1490 Commits
Author SHA1 Message Date
Borislav Petkov (AMD)andIngo Molnar 80501dff81 Documentation/arch/x86: Hide clearcpuid=
This option was never meant to be used in production because it solely
clears the X86_FEATURE kernel-internal representation of what CPUID bits
it has detected and doesn't do any *proper* feature disablement like
clearing CR4.CET in the user shadow stack case, for example.

So remove its documentation so that it doesn't get used in production
and people get silly ideas. It is meant strictly for debugging; and if
a chicken bit for properly disabling a feature is warranted, then that
would need proper enablement.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Mathias Krause <minipli@grsecurity.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://patch.msgid.link/20260520202508.160112-1-bp@kernel.org
2026-05-26 05:37:20 +02:00
Linus Torvalds 64edfa6506 Merge tag 'net-deletions' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking deletions from Jakub Kicinski:
 "Delete some obsolete networking code

  Old code like amateur radio and NFC have long been a burden to core
  networking developers. syzbot loves to find bugs in BKL-era code, and
  noobs try to fix them.

  If we want to have a fighting chance of surviving the LLM-pocalypse
  this code needs to find a dedicated owner or get deleted. We've talked
  about these deletions multiple times in the past and every time
  someone wanted the code to stay. It is never very clear to me how many
  of those people actually use the code vs are just nostalgic to see it
  go. Amateur radio did have occasional users (or so I think) but most
  users switched to user space implementations since its all super slow
  stuff. Nobody stepped up to maintain the kernel code.

  We were lucky enough to find someone who wants to help with NFC so
  we're giving that a chance. Let's try to put the rest of this code
  behind us"

* tag 'net-deletions' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next:
  drivers: net: 8390: wd80x3: Remove this driver
  drivers: net: 8390: ultra: Remove this driver
  drivers: net: 8390: AX88190: Remove this driver
  drivers: net: fujitsu: fmvj18x: Remove this driver
  drivers: net: smsc: smc91c92: Remove this driver
  drivers: net: smsc: smc9194: Remove this driver
  drivers: net: amd: nmclan: Remove this driver
  drivers: net: amd: lance: Remove this driver
  drivers: net: 3com: 3c589: Remove this driver
  drivers: net: 3com: 3c574: Remove this driver
  drivers: net: 3com: 3c515: Remove this driver
  drivers: net: 3com: 3c509: Remove this driver
  net: packetengines: remove obsolete yellowfin driver and vendor dir
  net: packetengines: remove obsolete hamachi driver
  net: remove unused ATM protocols and legacy ATM device drivers
  net: remove ax25 and amateur radio (hamradio) subsystem
  net: remove ISDN subsystem and Bluetooth CMTP
  caif: remove CAIF NETWORK LAYER
2026-04-24 09:41:58 -07:00
Jakub Kicinski dd8d4bc28a net: remove ax25 and amateur radio (hamradio) subsystem
Remove the amateur radio (AX.25, NET/ROM, ROSE) protocol implementation
and all associated hamradio device drivers from the kernel tree.
This set of protocols has long been a huge bug/syzbot magnet,
and since nobody stepped up to help us deal with the influx
of the AI-generated bug reports we need to move it out of tree
to protect our sanity.

The code is moved to an out-of-tree repo:
https://github.com/linux-netdev/mod-orphan
if it's cleaned up and reworked there we can accept it back.

Minimal stub headers are kept for include/net/ax25.h (AX25_P_IP,
AX25_ADDR_LEN, ax25_address) and include/net/rose.h (ROSE_ADDR_LEN)
so that the conditional integration code in arp.c and tun.c continues
to compile and work when the out-of-tree modules are loaded.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Carlos Bilbao <carlos.bilbao@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://patch.msgid.link/20260421021824.1293976-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-04-23 10:24:02 -07:00
Linus Torvalds 9cdca33667 Merge tag 'integrity-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
 "There are two main changes, one feature removal, some code cleanup,
  and a number of bug fixes.

  Main changes:
   - Detecting secure boot mode was limited to IMA. Make detecting
     secure boot mode accessible to EVM and other LSMs
   - IMA sigv3 support was limited to fsverity. Add IMA sigv3 support
     for IMA regular file hashes and EVM portable signatures

  Remove:
   - Remove IMA support for asychronous hash calculation originally
     added for hardware acceleration

  Cleanup:
   - Remove unnecessary Kconfig CONFIG_MODULE_SIG and CONFIG_KEXEC_SIG
     tests
   - Add descriptions of the IMA atomic flags

  Bug fixes:
   - Like IMA, properly limit EVM "fix" mode
   - Define and call evm_fix_hmac() to update security.evm
   - Fallback to using i_version to detect file change for filesystems
     that do not support STATX_CHANGE_COOKIE
   - Address missing kernel support for configured (new) TPM hash
     algorithms
   - Add missing crypto_shash_final() return value"

* tag 'integrity-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  evm: Enforce signatures version 3 with new EVM policy 'bit 3'
  integrity: Allow sigv3 verification on EVM_XATTR_PORTABLE_DIGSIG
  ima: add support to require IMA sigv3 signatures
  ima: add regular file data hash signature version 3 support
  ima: Define asymmetric_verify_v3() to verify IMA sigv3 signatures
  ima: remove buggy support for asynchronous hashes
  integrity: Eliminate weak definition of arch_get_secureboot()
  ima: Add code comments to explain IMA iint cache atomic_flags
  ima_fs: Correctly create securityfs files for unsupported hash algos
  ima: check return value of crypto_shash_final() in boot aggregate
  ima: Define and use a digest_size field in the ima_algo_desc structure
  powerpc/ima: Drop unnecessary check for CONFIG_MODULE_SIG
  ima: efi: Drop unnecessary check for CONFIG_MODULE_SIG/CONFIG_KEXEC_SIG
  ima: fallback to using i_version to detect file change
  evm: fix security.evm for a file with IMA signature
  s390: Drop unnecessary CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT
  evm: Don't enable fix mode when secure boot is enabled
  integrity: Make arch_ima_get_secureboot integrity-wide
2026-04-17 15:42:01 -07:00
Linus Torvalds 01f492e181 Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
 "Arm:

   - Add support for tracing in the standalone EL2 hypervisor code,
     which should help both debugging and performance analysis. This
     uses the new infrastructure for 'remote' trace buffers that can be
     exposed by non-kernel entities such as firmware, and which came
     through the tracing tree

   - Add support for GICv5 Per Processor Interrupts (PPIs), as the
     starting point for supporting the new GIC architecture in KVM

   - Finally add support for pKVM protected guests, where pages are
     unmapped from the host as they are faulted into the guest and can
     be shared back from the guest using pKVM hypercalls. Protected
     guests are created using a new machine type identifier. As the
     elusive guestmem has not yet delivered on its promises, anonymous
     memory is also supported

