1520: Support reset controllers in more subsystems reset: th1520: Prepare for supporting multiple controllers dt-bindings: reset: thead,th1520-reset: Add controllers for more subsys dt-bindings: reset: thead,th1520-reset: Remove non-VO-subsystem resets reset: remove legacy reset lookup code clk: davinci: psc: drop unused reset lookup reset: rzg2l-usbphy-ctrl: Add support for RZ/G3S SoC reset: rzg2l-usbphy-ctrl: Add support for USB PWRRDY dt-bindings: reset: renesas,rzg2l-usbphy-ctrl: Document RZ/G3S support reset: eswin: Add eic7700 reset driver dt-bindings: reset: eswin: Documentation for eic7700 SoC reset: sparx5: add LAN969x support dt-bindings: reset: microchip: Add LAN969x support soc: rockchip: grf: Add select correct PWM implementation on RK3368 soc/tegra: pmc: Add USB wake events for Tegra234 amba: tegra-ahb: Fix device leak on SMMU enable ...
2025-12-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "ARM: - Support for userspace handling of synchronous external aborts (SEAs), allowing the VMM to potentially handle the abort in a non-fatal manner - Large rework of the VGIC's list register handling with the goal of supporting more active/pending IRQs than available list registers in hardware. In addition, the VGIC now supports EOImode==1 style deactivations for IRQs which may occur on a separate vCPU than the one that acked the IRQ - Support for FEAT_XNX (user / privileged execute permissions) and FEAT_HAF (hardware update to the Access Flag) in the software page table walkers and shadow MMU - Allow page table destruction to reschedule, fixing long need_resched latencies observed when destroying a large VM - Minor fixes to KVM and selftests Loongarch: - Get VM PMU capability from HW GCFG register - Add AVEC basic support - Use 64-bit register definition for EIOINTC - Add KVM timer test cases for tools/selftests RISC/V: - SBI message passing (MPXY) support for KVM guest - Give a new, more specific error subcode for the case when in-kernel AIA virtualization fails to allocate IMSIC VS-file - Support KVM_DIRTY_LOG_INITIALLY_SET, enabling dirty log gradually in small chunks - Fix guest page fault within HLV* instructions - Flush VS-stage TLB after VCPU migration for Andes cores s390: - Always allocate ESCA (Extended System Control Area), instead of starting with the basic SCA and converting to ESCA with the addition of the 65th vCPU. The price is increased number of exits (and worse performance) on z10 and earlier processor; ESCA was introduced by z114/z196 in 2010 - VIRT_XFER_TO_GUEST_WORK support - Operation exception forwarding support - Cleanups x86: - Skip the costly "zap all SPTEs" on an MMIO generation wrap if MMIO SPTE caching is disabled, as there can't be any relevant SPTEs to zap - Relocate a misplaced export - Fix an async #PF bug where KVM would clear the completion queue when the guest transitioned in and out of paging mode, e.g. when handling an SMI and then returning to paged mode via RSM - Leave KVM's user-return notifier registered even when disabling virtualization, as long as kvm.ko is loaded. On reboot/shutdown, keeping the notifier registered is ok; the kernel does not use the MSRs and the callback will run cleanly and restore host MSRs if the CPU manages to return to userspace before the system goes down - Use the checked version of {get,put}_user() - Fix a long-lurking bug where KVM's lack of catch-up logic for periodic APIC timers can result in a hard lockup in the host - Revert the periodic kvmclock sync logic now that KVM doesn't use a clocksource that's subject to NTP corrections - Clean up KVM's handling of MMIO Stale Data and L1TF, and bury the latter behind CONFIG_CPU_MITIGATIONS - Context switch XCR0, XSS, and PKRU outside of the entry/exit fast path; the only reason they were handled in the fast path was to paper of a bug in the core #MC code, and that has long since been fixed - Add emulator support for AVX MOV instructions, to play nice with emulated devices whose guest drivers like to access PCI BARs with large multi-byte instructions x86 (AMD): - Fix a few missing "VMCB dirty" bugs - Fix the worst of KVM's lack of EFER.LMSLE emulation - Add AVIC support for addressing 4k vCPUs in x2AVIC mode - Fix incorrect handling of selective CR0 writes when checking intercepts during emulation of L2 instructions - Fix a currently-benign bug where KVM would clobber SPEC_CTRL[63:32] on VMRUN and #VMEXIT - Fix a bug where KVM corrupt the guest code stream when re-injecting a soft interrupt if the guest patched the underlying code after the VM-Exit, e.g. when Linux patches code with a temporary INT3 - Add KVM_X86_SNP_POLICY_BITS to advertise supported SNP policy bits to userspace, and extend KVM "support" to all policy bits that don't require any actual support from KVM x86 (Intel): - Use the root role from kvm_mmu_page to construct EPTPs instead of the current vCPU state, partly as worthwhile cleanup, but mostly to pave the way for tracking per-root TLB flushes, and elide EPT flushes on pCPU migration if the root is clean from a previous flush - Add a few missing nested consistency checks - Rip out support for doing "early" consistency checks via hardware as the functionality hasn't been used in years and is no longer useful in general; replace it with an off-by-default module param to WARN if hardware fails a check that KVM does not perform - Fix a currently-benign bug where KVM would drop the guest's SPEC_CTRL[63:32] on VM-Enter - Misc cleanups - Overhaul the TDX code to address systemic races where KVM (acting on behalf of userspace) could inadvertantly trigger lock contention in the TDX-Module; KVM was either working around these in weird, ugly ways, or was simply oblivious to them (though even Yan's devilish selftests could only break individual VMs, not the host kernel) - Fix a bug where KVM could corrupt a vCPU's cpu_list when freeing a TDX vCPU, if creating said vCPU failed partway through - Fix a few sparse warnings (bad annotation, 0 != NULL) - Use struct_size() to simplify copying TDX capabilities to userspace - Fix a bug where TDX would effectively corrupt user-return MSR values if the TDX Module rejects VP.ENTER and thus doesn't clobber host MSRs as expected Selftests: - Fix a math goof in mmu_stress_test when running on a single-CPU system/VM - Forcefully override ARCH from x86_64 to x86 to play nice with specifying ARCH=x86_64 on the command line - Extend a bunch of nested VMX to validate nested SVM as well - Add support for LA57 in the core VM_MODE_xxx macro, and add a test to verify KVM can save/restore nested VMX state when L1 is using 5-level paging, but L2 is not - Clean up the guest paging code in anticipation of sharing the core logic for nested EPT and nested NPT guest_memfd: - Add NUMA mempolicy support for guest_memfd, and clean up a variety of rough edges in guest_memfd along the way - Define a CLASS to automatically handle get+put when grabbing a guest_memfd from a memslot to make it harder to leak references - Enhance KVM selftests to make it easer to develop and debug selftests like those added for guest_memfd NUMA support, e.g. where test and/or KVM bugs often result in hard-to-debug SIGBUS errors - Misc cleanups Generic: - Use the recently-added WQ_PERCPU when creating the per-CPU workqueue for irqfd cleanup - Fix a goof in the dirty ring documentation - Fix choice of target for directed yield across different calls to kvm_vcpu_on_spin(); the function was always starting from the first vCPU instead of continuing the round-robin search" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (260 commits) KVM: arm64: at: Update AF on software walk only if VM has FEAT_HAFDBS KVM: arm64: at: Use correct HA bit in TCR_EL2 when regime is EL2 KVM: arm64: Document KVM_PGTABLE_PROT_{UX,PX} KVM: arm64: Fix spelling mistake "Unexpeced" -> "Unexpected" KVM: arm64: Add break to default case in kvm_pgtable_stage2_pte_prot() KVM: arm64: Add endian casting to kvm_swap_s[12]_desc() KVM: arm64: Fix compilation when CONFIG_ARM64_USE_LSE_ATOMICS=n KVM: arm64: selftests: Add test for AT emulation KVM: arm64: nv: Expose hardware access flag management to NV guests KVM: arm64: nv: Implement HW access flag management in stage-2 SW PTW KVM: arm64: Implement HW access flag management in stage-1 SW PTW KVM: arm64: Propagate PTW errors up to AT emulation KVM: arm64: Add helper for swapping guest descriptor KVM: arm64: nv: Use pgtable definitions in stage-2 walk KVM: arm64: Handle endianness in read helper for emulated PTW KVM: arm64: nv: Stop passing vCPU through void ptr in S2 PTW KVM: arm64: Call helper for reading descriptors directly KVM: arm64: nv: Advertise support for FEAT_XNX KVM: arm64: Teach ptdump about FEAT_XNX permissions KVM: s390: Use generic VIRT_XFER_TO_GUEST_WORK functions ...
