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5 daysMerge tag 'x86_core_for_v6.18_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more x86 updates from Borislav Petkov: - Remove a bunch of asm implementing condition flags testing in KVM's emulator in favor of int3_emulate_jcc() which is written in C - Replace KVM fastops with C-based stubs which avoids problems with the fastop infra related to latter not adhering to the C ABI due to their special calling convention and, more importantly, bypassing compiler control-flow integrity checking because they're written in asm - Remove wrongly used static branches and other ugliness accumulated over time in hyperv's hypercall implementation with a proper static function call to the correct hypervisor call variant - Add some fixes and modifications to allow running FRED-enabled kernels in KVM even on non-FRED hardware - Add kCFI improvements like validating indirect calls and prepare for enabling kCFI with GCC. Add cmdline params documentation and other code cleanups - Use the single-byte 0xd6 insn as the official #UD single-byte undefined opcode instruction as agreed upon by both x86 vendors - Other smaller cleanups and touchups all over the place * tag 'x86_core_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) x86,retpoline: Optimize patch_retpoline() x86,ibt: Use UDB instead of 0xEA x86/cfi: Remove __noinitretpoline and __noretpoline x86/cfi: Add "debug" option to "cfi=" bootparam x86/cfi: Standardize on common "CFI:" prefix for CFI reports x86/cfi: Document the "cfi=" bootparam options x86/traps: Clarify KCFI instruction layout compiler_types.h: Move __nocfi out of compiler-specific header objtool: Validate kCFI calls x86/fred: KVM: VMX: Always use FRED for IRQs when CONFIG_X86_FRED=y x86/fred: Play nice with invoking asm_fred_entry_from_kvm() on non-FRED hardware x86/fred: Install system vector handlers even if FRED isn't fully enabled x86/hyperv: Use direct call to hypercall-page x86/hyperv: Clean up hv_do_hypercall() KVM: x86: Remove fastops KVM: x86: Convert em_salc() to C KVM: x86: Introduce EM_ASM_3WCL KVM: x86: Introduce EM_ASM_1SRC2 KVM: x86: Introduce EM_ASM_2CL KVM: x86: Introduce EM_ASM_2W ...
10 daysMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull x86 kvm updates from Paolo Bonzini: "Generic: - Rework almost all of KVM's exports to expose symbols only to KVM's x86 vendor modules (kvm-{amd,intel}.ko and PPC's kvm-{pr,hv}.ko x86: - Rework almost all of KVM x86's exports to expose symbols only to KVM's vendor modules, i.e. to kvm-{amd,intel}.ko - Add support for virtualizing Control-flow Enforcement Technology (CET) on Intel (Shadow Stacks and Indirect Branch Tracking) and AMD (Shadow Stacks). It is worth noting that while SHSTK and IBT can be enabled separately in CPUID, it is not really possible to virtualize them separately. Therefore, Intel processors will really allow both SHSTK and IBT under the hood if either is made visible in the guest's CPUID. The alternative would be to intercept XSAVES/XRSTORS, which is not feasible for performance reasons - Fix a variety of fuzzing WARNs all caused by checking L1 intercepts when completing userspace I/O. KVM has already committed to allowing L2 to to perform I/O at that point - Emulate PERF_CNTR_GLOBAL_STATUS_SET for PerfMonV2 guests, as the MSR is supposed to exist for v2 PMUs - Allow Centaur CPU leaves (base 0xC000_0000) for Zhaoxin CPUs - Add support for the immediate forms of RDMSR and WRMSRNS, sans full emulator support (KVM should never need to emulate the MSRs outside of forced emulation and other contrived testing scenarios) - Clean up the MSR APIs in preparation for CET and FRED virtualization, as well as mediated vPMU support - Clean up a pile of PMU code in anticipation of adding support for mediated vPMUs - Reject in-kernel IOAPIC/PIT for TDX VMs, as KVM can't obtain EOI vmexits needed to faithfully emulate an I/O APIC for such guests - Many cleanups and minor fixes - Recover possible NX huge pages within the TDP MMU under read lock to reduce guest jitter when restoring NX huge pages - Return -EAGAIN during prefault if userspace concurrently deletes/moves the relevant memslot, to fix an issue where prefaulting could deadlock with the memslot update x86 (AMD): - Enable AVIC by default for Zen4+ if x2AVIC (and other prereqs) is supported - Require a minimum GHCB version of 2 when starting SEV-SNP guests via KVM_SEV_INIT2 so that invalid GHCB versions result in immediate errors instead of latent guest failures - Add support for SEV-SNP's CipherText Hiding, an opt-in feature that prevents unauthorized CPU accesses from reading the ciphertext of SNP guest private memory, e.g. to attempt an offline attack. This feature splits the shared