     This is only a first step towards full isolation from the host; for
     example, the CPU register state and DMA accesses are not yet
     isolated. Because this does not really yet bring fully what it
     promises, it is hidden behind CONFIG_ARM_PKVM_GUEST +
     'kvm-arm.mode=protected', and also triggers TAINT_USER when a VM is
     created. Caveat emptor

   - Rework the dreaded user_mem_abort() function to make it more
     maintainable, reducing the amount of state being exposed to the
     various helpers and rendering a substantial amount of state
     immutable

   - Expand the Stage-2 page table dumper to support NV shadow page
     tables on a per-VM basis

   - Tidy up the pKVM PSCI proxy code to be slightly less hard to
     follow

   - Fix both SPE and TRBE in non-VHE configurations so that they do not
     generate spurious, out of context table walks that ultimately lead
     to very bad HW lockups

   - A small set of patches fixing the Stage-2 MMU freeing in error
     cases

   - Tighten-up accepted SMC immediate value to be only #0 for host
     SMCCC calls

   - The usual cleanups and other selftest churn

  LoongArch:

   - Use CSR_CRMD_PLV for kvm_arch_vcpu_in_kernel()

   - Add DMSINTC irqchip in kernel support

  RISC-V:

   - Fix steal time shared memory alignment checks

   - Fix vector context allocation leak

   - Fix array out-of-bounds in pmu_ctr_read() and pmu_fw_ctr_read_hi()

   - Fix double-free of sdata in kvm_pmu_clear_snapshot_area()

   - Fix integer overflow in kvm_pmu_validate_counter_mask()

   - Fix shift-out-of-bounds in make_xfence_request()

   - Fix lost write protection on huge pages during dirty logging

   - Split huge pages during fault handling for dirty logging

   - Skip CSR restore if VCPU is reloaded on the same core

   - Implement kvm_arch_has_default_irqchip() for KVM selftests

   - Factored-out ISA checks into separate sources

   - Added hideleg to struct kvm_vcpu_config

   - Factored-out VCPU config into separate sources

   - Support configuration of per-VM HGATP mode from KVM user space

  s390:

   - Support for ESA (31-bit) guests inside nested hypervisors

   - Remove restriction on memslot alignment, which is not needed
     anymore with the new gmap code

   - Fix LPSW/E to update the bear (which of course is the breaking
     event address register)

  x86:

   - Shut up various UBSAN warnings on reading module parameter before
     they were initialized

   - Don't zero-allocate page tables that are used for splitting
     hugepages in the TDP MMU, as KVM is guaranteed to set all SPTEs in
     the page table and thus write all bytes

   - As an optimization, bail early when trying to unsync 4KiB mappings
     if the target gfn can just be mapped with a 2MiB hugepage

  x86 generic:

   - Copy single-chunk MMIO write values into struct kvm_vcpu (more
     precisely struct kvm_mmio_fragment) to fix use-after-free stack
     bugs where KVM would dereference stack pointer after an exit to
     userspace

   - Clean up and comment the emulated MMIO code to try to make it
     easier to maintain (not necessarily "easy", but "easier")

   - Move VMXON+VMXOFF and EFER.SVME toggling out of KVM (not *all* of
     VMX and SVM enabling) as it is needed for trusted I/O

   - Advertise support for AVX512 Bit Matrix Multiply (BMM) instructions

   - Immediately fail the build if a required #define is missing in one
     of KVM's headers that is included multiple times

   - Reject SET_GUEST_DEBUG with -EBUSY if there's an already injected
     exception, mostly to prevent syzkaller from abusing the uAPI to
     trigger WARNs, but also because it can help prevent userspace from
     unintentionally crashing the VM

   - Exempt SMM from CPUID faulting on Intel, as per the spec

   - Misc hardening and cleanup changes

  x86 (AMD):

   - Fix and optimize IRQ window inhibit handling for AVIC; make it
     per-vCPU so that KVM doesn't prematurely re-enable AVIC if multiple
     vCPUs have to-be-injected IRQs

   - Clean up and optimize the OSVW handling, avoiding a bug in which
     KVM would overwrite state when enabling virtualization on multiple
     CPUs in parallel. This should not be a problem because OSVW should
     usually be the same for all CPUs

   - Drop a WARN in KVM_MEMORY_ENCRYPT_REG_REGION where KVM complains
     about a "too large" size based purely on user input

   - Clean up and harden the pinning code for KVM_MEMORY_ENCRYPT_REG_REGION

   - Disallow synchronizing a VMSA of an already-launched/encrypted
     vCPU, as doing so for an SNP guest will crash the host due to an
     RMP violation page fault

   - Overhaul KVM's APIs for detecting SEV+ guests so that VM-scoped
     queries are required to hold kvm->lock, and enforce it by lockdep.
     Fix various bugs where sev_guest() was not ensured to be stable for
     the whole duration of a function or ioctl

   - Convert a pile of kvm->lock SEV code to guard()

   - Play nicer with userspace that does not enable
     KVM_CAP_EXCEPTION_PAYLOAD, for which KVM needs to set CR2 and DR6
     as a response to ioctls such as KVM_GET_VCPU_EVENTS (even if the
     payload would end up in EXITINFO2 rather than CR2, for example).
     Only set CR2 and DR6 when consumption of the payload is imminent,
     but on the other hand force delivery of the payload in all paths
     where userspace retrieves CR2 or DR6

   - Use vcpu->arch.cr2 when updating vmcb12's CR2 on nested #VMEXIT
     instead of vmcb02->save.cr2. The value is out of sync after a
     save/restore or after a #PF is injected into L2

   - Fix a class of nSVM bugs where some fields written by the CPU are
     not synchronized from vmcb02 to cached vmcb12 after VMRUN, and so
     are not up-to-date when saved by KVM_GET_NESTED_STATE

   - Fix a class of bugs where the ordering between KVM_SET_NESTED_STATE
     and KVM_SET_{S}REGS could cause vmcb02 to be incorrectly
     initialized after save+restore

   - Add a variety of missing nSVM consistency checks

   - Fix several bugs where KVM failed to correctly update VMCB fields
     on nested #VMEXIT

   - Fix several bugs where KVM failed to correctly synthesize #UD or
     #GP for SVM-related instructions

   - Add support for save+restore of virtualized LBRs (on SVM)

   - Refactor various helpers and macros to improve clarity and
     (hopefully) make the code easier to maintain

   - Aggressively sanitize fields when copying from vmcb12, to guard
     against unintentionally allowing L1 to utilize yet-to-be-defined
     features