2025-12-05mshv: Cleanly shutdown root partition with MSHVPraveen K Paladugu
Root partitions running on MSHV currently attempt ACPI power-off, which MSHV intercepts and triggers a Machine Check Exception (MCE), leading to a kernel panic. Root partitions panic with a trace similar to: [ 81.306348] reboot: Power down [ 81.314709] mce: [Hardware Error]: CPU 0: Machine Check Exception: 4 Bank 0: b2000000c0060001 [ 81.314711] mce: [Hardware Error]: TSC 3b8cb60a66 PPIN 11d98332458e4ea9 [ 81.314713] mce: [Hardware Error]: PROCESSOR 0:606a6 TIME 1759339405 SOCKET 0 APIC 0 microcode ffffffff [ 81.314715] mce: [Hardware Error]: Run the above through 'mcelog --ascii' [ 81.314716] mce: [Hardware Error]: Machine check: Processor context corrupt [ 81.314717] Kernel panic - not syncing: Fatal machine check To avoid this, configure the sleep state in the hypervisor and invoke the HVCALL_ENTER_SLEEP_STATE hypercall as the final step in the shutdown sequence. This ensures a clean and safe shutdown of the root partition. Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com> Co-developed-by: Anatol Belski <anbelski@linux.microsoft.com> Signed-off-by: Anatol Belski <anbelski@linux.microsoft.com> Reviewed-by: Easwar Hariharan <easwar.hariharan@linux.microsoft.com> Acked-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
2025-12-05Merge tag 'mm-stable-2025-12-03-21-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki) Rework the vmalloc() code to support non-blocking allocations (GFP_ATOIC, GFP_NOWAIT) "ksm: fix exec/fork inheritance" (xu xin) Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited across fork/exec "mm/zswap: misc cleanup of code and documentations" (SeongJae Park) Some light maintenance work on the zswap code "mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira) Enhance the /sys/kernel/debug/page_owner debug feature by adding unique identifiers to differentiate the various stack traces so that userspace monitoring tools can better match stack traces over time "mm/page_alloc: pcp->batch cleanups" (Joshua Hahn) Minor alterations to the page allocator's per-cpu-pages feature "Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra) Address a scalability issue in userfaultfd's UFFDIO_MOVE operation "kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov) "drivers/base/node: fold node register and unregister functions" (Donet Tom) Clean up the NUMA node handling code a little "mm: some optimizations for prot numa" (Kefeng Wang) Cleanups and small optimizations to the NUMA allocation hinting code "mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn) Address long lock hold times at boot on large machines. These were causing (harmless) softlockup warnings "optimize the logic for handling dirty file folios during reclaim" (Baolin Wang) Remove some now-unnecessary work from page reclaim "mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park) Enhance the DAMOS auto-tuning feature "mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan) Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace configuration "expand mmap_prepare functionality, port more users" (Lorenzo Stoakes) Enhance the new(ish) file_operations.mmap_prepare() method and port additional callsites from the old ->mmap() over to ->mmap_prepare() "Fix stale IOTLB entries for kernel address space" (Lu Baolu) Fix a bug (and possible security issue on non-x86) in the IOMMU code. In some situations the IOMMU could be left hanging onto a stale kernel pagetable entry "mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang) Clean up and optimize the folio splitting code "mm, swap: misc cleanup and bugfix" (Kairui Song) Some cleanups and a minor fix in the swap discard code "mm/damon: misc documentation fixups" (SeongJae Park) "mm/damon: support pin-point targets removal" (SeongJae Park) Permit userspace to remove a specific monitoring target in the middle of the current targets list "mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo) A couple of cleanups related to mm header file inclusion "mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He) improve the selection of swap devices for NUMA machines "mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista) Change the memory block labels from macros to enums so they will appear in kernel debug info "ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes) Address an inefficiency when KSM unmerges an address range "mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park) Fix leaks and unhandled malloc() failures in DAMON userspace unit tests "some cleanups for pageout()" (Baolin Wang) Clean up a couple of minor things in the page scanner's writeback-for-eviction code "mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu) Move hugetlb's sysfs/sysctl handling code into a new file "introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes) Make the VMA guard regions available in /proc/pid/smaps and improves the mergeability of guarded VMAs "mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes) Reduce mmap lock contention for callers performing VMA guard region operations "vma_start_write_killable" (Matthew Wilcox) Start work on permitting applications to be killed when they are waiting on a read_lock on the VMA lock "mm/damon/tests: add more tests for online parameters commit" (SeongJae Park) Add additional userspace testing of DAMON's "commit" feature "mm/damon: misc cleanups" (SeongJae Park) "make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes) Address the possible loss of a VMA's VM_SOFTDIRTY flag when that VMA is merged with another "mm: support device-private THP" (Balbir Singh) Introduce support for Transparent Huge Page (THP) migration in zone device-private memory "Optimize folio split in memory failure" (Zi Yan) "mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang) Some more cleanups in the folio splitting code "mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes) Clean up our handling of pagetable leaf entries by introducing the concept of 'software leaf entries', of type softleaf_t "reparent the THP split queue" (Muchun Song) Reparent the THP split queue to its parent memcg. This is in preparation for addressing the long-standing "dying memcg" problem, wherein dead memcg's linger for too long, consuming memory resources "unify PMD scan results and remove redundant cleanup" (Wei Yang) A little cleanup in the hugepage collapse code "zram: introduce writeback bio batching" (Sergey Senozhatsky) Improve zram writeback efficiency by introducing batched bio writeback support "memcg: cleanup the memcg stats interfaces" (Shakeel Butt) Clean up our handling of the interrupt safety of some memcg stats "make vmalloc gfp flags usage more apparent" (Vishal Moola) Clean up vmalloc's handling of incoming GFP flags "mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang) Teach soft dirty and userfaultfd write protect tracking to use RISC-V's Svrsw60t59b extension "mm: swap: small fixes and comment cleanups" (Youngjun Park) Fix a small bug and clean up some of the swap code "initial work on making VMA flags a bitmap" (Lorenzo Stoakes) Start work on converting the vma struct's flags to a bitmap, so we stop running out of them, especially on 32-bit "mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park) Address a possible bug in the swap discard code and clean things up a little [ This merge also reverts commit ebb9aeb980e5 ("vfio/nvgrace-gpu: register device memory for poison handling") because it looks broken to me, I've asked for clarification - Linus ] * tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) mm: fix vma_start_write_killable() signal handling mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate mm/swapfile: fix list iteration when next node is removed during discard fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling mm/kfence: add reboot notifier to disable KFENCE on shutdown memcg: remove inc/dec_lruvec_kmem_state helpers selftests/mm/uffd: initialize char variable to Null mm: fix DEBUG_RODATA_TEST indentation in Kconfig mm: introduce VMA flags bitmap type tools/testing/vma: eliminate dependency on vma->__vm_flags mm: simplify and rename mm flags function for clarity mm: declare VMA flags by bit zram: fix a spelling mistake mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity mm/vmscan: skip increasing kswapd_failures when reclaim was boosted pagemap: update BUDDY flag documentation mm: swap: remove scan_swap_map_slots() references from comments mm: swap: change swap_alloc_slow() to void mm, swap: remove redundant comment for read_swap_cache_async mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational ...