SEV-ES/SEV-SNP ASID space into separate ranges for SEV-ES and SEV-SNP guests, therefore a new module parameter is needed to control the number of ASIDs that can be used for VMs with CipherText Hiding vs. how many can be used to run SEV-ES guests - Add support for Secure TSC for SEV-SNP guests, which prevents the untrusted host from tampering with the guest's TSC frequency, while still allowing the the VMM to configure the guest's TSC frequency prior to launch - Validate the XCR0 provided by the guest (via the GHCB) to avoid bugs resulting from bogus XCR0 values - Save an SEV guest's policy if and only if LAUNCH_START fully succeeds to avoid leaving behind stale state (thankfully not consumed in KVM) - Explicitly reject non-positive effective lengths during SNP's LAUNCH_UPDATE instead of subtly relying on guest_memfd to deal with them - Reload the pre-VMRUN TSC_AUX on #VMEXIT for SEV-ES guests, not the host's desired TSC_AUX, to fix a bug where KVM was keeping a different vCPU's TSC_AUX in the host MSR until return to userspace KVM (Intel): - Preparation for FRED support - Don't retry in TDX's anti-zero-step mitigation if the target memslot is invalid, i.e. is being deleted or moved, to fix a deadlock scenario similar to the aforementioned prefaulting case - Misc bugfixes and minor cleanups" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (142 commits) KVM: x86: Export KVM-internal symbols for sub-modules only KVM: x86: Drop pointless exports of kvm_arch_xxx() hooks KVM: x86: Move kvm_intr_is_single_vcpu() to lapic.c KVM: Export KVM-internal symbols for sub-modules only KVM: s390/vfio-ap: Use kvm_is_gpa_in_memslot() instead of open coded equivalent KVM: VMX: Make CR4.CET a guest owned bit KVM: selftests: Verify MSRs are (not) in save/restore list when (un)supported KVM: selftests: Add coverage for KVM-defined registers in MSRs test KVM: selftests: Add KVM_{G,S}ET_ONE_REG coverage to MSRs test KVM: selftests: Extend MSRs test to validate vCPUs without supported features KVM: selftests: Add support for MSR_IA32_{S,U}_CET to MSRs test KVM: selftests: Add an MSR test to exercise guest/host and read/write KVM: x86: Define AMD's #HV, #VC, and #SX exception vectors KVM: x86: Define Control Protection Exception (#CP) vector KVM: x86: Add human friendly formatting for #XM, and #VE KVM: SVM: Enable shadow stack virtualization for SVM KVM: SEV: Synchronize MSR_IA32_XSS from the GHCB when it's valid KVM: SVM: Pass through shadow stack MSRs as appropriate KVM: SVM: Update dump_vmcb with shadow stack save area additions KVM: nSVM: Save/load CET Shadow Stack state to/from vmcb12/vmcb02 ...
12 daysMerge tag 'docs-6.18' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a relatively busy cycle in docsland, with changes all over: - Bring the kernel memory-model docs into the Sphinx build in the "literal include" mode. - Lots of build-infrastructure work, further cleaning up long-term kernel-doc technical debt. The sphinx-pre-install tool has been converted to Python and updated for current systems. - A new tool to detect when documents have been moved and generate HTML redirects; this can be used on kernel.org (or any other site hosting the rendered docs) to avoid breaking links. - Automated processing of the YAML files describing the netlink protocol. - A significant update of the maintainer's PGP guide. ... and a seemingly endless series of typo fixes, build-problem fixes, etc" * tag 'docs-6.18' of git://git.lwn.net/linux: (193 commits) Documentation/features: Update feature lists for 6.17-rc7 docs: remove cdomain.py Documentation/process: submitting-patches: fix typo in "were do" docs: dev-tools/lkmm: Fix typo of missing file extension Documentation: trace: histogram: Convert ftrace docs cross-reference Documentation: trace: histogram-design: Wrap introductory note in note:: directive Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram Documentation: trace: histogram-design: Trim trailing vertices in diagram explanation text Documentation: trace: histogram: Fix histogram trigger subsection number order docs: driver-api: fix spelling of "buses". Documentation: fbcon: Use admonition directives Documentation: fbcon: Reindent 8th step of attach/detach/unload Documentation: fbcon: Add boot options and attach/detach/unload section headings docs: filesystems: sysfs: add remaining top level sysfs directory descriptions docs: filesystems: sysfs: clarify symlink destinations in dev and bus/devices descriptions docs: filesystems: sysfs: remove top level sysfs net directory docs: maintainer: Fix ambiguous subheading formatting docs: kdoc: a few more dump_typedef() tweaks docs: kdoc: remove redundant comment stripping in dump_typedef() docs: kdoc: remove some dead code in dump_typedef() ...