   - Fix several bugs where KVM botched rAX legality checks when
     emulating SVM instructions. There are remaining issues in that KVM
     doesn't handle size prefix overrides for 64-bit guests

   - Fail emulation of VMRUN/VMLOAD/VMSAVE if mapping vmcb12 fails
     instead of somewhat arbitrarily synthesizing #GP (i.e. don't double
     down on AMD's architectural but sketchy behavior of generating #GP
     for "unsupported" addresses)

   - Cache all used vmcb12 fields to further harden against TOCTOU bugs

  x86 (Intel):

   - Drop obsolete branch hint prefixes from the VMX instruction macros

   - Use ASM_INPUT_RM() in __vmcs_writel() to coerce clang into using a
     register input when appropriate

   - Code cleanups

  guest_memfd:

   - Don't mark guest_memfd folios as accessed, as guest_memfd doesn't
     support reclaim, the memory is unevictable, and there is no storage
     to write back to

  LoongArch selftests:

   - Add KVM PMU test cases

  s390 selftests:

   - Enable more memory selftests

  x86 selftests:

   - Add support for Hygon CPUs in KVM selftests

   - Fix a bug in the MSR test where it would get false failures on
     AMD/Hygon CPUs with exactly one of RDPID or RDTSCP

   - Add an MADV_COLLAPSE testcase for guest_memfd as a regression test
     for a bug where the kernel would attempt to collapse guest_memfd
     folios against KVM's will"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (373 commits)
  KVM: x86: use inlines instead of macros for is_sev_*guest
  x86/virt: Treat SVM as unsupported when running as an SEV+ guest
  KVM: SEV: Goto an existing error label if charging misc_cg for an ASID fails
  KVM: SVM: Move lock-protected allocation of SEV ASID into a separate helper
  KVM: SEV: use mutex guard in snp_handle_guest_req()
  KVM: SEV: use mutex guard in sev_mem_enc_unregister_region()
  KVM: SEV: use mutex guard in sev_mem_enc_ioctl()
  KVM: SEV: use mutex guard in snp_launch_update()
  KVM: SEV: Assert that kvm->lock is held when querying SEV+ support
  KVM: SEV: Document that checking for SEV+ guests when reclaiming memory is "safe"
  KVM: SEV: Hide "struct kvm_sev_info" behind CONFIG_KVM_AMD_SEV=y
  KVM: SEV: WARN on unhandled VM type when initializing VM
  KVM: LoongArch: selftests: Add PMU overflow interrupt test
  KVM: LoongArch: selftests: Add basic PMU event counting test
  KVM: LoongArch: selftests: Add cpucfg read/write helpers
  LoongArch: KVM: Add DMSINTC inject msi to vCPU
  LoongArch: KVM: Add DMSINTC device support
  LoongArch: KVM: Make vcpu_is_preempted() as a macro rather than function
  LoongArch: KVM: Move host CSR_GSTAT save and restore in context switch
  LoongArch: KVM: Move host CSR_EENTRY save and restore in context switch
  ...
2026-04-17 07:18:03 -07:00
Linus Torvalds 334fbe734e Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:

 - "maple_tree: Replace big node with maple copy" (Liam Howlett)

   Mainly prepararatory work for ongoing development but it does reduce
   stack usage and is an improvement.

 - "mm, swap: swap table phase III: remove swap_map" (Kairui Song)

   Offers memory savings by removing the static swap_map. It also yields
   some CPU savings and implements several cleanups.

 - "mm: memfd_luo: preserve file seals" (Pratyush Yadav)

   File seal preservation to LUO's memfd code

 - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
   Chen)

   Additional userspace stats reportng to zswap

 - "arch, mm: consolidate empty_zero_page" (Mike Rapoport)

   Some cleanups for our handling of ZERO_PAGE() and zero_pfn

 - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
   Han)

   A robustness improvement and some cleanups in the kmemleak code

 - "Improve khugepaged scan logic" (Vernon Yang)

   Improve khugepaged scan logic and reduce CPU consumption by
   prioritizing scanning tasks that access memory frequently

 - "Make KHO Stateless" (Jason Miu)

   Simplify Kexec Handover by transitioning KHO from an xarray-based
   metadata tracking system with serialization to a radix tree data
   structure that can be passed directly to the next kernel

 - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
   Ballasi and Steven Rostedt)

   Enhance vmscan's tracepointing

 - "mm: arch/shstk: Common shadow stack mapping helper and
   VM_NOHUGEPAGE" (Catalin Marinas)

   Cleanup for the shadow stack code: remove per-arch code in favour of
   a generic implementation

 - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)

   Fix a WARN() which can be emitted the KHO restores a vmalloc area

 - "mm: Remove stray references to pagevec" (Tal Zussman)

   Several cleanups, mainly udpating references to "struct pagevec",
   which became folio_batch three years ago

 - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
   Shutsemau)

   Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
   pages encode their relationship to the head page

 - "mm/damon/core: improve DAMOS quota efficiency for core layer
   filters" (SeongJae Park)

   Improve two problematic behaviors of DAMOS that makes it less
   efficient when core layer filters are used

 - "mm/damon: strictly respect min_nr_regions" (SeongJae Park)

   Improve DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter

 - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)

   The proper fix for a previously hotfixed SMP=n issue. Code
   simplifications and cleanups ensued

 - "mm: cleanups around unmapping / zapping" (David Hildenbrand)

   A bunch of cleanups around unmapping and zapping. Mostly
   simplifications, code movements, documentation and renaming of
   zapping functions

 - "support batched checking of the young flag for MGLRU" (Baolin Wang)

   Batched checking of the young flag for MGLRU. It's part cleanups; one
   benchmark shows large performance benefits for arm64

 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)

   memcg cleanup and robustness improvements

 - "Allow order zero pages in page reporting" (Yuvraj Sakshith)

   Enhance free page reporting - it is presently and undesirably order-0
   pages when reporting free memory.

 - "mm: vma flag tweaks" (Lorenzo Stoakes)

   Cleanup work following from the recent conversion of the VMA flags to
   a bitmap

 - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
   Park)

   Add some more developer-facing debug checks into DAMON core

 - "mm/damon: test and document power-of-2 min_region_sz requirement"
   (SeongJae Park)

   An additional DAMON kunit test and makes some adjustments to the
   addr_unit parameter handling

 - "mm/damon/core: make passed_sample_intervals comparisons
   overflow-safe" (SeongJae Park)

   Fix a hard-to-hit time overflow issue in DAMON core

 - "mm/damon: improve/fixup/update ratio calculation, test and
   documentation" (SeongJae Park)

   A batch of misc/minor improvements and fixups for DAMON

 - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
   Hildenbrand)

   Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
   movement was required.

 - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)

   A somewhat random mix of fixups, recompression cleanups and
   improvements in the zram code

 - "mm/damon: support multiple goal-based quota tuning algorithms"
   (SeongJae Park)

   Extend DAMOS quotas goal auto-tuning to support multiple tuning
   algorithms that users can select

 - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)

   Fix the khugpaged sysfs handling so we no longer spam the logs with
   reams of junk when starting/stopping khugepaged

 - "mm: improve map count checks" (Lorenzo Stoakes)

   Provide some cleanups and slight fixes in the mremap, mmap and vma
   code

 - "mm/damon: support addr_unit on default monitoring targets for
   modules" (SeongJae Park)

   Extend the use of DAMON core's addr_unit tunable

 - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)

   Cleanups to khugepaged and is a base for Nico's planned khugepaged
   mTHP support

 - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)

   Code movement and cleanups in the memhotplug and sparsemem code

 - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
   CONFIG_MIGRATION" (David Hildenbrand)

   Rationalize some memhotplug Kconfig support

 - "change young flag check functions to return bool" (Baolin Wang)

   Cleanups to change all young flag check functions to return bool

 - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
   Law and SeongJae Park)

   Fix a few potential DAMON bugs

 - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
   Stoakes)

   Convert a lot of the existing use of the legacy vm_flags_t data type
   to the new vma_flags_t type which replaces it. Mainly in the vma
   code.

 - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)

   Expand the mmap_prepare functionality, which is intended to replace
   the deprecated f_op->mmap hook which has been the source of bugs and
   security issues for some time. Cleanups, documentation, extension of
   mmap_prepare into filesystem drivers

 - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)

   Simplify and clean up zap_huge_pmd(). Additional cleanups around
   vm_normal_folio_pmd() and the softleaf functionality are performed.

* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm: fix deferred split queue races during migration
  mm/khugepaged: fix issue with tracking lock
  mm/huge_memory: add and use has_deposited_pgtable()
  mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
  mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
  mm/huge_memory: separate out the folio part of zap_huge_pmd()
  mm/huge_memory: use mm instead of tlb->mm
  mm/huge_memory: remove unnecessary sanity checks
  mm/huge_memory: deduplicate zap deposited table call
  mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
  mm/huge_memory: add a common exit path to zap_huge_pmd()
  mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
  mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
  mm/huge: avoid big else branch in zap_huge_pmd()
  mm/huge_memory: simplify vma_is_specal_huge()
  mm: on remap assert that input range within the proposed VMA
  mm: add mmap_action_map_kernel_pages[_full]()
  uio: replace deprecated mmap hook with mmap_prepare in uio_info
  drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
  mm: allow handling of stacked mmap_prepare hooks in more drivers
  ...
2026-04-15 12:59:16 -07:00
Linus Torvalds 7de6b4a246 Merge tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue updates from Tejun Heo:

 - New default WQ_AFFN_CACHE_SHARD affinity scope subdivides LLCs into
   smaller shards to improve scalability on machines with many CPUs per
   LLC

 - Misc:
    - system_dfl_long_wq for long unbound works
    - devm_alloc_workqueue() for device-managed allocation
    - sysfs exposure for ordered workqueues and the EFI workqueue
    - removal of HK_TYPE_WQ from wq_unbound_cpumask
    - various small fixes

* tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (21 commits)
  workqueue: validate cpumask_first() result in llc_populate_cpu_shard_id()
  workqueue: use NR_STD_WORKER_POOLS instead of hardcoded value
  workqueue: avoid unguarded 64-bit division
  docs: workqueue: document WQ_AFFN_CACHE_SHARD affinity scope
  workqueue: add test_workqueue benchmark module
  tools/workqueue: add CACHE_SHARD support to wq_dump.py
  workqueue: set WQ_AFFN_CACHE_SHARD as the default affinity scope
  workqueue: add WQ_AFFN_CACHE_SHARD affinity scope
  workqueue: fix typo in WQ_AFFN_SMT comment
  workqueue: Remove HK_TYPE_WQ from affecting wq_unbound_cpumask
  workqueue: unlink pwqs from wq->pwqs list in alloc_and_link_pwqs() error path
  workqueue: Remove NULL wq WARN in __queue_delayed_work()
  workqueue: fix parse_affn_scope() prefix matching bug
  workqueue: devres: Add device-managed allocate workqueue
  workqueue: Add system_dfl_long_wq for long unbound works
  tools/workqueue/wq_dump.py: add NODE prefix to all node columns
  tools/workqueue/wq_dump.py: fix column alignment in node_nr/max_active section
  tools/workqueue/wq_dump.py: remove backslash separator from node_nr/max_active header
  efi: Allow to expose the workqueue via sysfs
  workqueue: Allow to expose ordered workqueues via sysfs
  ...
2026-04-15 10:32:08 -07:00
Linus Torvalds e9635f2a73 Merge tag 'x86_fred_for_v7.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 FRED updates from Borislav Petkov:
 "We made the FRED support an opt-in initially out of fear of it
  breaking machines left and right in the case of a hw bug in the first
  generation of machines supporting it.

  Now that that the FRED code has seen a lot of hammering, flip the
  logic to be opt-out as is the usual case with new hw features"

* tag 'x86_fred_for_v7.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fred: Remove kernel log message when initializing exceptions
  x86/fred: Enable FRED by default
2026-04-14 14:50:51 -07:00
Linus Torvalds 9f2bb6c7b3 Merge tag 'x86_cpu_for_7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu updates from Dave Hansen:

 - Complete LASS enabling: deal with vsyscall and EFI

   The existing Linear Address Space Separation (LASS) support punted
   on support for common EFI and vsyscall configs. Complete the
   implementation by supporting EFI and vsyscall=xonly.

 - Clean up CPUID usage in newer Intel "avs" audio driver and update the
   x86-cpuid-db file

* tag 'x86_cpu_for_7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/x86/kcpuid: Update bitfields to x86-cpuid-db v3.0
  ASoC: Intel: avs: Include CPUID header at file scope
  ASoC: Intel: avs: Check maximum valid CPUID leaf
  x86/cpu: Remove LASS restriction on vsyscall emulation
  x86/vsyscall: Disable LASS if vsyscall mode is set to EMULATE
  x86/vsyscall: Restore vsyscall=xonly mode under LASS
  x86/traps: Consolidate user fixups in the #GP handler
  x86/vsyscall: Reorganize the page fault emulation code
  x86/cpu: Remove LASS restriction on EFI
  x86/efi: Disable LASS while executing runtime services
  x86/cpu: Defer LASS enabling until userspace comes up
2026-04-14 14:24:45 -07:00
Linus Torvalds c1fe867b5b Merge tag 'timers-core-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer core updates from Thomas Gleixner:

 - A rework of the hrtimer subsystem to reduce the overhead for
   frequently armed timers, especially the hrtick scheduler timer:

     - Better timer locality decision

     - Simplification of the evaluation of the first expiry time by
       keeping track of the neighbor timers in the RB-tree by providing
       a RB-tree variant with neighbor links. That avoids walking the
       RB-tree on removal to find the next expiry time, but even more
       important allows to quickly evaluate whether a timer which is
       rearmed changes the position in the RB-tree with the modified
       expiry time or not. If not, the dequeue/enqueue sequence which
       both can end up in rebalancing can be completely avoided.