2025-12-03Merge tag 'bpf-next-6.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Pull bpf updates from Alexei Starovoitov: - Convert selftests/bpf/test_tc_edt and test_tc_tunnel from .sh to test_progs runner (Alexis Lothoré) - Convert selftests/bpf/test_xsk to test_progs runner (Bastien Curutchet) - Replace bpf memory allocator with kmalloc_nolock() in bpf_local_storage (Amery Hung), and in bpf streams and range tree (Puranjay Mohan) - Introduce support for indirect jumps in BPF verifier and x86 JIT (Anton Protopopov) and arm64 JIT (Puranjay Mohan) - Remove runqslower bpf tool (Hoyeon Lee) - Fix corner cases in the verifier to close several syzbot reports (Eduard Zingerman, KaFai Wan) - Several improvements in deadlock detection in rqspinlock (Kumar Kartikeya Dwivedi) - Implement "jmp" mode for BPF trampoline and corresponding DYNAMIC_FTRACE_WITH_JMP. It improves "fexit" program type performance from 80 M/s to 136 M/s. With Steven's Ack. (Menglong Dong) - Add ability to test non-linear skbs in BPF_PROG_TEST_RUN (Paul Chaignon) - Do not let BPF_PROG_TEST_RUN emit invalid GSO types to stack (Daniel Borkmann) - Generalize buildid reader into bpf_dynptr (Mykyta Yatsenko) - Optimize bpf_map_update_elem() for map-in-map types (Ritesh Oedayrajsingh Varma) - Introduce overwrite mode for BPF ring buffer (Xu Kuohai) * tag 'bpf-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (169 commits) bpf: optimize bpf_map_update_elem() for map-in-map types bpf: make kprobe_multi_link_prog_run always_inline selftests/bpf: do not hardcode target rate in test_tc_edt BPF program selftests/bpf: remove test_tc_edt.sh selftests/bpf: integrate test_tc_edt into test_progs selftests/bpf: rename test_tc_edt.bpf.c section to expose program type selftests/bpf: Add success stats to rqspinlock stress test rqspinlock: Precede non-head waiter queueing with AA check rqspinlock: Disable spinning for trylock fallback rqspinlock: Use trylock fallback when per-CPU rqnode is busy rqspinlock: Perform AA checks immediately rqspinlock: Enclose lock/unlock within lock entry acquisitions bpf: Remove runqslower tool selftests/bpf: Remove usage of lsm/file_alloc_security in selftest bpf: Disable file_alloc_security hook bpf: check for insn arrays in check_ptr_alignment bpf: force BPF_F_RDONLY_PROG on insn array creation bpf: Fix exclusive map memory leak selftests/bpf: Make CS length configurable for rqspinlock stress test selftests/bpf: Add lock wait time stats to rqspinlock stress test ...
2025-12-03objtool: Remove newlines and tabs from annotation macrosJosh Poimboeuf
Remove newlines and tabs from the annotation macros so the invoking code can insert them as needed to match the style of the surrounding code. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://patch.msgid.link/66305834c2eb78f082217611b756231ae9c0b555.1764694625.git.jpoimboe@kernel.org
2025-12-03x86/asm: Remove ANNOTATE_DATA_SPECIAL usageJosh Poimboeuf
Instead of manually annotating each __ex_table entry, just make the section mergeable and store the entry size in the ELF section header. Either way works for objtool create_fake_symbols(), this way produces cleaner code generation. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://patch.msgid.link/b858cb7891c1ba0080e22a9c32595e6c302435e2.1764694625.git.jpoimboe@kernel.org
2025-12-03x86/alternative: Remove ANNOTATE_DATA_SPECIAL usageJosh Poimboeuf
Instead of manually annotating each .altinstructions entry, just make the section mergeable and store the entry size in the ELF section header. Either way works for objtool create_fake_symbols(), this way produces cleaner code generation. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://patch.msgid.link/5ac04e6db5be6453dce8003a771ebb0c47b4cd7a.1764694625.git.jpoimboe@kernel.org
2025-12-02Merge tag 'x86_cpu_for_6.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 CPU feature updates from Dave Hansen: "The biggest thing of note here is Linear Address Space Separation (LASS). It represents the first time I can think of that the upper=>kernel/lower=>user address space convention is actually recognized by the hardware on x86. It ensures that userspace can not even get the hardware to _start_ page walks for the kernel address space. This, of course, is a really nice generic side channel defense. This is really only a down payment on LASS support. There are still some details to work out in its interaction with EFI calls and vsyscall emulation. For now, LASS is disabled if either of those features is compiled in (which is almost always the case). There's also one straggler commit in here which converts an under-utilized AMD CPU feature leaf into a generic Linux-defined leaf so more feature can be packed in there. Summary: - Enable Linear Address Space Separation (LASS) - Change X86_FEATURE leaf 17 from an AMD leaf to Linux-defined" * tag 'x86_cpu_for_6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Enable LASS during CPU initialization selftests/x86: Update the negative vsyscall tests to expect a #GP x86/traps: Communicate a LASS violation in #GP message x86/kexec: Disable LASS during relocate kernel x86/alternatives: Disable LASS when patching kernel code x86/asm: Introduce inline memcpy and memset x86/cpu: Add an LASS dependency on SMAP x86/cpufeatures: Enumerate the LASS feature bits x86/cpufeatures: Make X86_FEATURE leaf 17 Linux-specific
2025-12-02Merge tag 'x86_misc_for_6.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull misc x86 updates from Dave Hansen: "The most significant are some changes to ensure that symbols exported for KVM are used only by KVM modules themselves, along with some related cleanups. In true x86/misc fashion, the other patch is completely unrelated and just enhances an existing pr_warn() to make it clear to users how they have tainted their kernel when something is mucking with MSRs. Summary: - Make MSR-induced taint easier for users to track down - Restrict KVM-specific exports to KVM itself" * tag 'x86_misc_for_6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Restrict KVM-induced symbol exports to KVM modules where obvious/possible x86/mm: Drop unnecessary export of "ptdump_walk_pgd_level_debugfs" x86/mtrr: Drop unnecessary export of "mtrr_state" x86/bugs: Drop unnecessary export of "x86_spec_ctrl_base" x86/msr: Add CPU_OUT_OF_SPEC taint name to "unrecognized" pr_warn(msg)