13 daysMerge tag 'mm-nonmm-stable-2025-10-02-15-29' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - "ida: Remove the ida_simple_xxx() API" from Christophe Jaillet completes the removal of this legacy IDR API - "panic: introduce panic status function family" from Jinchao Wang provides a number of cleanups to the panic code and its various helpers, which were rather ad-hoc and scattered all over the place - "tools/delaytop: implement real-time keyboard interaction support" from Fan Yu adds a few nice user-facing usability changes to the delaytop monitoring tool - "efi: Fix EFI boot with kexec handover (KHO)" from Evangelos Petrongonas fixes a panic which was happening with the combination of EFI and KHO - "Squashfs: performance improvement and a sanity check" from Phillip Lougher teaches squashfs's lseek() about SEEK_DATA/SEEK_HOLE. A mere 150x speedup was measured for a well-chosen microbenchmark - plus another 50-odd singleton patches all over the place * tag 'mm-nonmm-stable-2025-10-02-15-29' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (75 commits) Squashfs: reject negative file sizes in squashfs_read_inode() kallsyms: use kmalloc_array() instead of kmalloc() MAINTAINERS: update Sibi Sankar's email address Squashfs: add SEEK_DATA/SEEK_HOLE support Squashfs: add additional inode sanity checking lib/genalloc: fix device leak in of_gen_pool_get() panic: remove CONFIG_PANIC_ON_OOPS_VALUE ocfs2: fix double free in user_cluster_connect() checkpatch: suppress strscpy warnings for userspace tools cramfs: fix incorrect physical page address calculation kernel: prevent prctl(PR_SET_PDEATHSIG) from racing with parent process exit Squashfs: fix uninit-value in squashfs_get_parent kho: only fill kimage if KHO is finalized ocfs2: avoid extra calls to strlen() after ocfs2_sprintf_system_inode_name() kernel/sys.c: fix the racy usage of task_lock(tsk->group_leader) in sys_prlimit64() paths sched/task.h: fix the wrong comment on task_lock() nesting with tasklist_lock coccinelle: platform_no_drv_owner: handle also built-in drivers coccinelle: of_table: handle SPI device ID tables lib/decompress: use designated initializers for struct compress_format efi: support booting with kexec handover (KHO) ...
2025-09-30Merge tag 'irq-core-2025-09-29' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq core updates from Thomas Gleixner: "A set of updates for the interrupt core subsystem: - Introduce irq_chip_[startup|shutdown]_parent() to prepare for addressing a few short comings in the PCI/MSI interrupt subsystem. It allows to utilize the interrupt chip startup/shutdown callbacks for initializing the interrupt chip hierarchy properly on certain RISCV implementations and provides a mechanism to reduce the overhead of masking and unmasking PCI/MSI interrupts during operation when the underlying MSI provider can mask the interrupt. The actual usage comes with the interrupt driver pull request. - Add generic error handling for devm_request_*_irq() This allows to remove the zoo of random error printk's all over the usage sites. - Add a mechanism to warn about long-running interrupt handlers Long running interrupt handlers can introduce latencies and tracking them down is a tedious task. The tracking has to be enabled with a threshold on the kernel command line and utilizes a static branch to remove the overhead when disabled. - Update and extend the selftests which validate the CPU hotplug interrupt migration logic - Allow dropping the per CPU softirq lock on PREEMPT_RT kernels, which causes contention and latencies all over the place. The serialization requirements have been pushed down into the actual affected usage sites already. - The usual small cleanups and improvements" * tag 'irq-core-2025-09-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: softirq: Allow to drop the softirq-BKL lock on PREEMPT_RT softirq: Provide a handshake for canceling tasklets via polling genirq/test: Ensure CPU 1 is online for hotplug test genirq/test: Drop CONFIG_GENERIC_IRQ_MIGRATION assumptions genirq/test: Depend on SPARSE_IRQ genirq/test: Fail early if interrupt request fails genirq/test: Factor out fake-virq setup genirq/test: Select IRQ_DOMAIN genirq/test: Fix depth tests on architectures with NOREQUEST by default. genirq: Add support for warning on long-running interrupt handlers genirq/devres: Add error handling in devm_request_*_irq() genirq: Add irq_chip_(startup/shutdown)_parent() genirq: Remove GENERIC_IRQ_LEGACY
2025-09-30Merge tag 'x86_cache_for_v6.18_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 on AMD for assigning QoS bandwidth counters to resources (RMIDs) with the ability for those resources to be tracked by the counters as long as they're assigned to them. Previously, due to hw limitations, bandwidth counts from untracked resources would get lost when those resources are not tracked. Refactor the code and user interfaces to be able to also support other, similar features on ARM, for example" * tag 'x86_cache_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits) fs/resctrl: Fix counter auto-assignment on mkdir with mbm_event enabled MAINTAINERS: resctrl: Add myself as reviewer x86/resctrl: Configure mbm_event mode if supported fs/resctrl: Introduce the interface to switch between monitor modes fs/resctrl: Disable BMEC event configuration when mbm_event mode is enabled fs/resctrl: Introduce the interface to modify assignments in a group fs/resctrl: Introduce mbm_L3_assignments to list assignments in a group fs/resctrl: Auto assign counters on mkdir and clean up on group removal fs/resctrl: Introduce mbm_assign_on_mkdir to enable assignments on mkdir fs/resctrl: Provide interface to update the event configurations fs/resctrl: Add event configuration directory under info/L3_MON/ fs/resctrl: Support counter read/reset with mbm_event assignment mode x86/resctrl: Implement resctrl_arch_reset_cntr() and resctrl_arch_cntr_read() x86/resctrl: Refactor resctrl_arch_rmid_read() fs/resctrl: Introduce counter ID read, reset calls in mbm_event mode fs/resctrl: Pass struct rdtgroup instead of individual members fs/resctrl: Add the functionality to unassign MBM events fs/resctrl: Add the functionality to assign MBM events x86,fs/resctrl: Implement resctrl_arch_config_cntr() to assign a counter with ABMC fs/resctrl: Introduce event configuration field in struct mon_evt ...