     - Deferred reprogramming of the underlying clock event device. This
       optimizes for the situation where a hrtimer callback sets the
       need resched bit. In that case the code attempts to defer the
       re-programming of the clock event device up to the point where
       the scheduler has picked the next task and has the next hrtick
       timer armed. In case that there is no immediate reschedule or
       soft interrupts have to be handled before reaching the reschedule
       point in the interrupt entry code the clock event is reprogrammed
       in one of those code paths to prevent that the timer becomes
       stale.

     - Support for clocksource coupled clockevents

       The TSC deadline timer is coupled to the TSC. The next event is
       programmed in TSC time. Currently this is done by converting the
       CLOCK_MONOTONIC based expiry value into a relative timeout,
       converting it into TSC ticks, reading the TSC adding the delta
       ticks and writing the deadline MSR.

       As the timekeeping core has the conversion factors for the TSC
       already, the whole back and forth conversion can be completely
       avoided. The timekeeping core calculates the reverse conversion
       factors from nanoseconds to TSC ticks and utilizes the base
       timestamps of TSC and CLOCK_MONOTONIC which are updated once per
       tick. This allows a direct conversion into the TSC deadline value
       without reading the time and as a bonus keeps the deadline
       conversion in sync with the TSC conversion factors, which are
       updated by adjtimex() on systems with NTP/PTP enabled.

     - Allow inlining of the clocksource read and clockevent write
       functions when they are tiny enough, e.g. on x86 RDTSC and WRMSR.

   With all those enhancements in place a hrtick enabled scheduler
   provides the same performance as without hrtick. But also other
   hrtimer users obviously benefit from these optimizations.

 - Robustness improvements and cleanups of historical sins in the
   hrtimer and timekeeping code.

 - Rewrite of the clocksource watchdog.

   The clocksource watchdog code has over time reached the state of an
   impenetrable maze of duct tape and staples. The original design,
   which was made in the context of systems far smaller than today, is
   based on the assumption that the to be monitored clocksource (TSC)
   can be trivially compared against a known to be stable clocksource
   (HPET/ACPI-PM timer).

   Over the years this rather naive approach turned out to have major
   flaws. Long delays between the watchdog invocations can cause wrap
   arounds of the reference clocksource. The access to the reference
   clocksource degrades on large multi-sockets systems dure to
   interconnect congestion. This has been addressed with various
   heuristics which degraded the accuracy of the watchdog to the point
   that it fails to detect actual TSC problems on older hardware which
   exposes slow inter CPU drifts due to firmware manipulating the TSC to
   hide SMI time.

   The rewrite addresses this by:

     - Restricting the validation against the reference clocksource to
       the boot CPU which is usually closest to the legacy block which
       contains the reference clocksource (HPET/ACPI-PM).

     - Do a round robin validation betwen the boot CPU and the other
       CPUs based only on the TSC with an algorithm similar to the TSC
       synchronization code during CPU hotplug.

     - Being more leniant versus remote timeouts

 - The usual tiny fixes, cleanups and enhancements all over the place

* tag 'timers-core-2026-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
  alarmtimer: Access timerqueue node under lock in suspend
  hrtimer: Fix incorrect #endif comment for BITS_PER_LONG check
  posix-timers: Fix stale function name in comment
  timers: Get this_cpu once while clearing the idle state
  clocksource: Rewrite watchdog code completely
  clocksource: Don't use non-continuous clocksources as watchdog
  x86/tsc: Handle CLOCK_SOURCE_VALID_FOR_HRES correctly
  MIPS: Don't select CLOCKSOURCE_WATCHDOG
  parisc: Remove unused clocksource flags
  hrtimer: Add a helper to retrieve a hrtimer from its timerqueue node
  hrtimer: Remove trailing comma after HRTIMER_MAX_CLOCK_BASES
  hrtimer: Mark index and clockid of clock base as const
  hrtimer: Drop unnecessary pointer indirection in hrtimer_expire_entry event
  hrtimer: Drop spurious space in 'enum hrtimer_base_type'
  hrtimer: Don't zero-initialize ret in hrtimer_nanosleep()
  hrtimer: Remove hrtimer_get_expires_ns()
  timekeeping: Mark offsets array as const
  timekeeping/auxclock: Consistently use raw timekeeper for tk_setup_internals()
  timer_list: Print offset as signed integer
  tracing: Use explicit array size instead of sentinel elements in symbol printing
  ...
2026-04-14 10:27:07 -07:00
Linus Torvalds 5181afcdf9 Merge tag 'docs-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux
Pull documentation updates from Jonathan Corbet:
 "A busier cycle than I had expected for docs, including:

   - Translations: some overdue updates to the Japanese translations,
     Chinese translations for some of the Rust documentation, and the
     beginnings of a Portuguese translation.

   - New documents covering CPU isolation, managed interrupts, debugging
     Python gbb scripts, and more.

   - More tooling work from Mauro, reducing docs-build warnings, adding
     self tests, improving man-page output, bringing in a proper C
     tokenizer to replace (some of) the mess of kernel-doc regexes, and
     more.

   - Update and synchronize changes.rst and scripts/ver_linux, and put
     both into alphabetical order.

  ... and a long list of documentation updates, typo fixes, and general
  improvements"

* tag 'docs-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (162 commits)
  Documentation: core-api: real-time: correct spelling
  doc: Add CPU Isolation documentation
  Documentation: Add managed interrupts
  Documentation: seq_file: drop 2.6 reference
  docs/zh_CN: update rust/index.rst translation
  docs/zh_CN: update rust/quick-start.rst translation
  docs/zh_CN: update rust/coding-guidelines.rst translation
  docs/zh_CN: update rust/arch-support.rst translation
  docs/zh_CN: sync process/2.Process.rst with English version
  docs/zh_CN: fix an inconsistent statement in dev-tools/testing-overview
  tracing: Documentation: Update histogram-design.rst for fn() handling
  docs: sysctl: Add documentation for /proc/sys/xen/
  Docs: hid: intel-ish-hid: make long URL usable
  Documentation/kernel-parameters: fix architecture alignment for pt, nopt, and nobypass
  sched/doc: Update yield_task description in sched-design-CFS
  Documentation/rtla: Convert links to RST format
  docs: fix typos and duplicated words across documentation
  docs: fix typo in zoran driver documentation
  docs: add an Assisted-by mention to submitting-patches.rst
  Revert "scripts/checkpatch: add Assisted-by: tag validation"
  ...
2026-04-14 08:47:08 -07:00
Linus Torvalds d7c8087a9c Merge tag 'pm-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
 "Once again, cpufreq is the most active development area, mostly
  because of the new feature additions and documentation updates in the
  amd-pstate driver, but there are also changes in the cpufreq core
  related to boost support and other assorted updates elsewhere.