2025-12-02Merge tag 'x86_sgx_for_6.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SGX updates from Dave HansenL "The main content here is adding support for the new EUPDATESVN SGX ISA. Before this, folks who updated microcode had to reboot before enclaves could attest to the new microcode. The new functionality lets them do this without a reboot. The rest are some nice, but relatively mundane comment and kernel-doc fixups. Summary: - Allow security version (SVN) updates so enclaves can attest to new microcode - Fix kernel docs typos" * tag 'x86_sgx_for_6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sgx: Fix a typo in the kernel-doc comment for enum sgx_attribute x86/sgx: Remove superfluous asterisk from copyright comment in asm/sgx.h x86/sgx: Document structs and enums with '@', not '%' x86/sgx: Add kernel-doc descriptions for params passed to vDSO user handler x86/sgx: Add a missing colon in kernel-doc markup for "struct sgx_enclave_run" x86/sgx: Enable automatic SVN updates for SGX enclaves x86/sgx: Implement ENCLS[EUPDATESVN] x86/sgx: Define error codes for use by ENCLS[EUPDATESVN] x86/cpufeatures: Add X86_FEATURE_SGX_EUPDATESVN feature flag x86/sgx: Introduce functions to count the sgx_(vepc_)open()
2025-12-02Merge tag 'x86_bugs_for_v6.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 CPU mitigation updates from Borislav Petkov: - Convert the tsx= cmdline parsing to use early_param() - Cleanup forward declarations gunk in bugs.c * tag 'x86_bugs_for_v6.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bugs: Get rid of the forward declarations x86/tsx: Get the tsx= command line parameter with early_param() x86/tsx: Make tsx_ctrl_state static
2025-12-02Merge tag 'x86_cleanups_for_v6.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cleanups from Borislav Petkov: - The mandatory pile of cleanups the cat drags in every merge window * tag 'x86_cleanups_for_v6.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Clean up whitespace in a20.c x86/mm: Delete disabled debug code x86/{boot,mtrr}: Remove unused function declarations x86/percpu: Use BIT_WORD() and BIT_MASK() macros x86/cpufeatures: Correct LKGS feature flag description x86/idtentry: Add missing '*' to kernel-doc lines
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
2025-12-02Merge tag 'x86_microcode_for_v6.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loading updates from Borislav Petkov: - Add microcode staging support on Intel: it moves the sole microcode blobs loading to a non-critical path so that microcode loading latencies are kept at minimum. The actual "directing" the hardware to load microcode is the only step which is done on the critical path. This scheme is also opportunistic as in: on a failure, the machinery falls back to normal loading - Add the capability to the AMD side of the loader to select one of two per-family/model/stepping patches: one is pre-Entrysign and the other is post-Entrysign; with the goal to take care of machines which haven't updated their BIOS yet - something they should absolutely do as this is the only proper Entrysign fix - Other small cleanups and fixlets * tag 'x86_microcode_for_v6.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode: Mark early_parse_cmdline() as __init x86/microcode/AMD: Select which microcode patch to load x86/microcode/intel: Enable staging when available x86/microcode/intel: Support mailbox transfer x86/microcode/intel: Implement staging handler x86/microcode/intel: Define staging state struct x86/microcode/intel: Establish staging control logic x86/microcode: Introduce staging step to reduce late-loading time x86/cpu/topology: Make primary thread mask available with SMP=n
2025-12-02Merge tag 'ras_core_for_v6.19_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RAS updates from Borislav Petkov: - The second part of the AMD MCA interrupts rework after the last-minute show-stopper from the last merge window was sorted out. After this, the AMD MCA deferred errors, thresholding and corrected errors interrupt handlers use common MCA code and are tightly integrated into the core MCA code, thereby getting rid of considerable duplication. All culminating into allowing CMCI error thresholding storms to be detected at AMD too, using the common infrastructure - Add support for two new MCA bank bits on AMD Zen6 which denote whether the error address logged is a system physical address, which obviates the need for it to be translated before further error recovery can be done * tag 'ras_core_for_v6.19_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mce: Handle AMD threshold interrupt storms x86/mce: Do not clear bank's poll bit in mce_poll_banks on AMD SMCA systems x86/mce: Add support for physical address valid bit x86/mce: Save and use APEI corrected threshold limit x86/mce/amd: Define threshold restart function for banks x86/mce/amd: Remove redundant reset_block() x86/mce/amd: Support SMCA Corrected Error Interrupt x86/mce/amd: Enable interrupt vectors once per-CPU on SMCA systems x86/mce: Unify AMD DFR handler with MCA Polling x86/mce: Unify AMD THR handler with MCA Polling
2025-12-01Merge tag 'core-bugs-2025-12-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull bug handling infrastructure updates from Ingo Molnar: "Core updates: - Improve WARN(), which has vararg printf like arguments, to work with the x86 #UD based WARN-optimizing infrastructure by hiding the format in the bug_table and replacing this first argument with the address of the bug-table entry, while making the actual function that's called a UD1 instruction (Peter Zijlstra) - Introduce the CONFIG_DEBUG_BUGVERBOSE_DETAILED Kconfig switch (Ingo Molnar, s390 support by Heiko Carstens) Fixes and cleanups: - bugs/s390: Remove private WARN_ON() implementation (Heiko Carstens) - <asm/bugs.h>: Make i386 use GENERIC_BUG_RELATIVE_POINTERS (Peter Zijlstra)" * tag 'core-bugs-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits) x86/bugs: Make i386 use GENERIC_BUG_RELATIVE_POINTERS x86/bug: Fix BUG_FORMAT vs KASLR x86_64/bug: Inline the UD1 x86/bug: Implement WARN_ONCE() x86_64/bug: Implement __WARN_printf() x86/bug: Use BUG_FORMAT for DEBUG_BUGVERBOSE_DETAILED x86/bug: Add BUG_FORMAT basics bug: Allow architectures to provide __WARN_printf() bug: Implement WARN_ON() using __WARN_FLAGS() bug: Add report_bug_entry() bug: Add BUG_FORMAT_ARGS infrastructure bug: Clean up CONFIG_GENERIC_BUG_RELATIVE_POINTERS bug: Add BUG_FORMAT infrastructure x86: Rework __bug_table helpers bugs/s390: Remove private WARN_ON() implementation bugs/core: Reorganize fields in the first line of WARNING output, add ->comm[] output bugs/sh: Concatenate 'cond_str' with '__FILE__' in __WARN_FLAGS(), to extend WARN_ON/BUG_ON output bugs/parisc: Concatenate 'cond_str' with '__FILE__' in __WARN_FLAGS(), to extend WARN_ON/BUG_ON output bugs/riscv: Concatenate 'cond_str' with '__FILE__' in __BUG_FLAGS(), to extend WARN_ON/BUG_ON output bugs/riscv: Pass in 'cond_str' to __BUG_FLAGS() ...