2025-09-30Merge tag 'x86_microcode_for_v6.18_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loading updates from Borislav Petkov: - Add infrastructure to be able to debug the microcode loader in a guest - Refresh Intel old microcode revisions * tag 'x86_microcode_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode: Add microcode loader debugging functionality x86/microcode: Add microcode= cmdline parsing x86/microcode/intel: Refresh the revisions that determine old_microcode
2025-09-30Merge tag 'kvm-x86-ciphertext-6.18' of https://github.com/kvm-x86/linux into ↵Paolo Bonzini
HEAD KVM SEV-SNP CipherText Hiding support for 6.18 Add support for SEV-SNP's CipherText Hiding, an opt-in feature that prevents unauthorized CPU accesses from reading the ciphertext of SNP guest private memory, e.g. to attempt an offline attack. Instead of ciphertext, the CPU will always read back all FFs when CipherText Hiding is enabled. Add new module parameter to the KVM module to enable CipherText Hiding and control the number of ASIDs that can be used for VMs with CipherText Hiding, which is in effect the number of SNP VMs. When CipherText Hiding is enabled, the shared SEV-ES/SEV-SNP ASID space is split into separate ranges for SEV-ES and SEV-SNP guests, i.e. ASIDs that can be used for CipherText Hiding cannot be used to run SEV-ES guests.
2025-09-29Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "There's good stuff across the board, including some nice mm improvements for CPUs with the 'noabort' BBML2 feature and a clever patch to allow ptdump to play nicely with block mappings in the vmalloc area. Confidential computing: - Add support for accepting secrets from firmware (e.g. ACPI CCEL) and mapping them with appropriate attributes. CPU features: - Advertise atomic floating-point instructions to userspace - Extend Spectre workarounds to cover additional Arm CPU variants - Extend list of CPUs that support break-before-make level 2 and guarantee not to generate TLB conflict aborts for changes of mapping granularity (BBML2_NOABORT) - Add GCS support to our uprobes implementation. Documentation: - Remove bogus SME documentation concerning register state when entering/exiting streaming mode. Entry code: - Switch over to the generic IRQ entry code (GENERIC_IRQ_ENTRY) - Micro-optimise syscall entry path with a compiler branch hint. Memory management: - Enable huge mappings in vmalloc space even when kernel page-table dumping is enabled - Tidy up the types used in our early MMU setup code - Rework rodata= for closer parity with the behaviour on x86 - For CPUs implementing BBML2_NOABORT, utilise block mappings in the linear map even when rodata= applies to virtual aliases - Don't re-allocate the virtual region between '_text' and '_stext', as doing so confused tools parsing /proc/vmcore. Miscellaneous: - Clean-up Kconfig menuconfig text for architecture features - Avoid redundant bitmap_empty() during determination of supported SME vector lengths - Re-enable warnings when building the 32-bit vDSO object - Avoid breaking our eggs at the wrong end. Perf and PMUs: - Support for v3 of the Hisilicon L3C PMU - Support for Hisilicon's MN and NoC PMUs - Support for Fujitsu's Uncore PMU - Support for SPE's extended event filtering feature - Preparatory work to enable data source filtering in SPE - Support for multiple lanes in the DWC PCIe PMU - Support for i.MX94 in the IMX DDR PMU driver - MAINTAINERS update (Thank you, Yicong) - Minor driver fixes (PERF_IDX2OFF() overflow, CMN register offsets). Selftests: - Add basic LSFE check to the existing hwcaps test - Support nolibc in GCS tests - Extend SVE ptrace test to pass unsupported regsets and invalid vector lengths - Minor cleanups (typos, cosmetic changes). System registers: - Fix ID_PFR1_EL1 definition - Fix incorrect signedness of some fields in ID_AA64MMFR4_EL1 - Sync TCR_EL1 definition with the latest Arm ARM (L.b) - Be stricter about the input fed into our AWK sysreg generator script - Typo fixes and removal of redundant definitions. ACPI, EFI and PSCI: - Decouple Arm's "Software Delegated Exception Interface" (SDEI) support from the ACPI GHES code so that it can be used by platforms booted with device-tree - Remove unnecessary per-CPU tracking of the FPSIMD state across EFI runtime calls - Fix a node refcount imbalance in the PSCI device-tree code. CPU Features: - Ensure register sanitisation is applied to fields in ID_AA64MMFR4 - Expose AIDR_EL1 to userspace via sysfs, primarily so that KVM guests can reliably query the underlying CPU types from the VMM - Re-enabling of SME support (CONFIG_ARM64_SME) as a result of fixes to our context-switching, signal handling and ptrace code" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (93 commits) arm64: cpufeature: Remove duplicate asm/mmu.h header