  Next up are power capping changes due to the major cleanup of the
  Intel RAPL driver.

  On the cpuidle front, a new C-states table for Intel Panther Lake is
  added to the intel_idle driver, the stopped tick handling in the menu
  and teo governors is updated, and there are a couple of cleanups.

  Apart from the above, support for Tegra114 is added to devfreq and
  there are assorted cleanups of that code, there are also two updates
  of the operating performance points (OPP) library, two minor updates
  related to hibernation, and cpupower utility man pages updates and
  cleanups.

  Specifics:

   - Update qcom-hw DT bindings to include Eliza hardware (Abel Vesa)

   - Update cpufreq-dt-platdev blocklist (Faruque Ansari)

   - Minor updates to driver and dt-bindings for Tegra (Thierry Reding,
     Rosen Penev)

   - Add MAINTAINERS entry for CPPC driver (Viresh Kumar)

   - Add support for new features: CPPC performance priority, Dynamic
     EPP, Raw EPP, and new unit tests for them to amd-pstate (Gautham
     Shenoy, Mario Limonciello)

   - Fix sysfs files being present when HW missing and broken/outdated
     documentation in the amd-pstate driver (Ninad Naik, Gautham Shenoy)

   - Pass the policy to cpufreq_driver->adjust_perf() to avoid using
     cpufreq_cpu_get() in the .adjust_perf() callback in amd-pstate
     which leads to a scheduling-while-atomic bug (K Prateek Nayak)

   - Clean up dead code in Kconfig for cpufreq (Julian Braha)

   - Remove max_freq_req update for pre-existing cpufreq policy and add
     a boost_freq_req QoS request to save the boost constraint instead
     of overwriting the last scaling_max_freq constraint (Pierre
     Gondois)

   - Embed cpufreq QoS freq_req objects in cpufreq policy so they all
     are allocated in one go along with the policy to simplify lifetime
     rules and avoid error handling issues (Viresh Kumar)

   - Use DMI max speed when CPPC is unavailable in the acpi-cpufreq
     scaling driver (Henry Tseng)

   - Switch policy_is_shared() in cpufreq to using cpumask_nth() instead
     of cpumask_weight() because the former is more efficient (Yury
     Norov)

   - Use sysfs_emit() in sysfs show functions for cpufreq governor
     attributes (Thorsten Blum)

   - Update intel_pstate to stop returning an error when "off" is
     written to its status sysfs attribute while the driver is already
     off (Fabio De Francesco)

   - Include current frequency in the debug message printed by
     __cpufreq_driver_target() (Pengjie Zhang)

   - Refine stopped tick handling in the menu cpuidle governor and
     rearrange stopped tick handling in the teo cpuidle governor (Rafael
     Wysocki)

   - Add Panther Lake C-states table to the intel_idle driver (Artem
     Bityutskiy)

   - Clean up dead dependencies on CPU_IDLE in Kconfig (Julian Braha)

   - Simplify cpuidle_register_device() with guard() (Huisong Li)

   - Use performance level if available to distinguish between rates in
     OPP debugfs (Manivannan Sadhasivam)

   - Fix scoped_guard in dev_pm_opp_xlate_required_opp() (Viresh Kumar)

   - Return -ENODATA if the snapshot image is not loaded (Alberto
     Garcia)

   - Remove inclusion of crypto/hash.h from hibernate_64.c on x86 (Eric
     Biggers)

   - Clean up and rearrange the intel_rapl power capping driver to make
     the respective interface drivers (TPMI, MSR, and MMOI) hold their
     own settings and primitives and consolidate PL4 and PMU support
     flags into rapl_defaults (Kuppuswamy Sathyanarayanan)

   - Correct kernel-doc function parameter names in the power capping
     core code (Randy Dunlap)

   - Remove unneeded casting for HZ_PER_KHZ in devfreq (Andy Shevchenko)

   - Use _visible attribute to replace create/remove_sysfs_files() in
     devfreq (Pengjie Zhang)

   - Add Tegra114 support to activity monitor device in tegra30-devfreq
     as a preparation to upcoming EMC controller support (Svyatoslav
     Ryhel)

   - Fix mistakes in cpupower man pages, add the boost and epp options
     to the cpupower-frequency-info man page, and add the perf-bias
     option to the cpupower-info man page (Roberto Ricci)

   - Remove unnecessary extern declarations from getopt.h in arguments
     parsing functions in cpufreq-set, cpuidle-info, cpuidle-set,
     cpupower-info, and cpupower-set utilities (Kaushlendra Kumar)"

* tag 'pm-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (74 commits)
  cpufreq/amd-pstate: Add POWER_SUPPLY select for dynamic EPP
  cpupower: remove extern declarations in cmd functions
  cpuidle: Simplify cpuidle_register_device() with guard()
  PM / devfreq: tegra30-devfreq: add support for Tegra114
  PM / devfreq: use _visible attribute to replace create/remove_sysfs_files()
  PM / devfreq: Remove unneeded casting for HZ_PER_KHZ
  MAINTAINERS: amd-pstate: Step down as maintainer, add Prateek as reviewer
  cpufreq: Pass the policy to cpufreq_driver->adjust_perf()
  cpufreq/amd-pstate: Pass the policy to amd_pstate_update()
  cpufreq/amd-pstate-ut: Add a unit test for raw EPP
  cpufreq/amd-pstate: Add support for raw EPP writes
  cpufreq/amd-pstate: Add support for platform profile class
  cpufreq/amd-pstate: add kernel command line to override dynamic epp
  cpufreq/amd-pstate: Add dynamic energy performance preference
  Documentation: amd-pstate: fix dead links in the reference section
  cpufreq/amd-pstate: Cache the max frequency in cpudata
  Documentation/amd-pstate: Add documentation for amd_pstate_floor_{freq,count}
  Documentation/amd-pstate: List amd_pstate_prefcore_ranking sysfs file
  Documentation/amd-pstate: List amd_pstate_hw_prefcore sysfs file
  amd-pstate-ut: Add a testcase to validate the visibility of driver attributes
  ...
2026-04-13 19:47:52 -07:00
Rafael J. Wysocki 8e2308c1ae Merge branches 'acpica', 'acpi-osl' and 'acpi-tables'
Merge ACPICA updates, an ACPI OS service layer (OSL) update and
assorted updates related to parsing ACPI tables for 7.1-rc1:

 - Update maintainers information regarding ACPICA (Rafael Wysocki)

 - Replace strncpy() with strscpy_pad() in acpi_ut_safe_strncpy() (Kees
   Cook)

 - Trigger an ordered system power off after encountering a fatal error
   operator in AML (Armin Wolf)

 - Enable ACPI FPDT parsing on LoongArch (Xi Ruoyao)

 - Remove the temporary stop-gap acpi_pptt_cache_v1_full structure from
   the ACPI PPTT parser (Ben Horgan)

 - Add support for exposing ACPI FPDT subtables FBPT and S3PT (Nate
   DeSimone)

* acpica:
  ACPICA: Update maintainers information
  ACPICA: Replace strncpy() with strscpy_pad() in acpi_ut_safe_strncpy()

* acpi-osl:
  ACPI: OSL: Poweroff when encountering a fatal ACPI error

* acpi-tables:
  ACPI: tables: Enable FPDT on LoongArch
  Documentation: ABI: add FBPT and S3PT entries to sysfs-firmware-acpi
  ACPI: FPDT: expose FBPT and S3PT subtables via sysfs
  ACPI: PPTT: Remove duplicate structure, acpi_pptt_cache_v1_full
2026-04-09 21:19:34 +02:00
Li RongQingandJonathan Corbet 15d49089e5 Documentation/kernel-parameters: fix architecture alignment for pt, nopt, and nobypass
Commit ab0e7f2076 ("Documentation: Merge x86-specific boot options doc
into kernel-parameters.txt") introduced a formatting regression where
architecture tags were placed on separate lines with broken indentation.
This caused the 'nopt' [X86] parameter to appear as if it belonged to
the [PPC/POWERNV] section.

Furthermore, since the main 'iommu=' parameter heading already specifies
it is for [X86, EARLY], the subsequent standalone [X86] tags for 'pt',
'nopt', and the AMD GART options are redundant and clutter the
documentation.

Clean up the formatting by removing these redundant tags and properly
attributing the 'nobypass' option to [PPC/POWERNV].

Fixes: ab0e7f2076 ("Documentation: Merge x86-specific boot options doc into kernel-parameters.txt")
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260330105957.2271-1-lirongqing@baidu.com>
2026-04-09 08:36:52 -06:00
Marco ElverandAndrew Morton da735962d0 kfence: add kfence.fault parameter
Add kfence.fault parameter to control the behavior when a KFENCE error is
detected (similar in spirit to kasan.fault=<mode>).

The supported modes for kfence.fault=<mode> are:

  - report: print the error report and continue (default).
  - oops: print the error report and oops.
  - panic: print the error report and panic.

In particular, the 'oops' mode offers a trade-off between no mitigation
on report and panicking outright (if panic_on_oops is not set).

Link: https://lkml.kernel.org/r/20260225203639.3159463-1-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <kees@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:06 -07:00
Mario Limonciello (AMD) da8afb1c66 cpufreq/amd-pstate: add kernel command line to override dynamic epp
Add `amd_dynamic_epp=enable` and `amd_dynamic_epp=disable` to override
the kernel configuration option `CONFIG_X86_AMD_PSTATE_DYNAMIC_EPP`
locally.

Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
2026-04-02 11:29:11 -05:00
Breno LeitaoandTejun Heo 41e3ccca00 docs: workqueue: document WQ_AFFN_CACHE_SHARD affinity scope
Update kernel-parameters.txt and workqueue.rst to reflect the new
cache_shard affinity scope and the default change from cache to
cache_shard.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-01 10:24:18 -10:00
Will DeaconandMarc Zyngier 287c6981f1 KVM: arm64: Add some initial documentation for pKVM
Add some initial documentation for pKVM to help people understand what
is supported, the limitations of protected VMs when compared to
non-protected VMs and also what is left to do.

Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Tested-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://patch.msgid.link/20260330144841.26181-33-will@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
2026-03-30 16:58:09 +01:00
H. Peter AnvinandBorislav Petkov (AMD) ac66a73be0 x86/fred: Enable FRED by default
When FRED was added to the mainline kernel, it was set up as an explicit
opt-in due to the risk of regressions before hardware was available publicly.

Now, Panther Lake (Core Ultra 300 series) has been released, and benchmarking
by Phoronix has shown that it provides a significant performance benefit on
most workloads:

  https://www.phoronix.com/review/intel-fred-panther-lake

Accordingly, enable FRED by default if the CPU supports it. FRED can of
course still be disabled via the fred=off command line option.

Touch up Kconfig help too.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Sohil Mehta <sohil.mehta@intel.com>
Link: https://patch.msgid.link/20260325230151.1898287-2-hpa@zytor.com
2026-03-27 16:04:47 +01:00
Ingo Molnar f6472b1793 Merge tag 'v7.0-rc4' into timers/core, to resolve conflict
Resolve conflict between this change in the upstream kernel:

  4c652a4772 ("rseq: Mark rseq_arm_slice_extension_timer() __always_inline")

... and this pending change in timers/core:

  0e98eb1481 ("entry: Prepare for deferred hrtimer rearming")

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2026-03-21 08:02:36 +01:00
Thomas Gleixner 763aacf86f clocksource: Rewrite watchdog code completely
The clocksource watchdog code has over time reached the state of an
impenetrable maze of duct tape and staples. The original design, which was
made in the context of systems far smaller than today, is based on the
assumption that the to be monitored clocksource (TSC) can be trivially
compared against a known to be stable clocksource (HPET/ACPI-PM timer).

Over the years it turned out that this approach has major flaws:

  - Long delays between watchdog invocations can result in wrap arounds
    of the reference clocksource

  - Scalability of the reference clocksource readout can degrade on large
    multi-socket systems due to interconnect congestion

This was addressed with various heuristics which degraded the accuracy of
the watchdog to the point that it fails to detect actual TSC problems on
older hardware which exposes slow inter CPU drifts due to firmware
manipulating the TSC to hide SMI time.

To address this and bring back sanity to the watchdog, rewrite the code
completely with a different approach:

  1) Restrict the validation against a reference clocksource to the boot
     CPU, which is usually the CPU/Socket closest to the legacy block which
     contains the reference source (HPET/ACPI-PM timer). Validate that the
     reference readout is within a bound latency so that the actual
     comparison against the TSC stays within 500ppm as long as the clocks
     are stable.