2025-12-01Merge tag 'x86-core-2025-12-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Ingo Molnar: - x86/alternatives: Drop unnecessary test after call to alt_replace_call() (Juergen Gross) - x86/dumpstack: Prevent KASAN false positive warnings in __show_regs() (Tengda Wu) * tag 'x86-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/dumpstack: Prevent KASAN false positive warnings in __show_regs() x86/alternative: Drop not needed test after call of alt_replace_call()
2025-12-01Merge tag 'x86-apic-2025-12-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Ingo Molnar: - x86/apic: Fix the frequency in apic=verbose log output (Julian Stecklina) - Simplify mp_irqdomain_alloc() slightly (Christophe JAILLET) * tag 'x86-apic-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Fix frequency in apic=verbose log output x86/ioapic: Simplify mp_irqdomain_alloc() slightly
2025-12-01Merge tag 'sched-core-2025-12-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Scalability and load-balancing improvements: - Enable scheduler feature NEXT_BUDDY (Mel Gorman) - Reimplement NEXT_BUDDY to align with EEVDF goals (Mel Gorman) - Skip sched_balance_running cmpxchg when balance is not due (Tim Chen) - Implement generic code for architecture specific sched domain NUMA distances (Tim Chen) - Optimize the NUMA distances of the sched-domains builds of Intel Granite Rapids (GNR) and Clearwater Forest (CWF) platforms (Tim Chen) - Implement proportional newidle balance: a randomized algorithm that runs newidle balancing proportional to its success rate. (Peter Zijlstra) Scheduler infrastructure changes: - Implement the 'sched_change' scoped_guard() pattern for the entire scheduler (Peter Zijlstra) - More broadly utilize the sched_change guard (Peter Zijlstra) - Add support to pick functions to take runqueue-flags (Joel Fernandes) - Provide and use set_need_resched_current() (Peter Zijlstra) Fair scheduling enhancements: - Forfeit vruntime on yield (Fernand Sieber) - Only update stats for allowed CPUs when looking for dst group (Adam Li) CPU-core scheduling enhancements: - Optimize core cookie matching check (Fernand Sieber) Deadline scheduler fixes: - Only set free_cpus for online runqueues (Doug Berger) - Fix dl_server time accounting (Peter Zijlstra) - Fix dl_server stop condition (Peter Zijlstra) Proxy scheduling fixes: - Yield the donor task (Fernand Sieber) Fixes and cleanups: - Fix do_set_cpus_allowed() locking (Peter Zijlstra) - Fix migrate_disable_switch() locking (Peter Zijlstra) - Remove double update_rq_clock() in __set_cpus_allowed_ptr_locked() (Hao Jia) - Increase sched_tick_remote timeout (Phil Auld) - sched/deadline: Use cpumask_weight_and() in dl_bw_cpus() (Shrikanth Hegde) - sched/deadline: Clean up select_task_rq_dl() (Shrikanth Hegde)" * tag 'sched-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits) sched: Provide and use set_need_resched_current() sched/fair: Proportional newidle balance sched/fair: Small cleanup to update_newidle_cost() sched/fair: Small cleanup to sched_balance_newidle() sched/fair: Revert max_newidle_lb_cost bump sched/fair: Reimplement NEXT_BUDDY to align with EEVDF goals sched/fair: Enable scheduler feature NEXT_BUDDY sched: Increase sched_tick_remote timeout sched/fair: Have SD_SERIALIZE affect newidle balancing sched/fair: Skip sched_balance_running cmpxchg when balance is not due sched/deadline: Minor cleanup in select_task_rq_dl() sched/deadline: Use cpumask_weight_and() in dl_bw_cpus sched/deadline: Document dl_server sched/deadline: Fix dl_server stop condition sched/deadline: Fix dl_server time accounting sched/core: Remove double update_rq_clock() in __set_cpus_allowed_ptr_locked() sched/eevdf: Fix min_vruntime vs avg_vruntime sched/core: Add comment explaining force-idle vruntime snapshots sched/core: Optimize core cookie matching check sched/proxy: Yield the donor task ...
2025-12-01Merge tag 'perf-core-2025-12-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull performance events updates from Ingo Molnar: "Callchain support: - Add support for deferred user-space stack unwinding for perf, enabled on x86. (Peter Zijlstra, Steven Rostedt) - unwind_user/x86: Enable frame pointer unwinding on x86 (Josh Poimboeuf) x86 PMU support and infrastructure: - x86/insn: Simplify for_each_insn_prefix() (Peter Zijlstra) - x86/insn,uprobes,alternative: Unify insn_is_nop() (Peter Zijlstra) Intel PMU driver: - Large series to prepare for and implement architectural PEBS support for Intel platforms such as Clearwater Forest (CWF) and Panther Lake (PTL). (Dapeng Mi, Kan Liang) - Check dynamic constraints (Kan Liang) - Optimize PEBS extended config (Peter Zijlstra) - cstates: - Remove PC3 support from LunarLake (Zhang Rui) - Add Pantherlake support (Zhang Rui) - Clearwater Forest support (Zide Chen) AMD PMU driver: - x86/amd: Check event before enable to avoid GPF (George Kennedy) Fixes and cleanups: - task_work: Fix NMI race condition (Peter Zijlstra) - perf/x86: Fix NULL event access and potential PEBS record loss (Dapeng Mi) - Misc other fixes and cleanups (Dapeng Mi, Ingo Molnar, Peter Zijlstra)" * tag 'perf-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) perf/x86/intel: Fix and clean up intel_pmu_drain_arch_pebs() type use perf/x86/intel: Optimize PEBS extended config perf/x86/intel: Check PEBS dyn_constraints perf/x86/intel: Add a check for dynamic constraints perf/x86/intel: Add counter group support for arch-PEBS perf/x86/intel: Setup PEBS data configuration and enable legacy groups perf/x86/intel: Update dyn_constraint base on PEBS event precise level perf/x86/intel: Allocate arch-PEBS buffer and initialize PEBS_BASE MSR perf/x86/intel: Process arch-PEBS records or record fragments perf/x86/intel/ds: Factor out PEBS group processing code to functions perf/x86/intel/ds: Factor out PEBS record processing code to functions perf/x86/intel: Initialize architectural PEBS perf/x86/intel: Correct large PEBS flag check perf/x86/intel: Replace x86_pmu.drain_pebs calling with static call perf/x86: Fix NULL event access and potential PEBS record loss perf/x86: Remove redundant is_x86_event() prototype entry,unwind/deferred: Fix unwind_reset_info() placement unwind_user/x86: Fix arch=um build perf: Support deferred user unwind unwind_user/x86: Teach FP unwind about start of function ...