arm64: Kconfig: Make CPU_BIG_ENDIAN depend on BROKEN perf/dwc_pcie: Fix use of uninitialized variable arm/syscalls: mark syscall invocation as likely in invoke_syscall Documentation: hisi-pmu: Add introduction to HiSilicon V3 PMU Documentation: hisi-pmu: Fix of minor format error drivers/perf: hisi: Add support for L3C PMU v3 drivers/perf: hisi: Refactor the event configuration of L3C PMU drivers/perf: hisi: Extend the field of tt_core drivers/perf: hisi: Extract the event filter check of L3C PMU drivers/perf: hisi: Simplify the probe process of each L3C PMU version drivers/perf: hisi: Export hisi_uncore_pmu_isr() drivers/perf: hisi: Relax the event ID check in the framework perf: Fujitsu: Add the Uncore PMU driver arm64: map [_text, _stext) virtual address range non-executable+read-only arm64/sysreg: Update TCR_EL1 register arm64: Enable vmalloc-huge with ptdump arm64: cpufeature: add Neoverse-V3AE to BBML2 allow list arm64: errata: Apply workarounds for Neoverse-V3AE arm64: cputype: Add Neoverse-V3AE definitions ...
2025-09-29Merge tag 'vfs-6.18-rc1.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull misc vfs updates from Christian Brauner: "This contains the usual selections of misc updates for this cycle. Features: - Add "initramfs_options" parameter to set initramfs mount options. This allows to add specific mount options to the rootfs to e.g., limit the memory size - Add RWF_NOSIGNAL flag for pwritev2() Add RWF_NOSIGNAL flag for pwritev2. This flag prevents the SIGPIPE signal from being raised when writing on disconnected pipes or sockets. The flag is handled directly by the pipe filesystem and converted to the existing MSG_NOSIGNAL flag for sockets - Allow to pass pid namespace as procfs mount option Ever since the introduction of pid namespaces, procfs has had very implicit behaviour surrounding them (the pidns used by a procfs mount is auto-selected based on the mounting process's active pidns, and the pidns itself is basically hidden once the mount has been constructed) This implicit behaviour has historically meant that userspace was required to do some special dances in order to configure the pidns of a procfs mount as desired. Examples include: * In order to bypass the mnt_too_revealing() check, Kubernetes creates a procfs mount from an empty pidns so that user namespaced containers can be nested (without this, the nested containers would fail to mount procfs) But this requires forking off a helper process because you cannot just one-shot this using mount(2) * Container runtimes in general need to fork into a container before configuring its mounts, which can lead to security issues in the case of shared-pidns containers (a privileged process in the pidns can interact with your container runtime process) While SUID_DUMP_DISABLE and user namespaces make this less of an issue, the strict need for this due to a minor uAPI wart is kind of unfortunate Things would be much easier if there was a way for userspace to just specify the pidns they want. So this pull request contains changes to implement a new "pidns" argument which can be set using fsconfig(2): fsconfig(procfd, FSCONFIG_SET_FD, "pidns", NULL, nsfd); fsconfig(procfd, FSCONFIG_SET_STRING, "pidns", "/proc/self/ns/pid", 0); or classic mount(2) / mount(8): // mount -t proc -o pidns=/proc/self/ns/pid proc /tmp/proc mount("proc", "/tmp/proc", "proc", MS_..., "pidns=/proc/self/ns/pid"); Cleanups: - Remove the last references to EXPORT_OP_ASYNC_LOCK - Make file_remove_privs_flags() static - Remove redundant __GFP_NOWARN when GFP_NOWAIT is used - Use try_cmpxchg() in start_dir_add() - Use try_cmpxchg() in sb_init_done_wq() - Replace offsetof() with struct_size() in ioctl_file_dedupe_range() - Remove vfs_ioctl() export - Replace rwlock() with spinlock in epoll code as rwlock causes priority inversion on preempt rt kernels - Make ns_entries in fs/proc/namespaces const - Use a switch() statement() in init_special_inode() just like we do in may_open() - Use struct_size() in dir_add() in the initramfs code - Use str_plural() in rd_load_image() - Replace strcpy() with strscpy() in find_link() - Rename generic_delete_inode() to inode_just_drop() and generic_drop_inode() to inode_generic_drop() - Remove unused arguments from fcntl_{g,s}et_rw_hint() Fixes: - Document @name parameter for name_contains_dotdot() helper - Fix spelling mistake - Always return zero from replace_fd() instead of the file descriptor number - Limit the size for copy_file_range() in compat mode to prevent a signed overflow - Fix debugfs mount options not being applied - Verify the inode mode when loading it from disk in minixfs - Verify the inode mode when loading it from disk in cramfs - Don't trigger automounts with RESOLVE_NO_XDEV If openat2() was called with RESOLVE_NO_XDEV it didn't traverse through