  2) Compare the TSCs of the other CPUs in a round robin fashion against
     the boot CPU in the same way the TSC synchronization on CPU hotplug
     works. This still can suffer from delayed reaction of the remote CPU
     to the SMP function call and the latency of the control variable cache
     line. But this latency is not affecting correctness. It only affects
     the accuracy. With low contention the readout latency is in the low
     nanoseconds range, which detects even slight skews between CPUs. Under
     high contention this becomes obviously less accurate, but still
     detects slow skews reliably as it solely relies on subsequent readouts
     being monotonically increasing. It just can take slightly longer to
     detect the issue.

  3) Rewrite the watchdog test so it tests the various mechanisms one by
     one and validating the result against the expectation.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Daniel J Blueman <daniel@quora.org>
Reviewed-by: Jiri Wiesner <jwiesner@suse.de>
Reviewed-by: Daniel J Blueman <daniel@quora.org>
Link: https://patch.msgid.link/20260123231521.926490888@kernel.org
Link: https://patch.msgid.link/87h5qeomm5.ffs@tglx
2026-03-20 13:36:32 +01:00
Sohil MehtaandDave Hansen b36d1f53d9 x86/vsyscall: Disable LASS if vsyscall mode is set to EMULATE
The EMULATE mode of vsyscall maps the vsyscall page with a high kernel
address directly into user address space. Reading the vsyscall page in
EMULATE mode would cause LASS to trigger a #GP.

Fixing the LASS violation in EMULATE mode would require complex
instruction decoding because the resulting #GP does include the
necessary error information, and the vsyscall address is not
readily available in the RIP.

The EMULATE mode has been deprecated since 2022 and can only be enabled
using the command line parameter vsyscall=emulate. See commit
bf00745e77 ("x86/vsyscall: Remove CONFIG_LEGACY_VSYSCALL_EMULATE") for
details. At this point, no one is expected to be using this insecure
mode. The rare usages that need it obviously do not care about security.

Disable LASS when EMULATE mode is requested to avoid breaking legacy
user software. Also, update the vsyscall documentation to reflect this.
LASS will only be supported if vsyscall mode is set to XONLY (default)
or NONE.

Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Tested-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com>
Link: https://patch.msgid.link/20260309181029.398498-5-sohil.mehta@intel.com
2026-03-19 15:11:13 -07:00
Eric BiggersandMimi Zohar 7a60fe48af ima: remove buggy support for asynchronous hashes
IMA computes hashes using the crypto_shash or crypto_ahash API.  The
latter is used only when ima.ahash_minsize is set on the command line,
and its purpose is ostensibly to make the hash computation faster.

However, going off the CPU to a crypto engine and back again is actually
quite slow, especially compared with the acceleration that is built into
modern CPUs and the kernel now enables by default for most algorithms.
Typical performance results for SHA-256 on a modern platform can be
found at https://lore.kernel.org/linux-crypto/20250615184638.GA1480@sol/

Partly for this reason, several other kernel subsystems have already
dropped support for the crypto_ahash API.

The other problem with crypto_ahash is that bugs are also common, not
just in the underlying drivers, but also in the code using it, since it
is very difficult to use correctly.  Just from a quick review, here are
some of the bugs I noticed in IMA's ahash code:

- [Use after free] ima_alloc_atfm() isn't thread-safe and can trigger a
  use-after-free if multiple threads try to initialize the global
  ima_ahash_tfm at the same time.

- [Deadlock] If only one buffer is allocated and there is an error
  reading from the file, then ahash_wait() is executed twice, causing a
  deadlock in wait_for_completion().

- [Crash or incorrect hash computed] calc_buffer_ahash_atfm() is
  sometimes passed stack buffers which can be vmalloc addresses, but it
  puts them in a scatterlist assuming they are linear addresses.  This
  causes the hashing to be done on the wrong physical address.

- [Truncation to 32-bit length] ima_alloc_pages() incorrectly assumes an
  loff_t value fits in an unsigned long.  calc_buffer_ahash_atfm()
  incorrectly assumes that a loff_t value fits in an unsigned int.

So, not exactly a great track record so far, even disregarding driver
bugs which are an even larger problem.  Fortunately, in practice it's
unlikely that many users are actually setting the ima.ahash_minsize
kernel command-line parameter which enables this code.  However, given
that this code is almost certainly no longer useful (if it ever was),
let's just remove it instead of attempting to fix all these issues.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2026-03-17 18:53:49 -04:00
Linus Torvalds 69237f8c1f Merge tag 'usb-7.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
 "Here is a large chunk of USB driver fixes for 7.0-rc4. Included in
  here are:

   - usb gadget reverts due to reported issues, and then a follow-on fix
     to hopefully resolve the reported overall problem

   - xhci driver fixes

   - dwc3 driver fixes

   - usb core "killable" bulk message api addition to fix a usbtmc
     driver bug where userspace could hang the driver for forever

   - small USB driver fixes for reported issues

   - new usb device quirks

  All except the last USB device quirk change have been in linux-next
  with no reported issues. That one came in too late, and is 'obviously
  correct' :)"

* tag 'usb-7.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (35 commits)
  USB: ezcap401 needs USB_QUIRK_NO_BOS to function on 10gbs usb speed
  usb: roles: get usb role switch from parent only for usb-b-connector
  Revert "tcpm: allow looking for role_sw device in the main node"
  usb: gadget: f_ncm: Fix net_device lifecycle with device_move
  Revert "usb: gadget: u_ether: add gether_opts for config caching"
  Revert "usb: gadget: u_ether: use <linux/hex.h> header file"
  Revert "usb: gadget: u_ether: Add auto-cleanup helper for freeing net_device"
  Revert "usb: gadget: f_ncm: align net_device lifecycle with bind/unbind"
  Revert "usb: legacy: ncm: Fix NPE in gncm_bind"
  Revert "usb: gadget: f_ncm: Fix atomic context locking issue"
  usb: typec: altmode/displayport: set displayport signaling rate in configure message
  usb: dwc3: pci: add support for the Intel Nova Lake -H
  usb/core/quirks: Add Huawei ME906S-device to wakeup quirk
  usb: gadget: uvc: fix interval_duration calculation
  xhci: Fix NULL pointer dereference when reading portli debugfs files
  usb: xhci: Prevent interrupt storm on host controller error (HCE)
  usb: xhci: Fix memory leak in xhci_disable_slot()
  usb: class: cdc-wdm: fix reordering issue in read code path
  usb: renesas_usbhs: fix use-after-free in ISR during device removal
  usb: cdc-acm: Restore CAP_BRK functionnality to CH343
  ...
2026-03-14 09:43:12 -07:00
Rafael J. Wysocki f862f29196 Merge back ACPI OS services layer (OSL) material for 7.1 2026-03-12 21:16:46 +01:00