2025-12-01Merge tag 'objtool-core-2025-12-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool updates from Ingo Molnar: - klp-build livepatch module generation (Josh Poimboeuf) Introduce new objtool features and a klp-build script to generate livepatch modules using a source .patch as input. This builds on concepts from the longstanding out-of-tree kpatch project which began in 2012 and has been used for many years to generate livepatch modules for production kernels. However, this is a complete rewrite which incorporates hard-earned lessons from 12+ years of maintaining kpatch. Key improvements compared to kpatch-build: - Integrated with objtool: Leverages objtool's existing control-flow graph analysis to help detect changed functions. - Works on vmlinux.o: Supports late-linked objects, making it compatible with LTO, IBT, and similar. - Simplified code base: ~3k fewer lines of code. - Upstream: No more out-of-tree #ifdef hacks, far less cruft. - Cleaner internals: Vastly simplified logic for symbol/section/reloc inclusion and special section extraction. - Robust __LINE__ macro handling: Avoids false positive binary diffs caused by the __LINE__ macro by introducing a fix-patch-lines script which injects #line directives into the source .patch to preserve the original line numbers at compile time. - Disassemble code with libopcodes instead of running objdump (Alexandre Chartre) - Disassemble support (-d option to objtool) by Alexandre Chartre, which supports the decoding of various Linux kernel code generation specials such as alternatives: 17ef: sched_balance_find_dst_group+0x62f mov 0x34(%r9),%edx 17f3: sched_balance_find_dst_group+0x633 | <alternative.17f3> | X86_FEATURE_POPCNT 17f3: sched_balance_find_dst_group+0x633 | call 0x17f8 <__sw_hweight64> | popcnt %rdi,%rax 17f8: sched_balance_find_dst_group+0x638 cmp %eax,%edx ... jump table alternatives: 1895: sched_use_asym_prio+0x5 test $0x8,%ch 1898: sched_use_asym_prio+0x8 je 0x18a9 <sched_use_asym_prio+0x19> 189a: sched_use_asym_prio+0xa | <jump_table.189a> | JUMP 189a: sched_use_asym_prio+0xa | jmp 0x18ae <sched_use_asym_prio+0x1e> | nop2 189c: sched_use_asym_prio+0xc mov $0x1,%eax 18a1: sched_use_asym_prio+0x11 and $0x80,%ecx ... exception table alternatives: native_read_msr: 5b80: native_read_msr+0x0 mov %edi,%ecx 5b82: native_read_msr+0x2 | <ex_table.5b82> | EXCEPTION 5b82: native_read_msr+0x2 | rdmsr | resume at 0x5b84 <native_read_msr+0x4> 5b84: native_read_msr+0x4 shl $0x20,%rdx .... x86 feature flag decoding (also see the X86_FEATURE_POPCNT example in sched_balance_find_dst_group() above): 2faaf: start_thread_common.constprop.0+0x1f jne 0x2fba4 <start_thread_common.constprop.0+0x114> 2fab5: start_thread_common.constprop.0+0x25 | <alternative.2fab5> | X86_FEATURE_ALWAYS | X86_BUG_NULL_SEG 2fab5: start_thread_common.constprop.0+0x25 | jmp 0x2faba <.altinstr_aux+0x2f4> | jmp 0x4b0 <start_thread_common.constprop.0+0x3f> | nop5 2faba: start_thread_common.constprop.0+0x2a mov $0x2b,%eax ... NOP sequence shortening: 1048e2: snapshot_write_finalize+0xc2 je 0x104917 <snapshot_write_finalize+0xf7> 1048e4: snapshot_write_finalize+0xc4 nop6 1048ea: snapshot_write_finalize+0xca nop11 1048f5: snapshot_write_finalize+0xd5 nop11 104900: snapshot_write_finalize+0xe0 mov %rax,%rcx 104903: snapshot_write_finalize+0xe3 mov 0x10(%rdx),%rax ... and much more. - Function validation tracing support (Alexandre Chartre) - Various -ffunction-sections fixes (Josh Poimboeuf) - Clang AutoFDO (Automated Feedback-Directed Optimizations) support (Josh Poimboeuf) - Misc fixes and cleanups (Borislav Petkov, Chen Ni, Dylan Hatch, Ingo Molnar, John Wang, Josh Poimboeuf, Pankaj Raghav, Peter Zijlstra, Thorsten Blum) * tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits) objtool: Fix segfault on unknown alternatives objtool: Build with disassembly can fail when including bdf.h objtool: Trim trailing NOPs in alternative objtool: Add wide output for disassembly objtool: Compact output for alternatives with one instruction objtool: Improve naming of group alternatives objtool: Add Function to get the name of a CPU feature objtool: Provide access to feature and flags of group alternatives objtool: Fix address references in alternatives objtool: Disassemble jump table alternatives objtool: Disassemble exception table alternatives objtool: Print addresses with alternative instructions objtool: Disassemble group alternatives objtool: Print headers for alternatives objtool: Preserve alternatives order objtool: Add the --disas=<function-pattern> action objtool: Do not validate IBT for .return_sites and .call_sites objtool: Improve tracing of alternative instructions objtool: Add functions to better name alternatives objtool: Identify the different types of alternatives ...
2025-11-27vmcoreinfo: track and log recoverable hardware errorsBreno Leitao
Introduce a generic infrastructure for tracking recoverable hardware errors (HW errors that are visible to the OS but does not cause a panic) and record them for vmcore consumption. This aids post-mortem crash analysis tools by preserving a count and timestamp for the last occurrence of such errors. On the other side, correctable errors, which the OS typically remains unaware of because the underlying hardware handles them transparently, are less relevant for crash dump and therefore are NOT tracked in this infrastructure. Add centralized logging for sources of recoverable hardware errors based on the subsystem it has been notified. hwerror_data is write-only at kernel runtime, and it is meant to be read from vmcore using tools like crash/drgn. For example, this is how it looks like when opening the crashdump from drgn. >>> prog['hwerror_data'] (struct hwerror_info[1]){ { .count = (int)844, .timestamp = (time64_t)1752852018, }, ... This helps fleet operators quickly triage whether a crash may be influenced by hardware recoverable errors (which executes a uncommon code path in the kernel), especially when recoverable errors occurred shortly before a panic, such as the bug fixed by commit ee62ce7a1d90 ("page_pool: Track DMA-mapped pages and unmap them when destroying the pool") This is not intended to replace full hardware diagnostics but provides a fast way to correlate hardware events with kernel panics quickly. Rare machine check exceptions—like those indicated by mce_flags.p5 or mce_flags.winchip—are not accounted for in this method, as they fall outside the intended usage scope for this feature's user base. [leitao@debian.org: add hw-recoverable-errors to toctree] Link: https://lkml.kernel.org/r/20251127-vmcoreinfo_fix-v1-1-26f5b1c43da9@debian.org Link: https://lkml.kernel.org/r/20251010-vmcore_hw_error-v5-1-636ede3efe44@debian.org Signed-off-by: Breno Leitao <leitao@debian.org> Suggested-by: Tony Luck <tony.luck@intel.com> Suggested-by: Shuai Xue <xueshuai@linux.alibaba.com> Reviewed-by: Shuai Xue <xueshuai@linux.alibaba.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> [APEI] Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Bob Moore <robert.moore@intel.com> Cc: Borislav Betkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morse <james.morse@arm.com> Cc: Konrad Rzessutek Wilk <konrad.wilk@oracle.com> Cc: Len Brown <lenb@kernel.org> Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Omar Sandoval <osandov@osandov.com> Cc: Thomas Gleinxer <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-26Merge tag 'kvm-x86-svm-6.19' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM SVM changes for 6.19: - Fix a few missing "VMCB dirty" bugs. - Fix the worst of KVM's lack of EFER.LMSLE emulation. - Add AVIC support for addressing 4k vCPUs in x2AVIC mode. - Fix incorrect handling of selective CR0 writes when checking intercepts during emulation of L2 instructions. - Fix a currently-benign bug where KVM would clobber SPEC_CTRL[63:32] on VMRUN and #VMEXIT. - Fix a bug where KVM corrupt the guest code stream when re-injecting a soft interrupt if the guest patched the underlying code after the VM-Exit, e.g. when Linux patches code with a temporary INT3. - Add KVM_X86_SNP_POLICY_BITS to advertise supported SNP policy bits to userspace, and extend KVM "support" to all policy bits that don't require any actual support from KVM.