automounts, but could still trigger them - Add FL_RECLAIM flag to show_fl_flags() macro so it appears in tracepoints - Fix unused variable warning in rd_load_image() on s390 - Make INITRAMFS_PRESERVE_MTIME depend on BLK_DEV_INITRD - Use ns_capable_noaudit() when determining net sysctl permissions - Don't call path_put() under namespace semaphore in listmount() and statmount()" * tag 'vfs-6.18-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (38 commits) fcntl: trim arguments listmount: don't call path_put() under namespace semaphore statmount: don't call path_put() under namespace semaphore pid: use ns_capable_noaudit() when determining net sysctl permissions fs: rename generic_delete_inode() and generic_drop_inode() init: INITRAMFS_PRESERVE_MTIME should depend on BLK_DEV_INITRD initramfs: Replace strcpy() with strscpy() in find_link() initrd: Use str_plural() in rd_load_image() initramfs: Use struct_size() helper to improve dir_add() initrd: Fix unused variable warning in rd_load_image() on s390 fs: use the switch statement in init_special_inode() fs/proc/namespaces: make ns_entries const filelock: add FL_RECLAIM to show_fl_flags() macro eventpoll: Replace rwlock with spinlock selftests/proc: add tests for new pidns APIs procfs: add "pidns" mount option pidns: move is-ancestor logic to helper openat2: don't trigger automounts with RESOLVE_NO_XDEV namei: move cross-device check to __traverse_mounts namei: remove LOOKUP_NO_XDEV check from handle_mounts ...
2025-09-16arm64: mm: Rework the 'rodata=' optionsHuang Shijie
As per admin guide documentation, "rodata=on" should be the default on platforms. Documentation/admin-guide/kernel-parameters.txt describes these options as rodata= [KNL,EARLY] on Mark read-only kernel memory as read-only (default). off Leave read-only kernel memory writable for debugging. full Mark read-only kernel memory and aliases as read-only [arm64] But on arm64 platform, RODATA_FULL_DEFAULT_ENABLED is enabled by default, so "rodata=full" is the default instead. For parity with other architectures, namely x86, rework 'rodata=on' to match the current "full" behaviour and replace 'rodata=full' with a new 'rodata=noalias' option which retains writable aliases in the direct map for memory regions outside of the kernel image. Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2025-09-15KVM: SEV: Add SEV-SNP CipherTextHiding supportAshish Kalra
Ciphertext hiding prevents host accesses from reading the ciphertext of SNP guest private memory. Instead of reading ciphertext, the host reads will see constant default values (0xff). The SEV ASID space is split into SEV and SEV-ES/SEV-SNP ASID ranges. Enabling ciphertext hiding further splits the SEV-ES/SEV-SNP ASID space into separate ASID ranges for SEV-ES and SEV-SNP guests. Add a new off-by-default kvm-amd module parameter to enable ciphertext hiding and allow the admin to configure the SEV-ES and SEV-SNP ASID ranges. Simply cap the maximum SEV-SNP ASID as appropriate, i.e. don't reject loading KVM or disable ciphertest hiding for a too-big value, as KVM's general approach for module params is to sanitize inputs based on hardware/kernel support, not burn the world down. This also allows the admin to use -1u to assign all SEV-ES/SNP ASIDs to SNP without needing dedicated handling in KVM. Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> Co-developed-by: Sean Christopherson <seanjc@google.com> Link: https://lore.kernel.org/r/95abc49edfde36d4fb791570ea2a4be6ad95fd0d.1755721927.git.ashish.kalra@amd.com Signed-off-by: Sean Christopherson <seanjc@google.com>
2025-09-15x86/resctrl: Add ABMC feature in the command line optionsBabu Moger
Add a kernel command-line parameter to enable or disable the exposure of the ABMC (Assignable Bandwidth Monitoring Counters) 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://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-13panic: refine the document for 'panic_print'Feng Tang
User reported current document about SYS_INFO_PANIC_CONSOLE_REPLAY is confusing, that people could expect all user space console messages to be replayed. Specify that only 'kernel' messages will be replayed to solve the confusion. Link: https://lkml.kernel.org/r/20250825025701.81921-3-feng.tang@linux.alibaba.com Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com> Reported-by: Askar Safin <safinaskar@zohomail.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-04x86/cfi: Add "debug" option to "cfi=" bootparamKees Cook
Add "debug" option for "cfi=" bootparam to get details on early CFI initialization steps so future Kees can find breakage easier. Signed-off-by: Kees Cook <kees@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20250904034656.3670313-5-kees@kernel.org
2025-09-04x86/cfi: Document the "cfi=" bootparam optionsKees Cook