2025-11-26Merge tag 'kvm-x86-misc-6.19' of https://github.com/kvm-x86/linux into HEADPaolo Bonzini
KVM x86 misc changes for 6.19: - Fix an async #PF bug where KVM would clear the completion queue when the guest transitioned in and out of paging mode, e.g. when handling an SMI and then returning to paged mode via RSM. - Fix a bug where TDX would effectively corrupt user-return MSR values if the TDX Module rejects VP.ENTER and thus doesn't clobber host MSRs as expected. - Leave the user-return notifier used to restore MSRs registered when disabling virtualization, and instead pin kvm.ko. Restoring host MSRs via IPI callback is either pointless (clean reboot) or dangerous (forced reboot) since KVM has no idea what code it's interrupting. - Use the checked version of {get,put}_user(), as Linus wants to kill them off, and they're measurably faster on modern CPUs due to the unchecked versions containing an LFENCE. - Fix a long-lurking bug where KVM's lack of catch-up logic for periodic APIC timers can result in a hard lockup in the host. - Revert the periodic kvmclock sync logic now that KVM doesn't use a clocksource that's subject to NPT corrections. - Clean up KVM's handling of MMIO Stale Data and L1TF, and bury the latter behind CONFIG_CPU_MITIGATIONS. - Context switch XCR0, XSS, and PKRU outside of the entry/exit fastpath as the only reason they were handled in the faspath was to paper of a bug in the core #MC code that has long since been fixed. - Add emulator support for AVX MOV instructions to play nice with emulated devices whose PCI BARs guest drivers like to access with large multi-byte instructions.
2025-11-24x86_64/bug: Inline the UD1Peter Zijlstra
(Ab)use the static_call infrastructure to convert all: call __WARN_trap instances into the desired: ud1 (%edx), %rdi eliminating the CALL/RET, but more importantly, fixing the fact that all WARNs will have: RIP: 0010:__WARN_trap+0 Basically, by making it a static_call trampoline call, objtool will collect the callsites, and then the inline rewrite will hit the special case and replace the code with the magic instruction. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20251110115758.456717741@infradead.org
2025-11-24x86_64/bug: Implement __WARN_printf()Peter Zijlstra
The basic idea is to have __WARN_printf() be a vararg function such that the compiler can do the optimal calling convention for us. This function body will be a #UD and then set up a va_list in the exception from pt_regs. But because the trap will be in a called function, the bug_entry must be passed in. Have that be the first argument, with the format tucked away inside the bug_entry. The comments should clarify the real fun details. The big downside is that all WARNs will now show: RIP: 0010:__WARN_trap:+0 One possible solution is to simply discard the top frame when unwinding. A follow up patch takes care of this slightly differently by abusing the x86 static_call implementation. This changes (with the next patches): WARN_ONCE(preempt_count() != 2*PREEMPT_DISABLE_OFFSET, "corrupted preempt_count: %s/%d/0x%x\n", from: cmpl $2, %ecx #, _7 jne .L1472 ... .L1472: cmpb $0, __already_done.11(%rip) je .L1513 ... .L1513 movb $1, __already_done.11(%rip) movl 1424(%r14), %edx # _15->pid, _15->pid leaq 1912(%r14), %rsi #, _17 movq $.LC43, %rdi #, call __warn_printk # ud2 .pushsection __bug_table,"aw" 2: .long 1b - . # bug_entry::bug_addr .long .LC1 - . # bug_entry::file .word 5093 # bug_entry::line .word 2313 # bug_entry::flags .org 2b + 12 .popsection .pushsection .discard.annotate_insn,"M", @progbits, 8 .long 1b - . .long 8 # ANNOTYPE_REACHABLE .popsection into: cmpl $2, %ecx #, _7 jne .L1442 #, ... .L1442: lea (2f)(%rip), %rdi 1: .pushsection __bug_table,"aw" 2: .long 1b - . # bug_entry::bug_addr .long .LC43 - . # bug_entry::format .long .LC1 - . # bug_entry::file .word 5093 # bug_entry::line .word 2323 # bug_entry::flags .org 2b + 16 .popsection movl 1424(%r14), %edx # _19->pid, _19->pid leaq 1912(%r14), %rsi #, _13 ud1 (%edx), %rdi Notably, by pushing everything into the exception handler it can take care of the ONCE thing. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20251110115758.213813530@infradead.org
2025-11-24x86/ftrace: Implement DYNAMIC_FTRACE_WITH_JMPMenglong Dong
Implement the DYNAMIC_FTRACE_WITH_JMP for x86_64. In ftrace_call_replace, we will use JMP32_INSN_OPCODE instead of CALL_INSN_OPCODE if the address should use "jmp". Meanwhile, adjust the direct call in the ftrace_regs_caller. The RSB is balanced in the "jmp" mode. Take the function "foo" for example: original_caller: call foo -> foo: call fentry -> fentry: [do ftrace callbacks ] move tramp_addr to stack RET -> tramp_addr tramp_addr: [..] call foo_body -> foo_body: [..] RET -> back to tramp_addr [..] RET -> back to original_caller Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20251118123639.688444-3-dongml2@chinatelecom.cn Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-11-22x86/{boot,mtrr}: Remove unused function declarationsYue Haibing
Commits 28be1b454c2b ("x86/boot: Remove unused copy_*_gs() functions") 34d2819f2078 ("x86, mtrr: Remove unused mtrr/state.c") removed the functions but left the prototypes. Remove them. [ bp: Merge into a single patch. ] Signed-off-by: Yue Haibing <yuehaibing@huawei.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20251120121037.1479334-1-yuehaibing@huawei.com
2025-11-21x86,fs/resctrl: Implement "io_alloc" enable/disable handlersBabu Moger
"io_alloc" is the generic name of the new resctrl feature that enables system software to configure the portion of cache allocated for I/O traffic. On AMD systems, "io_alloc" resctrl feature is backed by AMD's L3 Smart Data Cache Injection Allocation Enforcement (SDCIAE). Introduce the architecture-specific functions that resctrl fs should call to enable, disable, or check status of the "io_alloc" feature. Change SDCIAE state by setting (to enable) or clearing (to disable) bit 1 of MSR_IA32_L3_QOS_EXT_CFG on all logical processors within the cache domain. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://patch.msgid.link/9e9070100c320eab5368e088a3642443dee95ed7.1762995456.git.babu.moger@amd.com
2025-11-21x86,fs/resctrl: Detect io_alloc featureBabu Moger
AMD's SDCIAE (SDCI Allocation Enforcement) PQE feature enables system software to control the portions of L3 cache used for direct insertion of data from I/O devices into the L3 cache. Introduce a generic resctrl cache resource property "io_alloc_capable" as the first part of the new "io_alloc" resctrl feature that will support AMD's SDCIAE. Any architecture can set a cache resource as "io_alloc_capable" if a portion of the cache can be allocated for I/O traffic. Set the "io_alloc_capable" property for the L3 cache resource on x86 (AMD) systems that support SDCIAE. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://patch.msgid.link/df85a9a6081674fd3ef6b4170920485512ce2ded.1762995456.git.babu.moger@amd.com
2025-11-21x86/resctrl: Add SDCIAE feature in the command line optionsBabu Moger
Add a kernel command-line parameter to enable or disable the exposure of the L3 Smart Data Cache Injection Allocation Enforcement (SDCIAE) hardware feature to resctrl. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://patch.msgid.link/c623edf7cb369ba9da966de47d9f1b666778a40e.1762995456.git.babu.moger@amd.com
2025-11-21x86/cpufeatures: Add support for L3 Smart Data Cache Injection Allocation ↵Babu Moger