The kernel-parameters.txt didn't have a section for the cfi= options. Add it. Signed-off-by: Kees Cook <kees@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20250904034656.3670313-3-kees@kernel.org
2025-09-04x86/microcode: Add microcode loader debugging functionalityBorislav Petkov (AMD)
Instead of adding ad-hoc debugging glue to the microcode loader each time I need it, add debugging functionality which is not built by default. Simulate all patch handling the loader does except the actual loading of the microcode patch into the hardware. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250820135043.19048-3-bp@kernel.org
2025-09-04x86/microcode: Add microcode= cmdline parsingBorislav Petkov (AMD)
Add a "microcode=" command line argument after which all options can be passed in a comma-separated list. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Sohil Mehta <sohil.mehta@intel.com> Reviewed-by: Chang S. Bae <chang.seok.bae@intel.com> Link: https://lore.kernel.org/20250820135043.19048-2-bp@kernel.org
2025-09-03genirq: Add support for warning on long-running interrupt handlersWladislav Wiebe
Introduce a mechanism to detect and warn about prolonged interrupt handlers. With a new command-line parameter (irqhandler.duration_warn_us=), users can configure the duration threshold in microseconds when a warning in such format should be emitted: "[CPU14] long duration of IRQ[159:bad_irq_handler [long_irq]], took: 1330 us" The implementation uses local_clock() to measure the execution duration of the generic IRQ per-CPU event handler. Signed-off-by: Wladislav Wiebe <wladislav.wiebe@nokia.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Link: https://lore.kernel.org/all/20250804093525.851-1-wladislav.wiebe@nokia.com
2025-08-21fs: Add 'initramfs_options' to set initramfs mount optionsLichen Liu
When CONFIG_TMPFS is enabled, the initial root filesystem is a tmpfs. By default, a tmpfs mount is limited to using 50% of the available RAM for its content. This can be problematic in memory-constrained environments, particularly during a kdump capture. In a kdump scenario, the capture kernel boots with a limited amount of memory specified by the 'crashkernel' parameter. If the initramfs is large, it may fail to unpack into the tmpfs rootfs due to insufficient space. This is because to get X MB of usable space in tmpfs, 2*X MB of memory must be available for the mount. This leads to an OOM failure during the early boot process, preventing a successful crash dump. This patch introduces a new kernel command-line parameter, initramfs_options, which allows passing specific mount options directly to the rootfs when it is first mounted. This gives users control over the rootfs behavior. For example, a user can now specify initramfs_options=size=75% to allow the tmpfs to use up to 75% of the available memory. This can significantly reduce the memory pressure for kdump. Consider a practical example: To unpack a 48MB initramfs, the tmpfs needs 48MB of usable space. With the default 50% limit, this requires a memory pool of 96MB to be available for the tmpfs mount. The total memory requirement is therefore approximately: 16MB (vmlinuz) + 48MB (loaded initramfs) + 48MB (unpacked kernel) + 96MB (for tmpfs) + 12MB (runtime overhead) ≈ 220MB. By using initramfs_options=size=75%, the memory pool required for the 48MB tmpfs is reduced to 48MB / 0.75 = 64MB. This reduces the total memory requirement by 32MB (96MB - 64MB), allowing the kdump to succeed with a smaller crashkernel size, such as 192MB. An alternative approach of reusing the existing rootflags parameter was considered. However, a new, dedicated initramfs_options parameter was chosen to avoid altering the current behavior of rootflags (which applies to the final root filesystem) and to prevent any potential regressions. Also add documentation for the new kernel parameter "initramfs_options" This approach is inspired by prior discussions and patches on the topic. Ref: https://www.lightofdawn.org/blog/?viewDetailed=00128 Ref: https://landley.net/notes-2015.html#01-01-2015 Ref: https://lkml.org/lkml/2021/6/29/783 Ref: https://www.kernel.org/doc/html/latest/filesystems/ramfs-rootfs-initramfs.html#what-is-rootfs Signed-off-by: Lichen Liu <lichliu@redhat.com> Link: https://lore.kernel.org/20250815121459.3391223-1-lichliu@redhat.com Tested-by: Rob Landley <rob@landley.net> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-18Documentation: Fix admin-guide typosBjorn Helgaas
Fix typos. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250813200526.290420-4-helgaas@kernel.org
2025-08-14x86/vmscape: Enable the mitigationPawan Gupta
Enable the previously added mitigation for VMscape. Add the cmdline vmscape={off|ibpb|force} and sysfs reporting. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