Enforcement Smart Data Cache Injection (SDCI) is a mechanism that enables direct insertion of data from I/O devices into the L3 cache. By directly caching data from I/O devices rather than first storing the I/O data in DRAM, SDCI reduces demands on DRAM bandwidth and reduces latency to the processor consuming the I/O data. The SDCIAE (SDCI Allocation Enforcement) PQE feature allows system software to control the portion of the L3 cache used for SDCI. When enabled, SDCIAE forces all SDCI lines to be placed into the L3 cache partitions identified by the highest-supported L3_MASK_n register, where n is the maximum supported CLOSID. Add CPUID feature bit that can be used to configure SDCIAE. The SDCIAE feature details are documented in: AMD64 Architecture Programmer's Manual Volume 2: System Programming Publication # 24593 Revision 3.41 section 19.4.7 L3 Smart Data Cache Injection Allocation Enforcement (SDCIAE). available at https://bugzilla.kernel.org/show_bug.cgi?id=206537 Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/83ca10d981c48e86df2c3ad9658bb3ba3544c763.1762995456.git.babu.moger@amd.com
2025-11-21x86/mce: Handle AMD threshold interrupt stormsSmita Koralahalli
Extend the logic of handling CMCI storms to AMD threshold interrupts. Rely on the similar approach as of Intel's CMCI to mitigate storms per CPU and per bank. But, unlike CMCI, do not set thresholds and reduce interrupt rate on a storm. Rather, disable the interrupt on the corresponding CPU and bank. Re-enable back the interrupts if enough consecutive polls of the bank show no corrected errors (30, as programmed by Intel). Turning off the threshold interrupts would be a better solution on AMD systems as other error severities will still be handled even if the threshold interrupts are disabled. [ Tony: Small tweak because mce_handle_storm() isn't a pointer now ] [ Yazen: Rebase and simplify ] [ Avadhut: Remove check to not clear bank's bit in mce_poll_banks and fix checkpatch warnings. ] Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Avadhut Naik <avadhut.naik@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20251121190542.2447913-3-avadhut.naik@amd.com
2025-11-21x86/mce: Do not clear bank's poll bit in mce_poll_banks on AMD SMCA systemsAvadhut Naik
Currently, when a CMCI storm detected on a Machine Check bank, subsides, the bank's corresponding bit in the mce_poll_banks per-CPU variable is cleared unconditionally by cmci_storm_end(). On AMD SMCA systems, this essentially disables polling on that particular bank on that CPU. Consequently, any subsequent correctable errors or storms will not be logged. Since AMD SMCA systems allow banks to be managed by both polling and interrupts, the polling banks bitmap for a CPU, i.e., mce_poll_banks, should not be modified when a storm subsides. Fixes: 7eae17c4add5 ("x86/mce: Add per-bank CMCI storm mitigation") Signed-off-by: Avadhut Naik <avadhut.naik@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20251121190542.2447913-2-avadhut.naik@amd.com
2025-11-21x86/mce: Add support for physical address valid bitAvadhut Naik
Starting with Zen6, AMD's Scalable MCA systems will incorporate two new bits in MCA_STATUS and MCA_CONFIG MSRs. These bits will indicate if a valid System Physical Address (SPA) is present in MCA_ADDR. PhysAddrValidSupported bit (MCA_CONFIG[11]) serves as the architectural indicator and states if PhysAddrV bit (MCA_STATUS[54]) is Reserved or if it indicates validity of SPA in MCA_ADDR. PhysAddrV bit (MCA_STATUS[54]) advertises if MCA_ADDR contains valid SPA or if it is implementation specific. Use and prefer MCA_STATUS[PhysAddrV] when checking for a usable address. Signed-off-by: Avadhut Naik <avadhut.naik@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://patch.msgid.link/20251118191731.181269-1-avadhut.naik@amd.com
2025-11-21x86/mce: Save and use APEI corrected threshold limitYazen Ghannam
The MCA threshold limit generally is not something that needs to change during runtime. It is common for a system administrator to decide on a policy for their managed systems. If MCA thresholding is OS-managed, then the threshold limit must be set at every boot. However, many systems allow the user to set a value in their BIOS. And this is reported through an APEI HEST entry even if thresholding is not in FW-First mode. Use this value, if available, to set the OS-managed threshold limit. Users can still override it through sysfs if desired for testing or debug. APEI is parsed after MCE is initialized. So reset the thresholding blocks later to pick up the threshold limit. Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20251104-wip-mca-updates-v8-0-66c8eacf67b9@amd.com
2025-11-18x86/bugs: Use an x86 feature to track the MMIO Stale Data mitigationSean Christopherson
Convert the MMIO Stale Data mitigation tracking from a static branch into an x86 feature flag so that it can be used via ALTERNATIVE_2 in KVM. No functional change intended. Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Brendan Jackman <jackmanb@google.com> Link: https://patch.msgid.link/20251113233746.1703361-5-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-11-18x86/bugs: Use VM_CLEAR_CPU_BUFFERS in VMX as wellPawan Gupta
TSA mitigation: d8010d4ba43e ("x86/bugs: Add a Transient Scheduler Attacks mitigation") introduced VM_CLEAR_CPU_BUFFERS for guests on AMD CPUs. Currently on Intel CLEAR_CPU_BUFFERS is being used for guests which has a much broader scope (kernel->user also). Make mitigations on Intel consistent with TSA. This would help handling the guest-only mitigations better in future. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> [sean: make CLEAR_CPU_BUF_VM mutually exclusive with the MMIO mitigation] Acked-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Brendan Jackman <jackmanb@google.com> Link: https://patch.msgid.link/20251113233746.1703361-3-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-11-18x86/cpu: Enable LASS during CPU initializationSohil Mehta
Linear Address Space Separation (LASS) mitigates a class of side-channel attacks that rely on speculative access across the user/kernel boundary. Enable LASS along with similar security features if the platform supports it. While at it, remove the comment above the SMAP/SMEP/UMIP/LASS setup instead of updating it, as the whole sequence is quite self-explanatory. Some EFI runtime and boot services may rely on 1:1 mappings in the lower half during early boot and even after SetVirtualAddressMap(). To avoid tripping LASS, the initial CR4 programming would need to be delayed until EFI has completely finished entering virtual mode (including efi_free_boot_services()). Also, LASS would need to be temporarily disabled while switching to efi_mm to avoid potential faults on stray runtime accesses. Similarly, legacy vsyscall page accesses are flagged by LASS resulting in a #GP (instead of a #PF). Without LASS, the #PF handler emulates the accesses and returns the appropriate values. Equivalent emulation support is required in the #GP handler with LASS enabled. In case of vsyscall XONLY (execute only) mode, the faulting address is readily available in the RIP which would make it easier to reuse the #PF emulation logic. For now, keep it simple and disable LASS if either of those are compiled in. Though not ideal, this makes it easier to start testing LASS support in some environments. In future, LASS support can easily be expanded to support EFI and legacy vsyscalls. Signed-off-by: Sohil Mehta <sohil.mehta@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://patch.msgid.link/20251118182911.2983253-9-sohil.mehta%40intel.com