2025-08-04Merge tag 'printk-for-6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: - Add new "hash_pointers=[auto|always|never]" boot parameter to force the hashing even with "slab_debug" enabled - Allow to stop CPU, after losing nbcon console ownership during panic(), even without proper NMI - Allow to use the printk kthread immediately even for the 1st registered nbcon - Compiler warning removal * tag 'printk-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printk: nbcon: Allow reacquire during panic printk: Allow to use the printk kthread immediately even for 1st nbcon slab: Decouple slab_debug and no_hash_pointers vsprintf: Use __diag macros to disable '-Wsuggest-attribute=format' compiler-gcc.h: Introduce __diag_GCC_all
2025-08-03Merge tag 'mm-nonmm-stable-2025-08-03-12-47' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: "Significant patch series in this pull request: - "squashfs: Remove page->mapping references" (Matthew Wilcox) gets us closer to being able to remove page->mapping - "relayfs: misc changes" (Jason Xing) does some maintenance and minor feature addition work in relayfs - "kdump: crashkernel reservation from CMA" (Jiri Bohac) switches us from static preallocation of the kdump crashkernel's working memory over to dynamic allocation. So the difficulty of a-priori estimation of the second kernel's needs is removed and the first kernel obtains extra memory - "generalize panic_print's dump function to be used by other kernel parts" (Feng Tang) implements some consolidation and rationalization of the various ways in which a failing kernel splats information at the operator * tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (80 commits) tools/getdelays: add backward compatibility for taskstats version kho: add test for kexec handover delaytop: enhance error logging and add PSI feature description samples: Kconfig: fix spelling mistake "instancess" -> "instances" fat: fix too many log in fat_chain_add() scripts/spelling.txt: add notifer||notifier to spelling.txt xen/xenbus: fix typo "notifer" net: mvneta: fix typo "notifer" drm/xe: fix typo "notifer" cxl: mce: fix typo "notifer" KVM: x86: fix typo "notifer" MAINTAINERS: add maintainers for delaytop ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below() ucount: fix atomic_long_inc_below() argument type kexec: enable CMA based contiguous allocation stackdepot: make max number of pools boot-time configurable lib/xxhash: remove unused functions init/Kconfig: restore CONFIG_BROKEN help text lib/raid6: update recov_rvv.c zero page usage docs: update docs after introducing delaytop ...
2025-08-02stackdepot: make max number of pools boot-time configurableMatt Fleming
We're hitting the WARN in depot_init_pool() about reaching the stack depot limit because we have long stacks that don't dedup very well. Introduce a new start-up parameter to allow users to set the number of maximum stack depot pools. Link: https://lkml.kernel.org/r/20250718153928.94229-1-matt@readmodwrite.com Signed-off-by: Matt Fleming <mfleming@cloudflare.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-31Merge tag 'cgroup-for-6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: - Allow css_rstat_updated() in NMI context to enable memory accounting for allocations in NMI context. - /proc/cgroups doesn't contain useful information for cgroup2 and was updated to only show v1 controllers. This unfortunately broke something in the wild. Add an option to bring back the old behavior to ease transition. - selftest updates and other cleanups. * tag 'cgroup-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: Add compatibility option for content of /proc/cgroups selftests/cgroup: fix cpu.max tests cgroup: llist: avoid memory tears for llist_node selftests: cgroup: Fix missing newline in test_zswap_writeback_one selftests: cgroup: Allow longer timeout for kmem_dead_cgroups cleanup memcg: cgroup: call css_rstat_updated irrespective of in_nmi() cgroup: remove per-cpu per-subsystem locks cgroup: make css_rstat_updated nmi safe cgroup: support to enable nmi-safe css_rstat_updated selftests: cgroup: Fix compilation on pre-cgroupns kernels selftests: cgroup: Optionally set up v1 environment selftests: cgroup: Add support for named v1 hierarchies in test_core selftests: cgroup_util: Add helpers for testing named v1 hierarchies Documentation: cgroup: add section explaining controller availability cgroup: Drop sock_cgroup_classid() dummy implementation
2025-07-31Merge tag 'integrity-v6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull integrity update from Mimi Zohar: "A single commit to permit disabling IMA from the boot command line for just the kdump kernel. The exception itself sort of makes sense. My concern is that exceptions do not remain as exceptions, but somehow morph to become the norm" * tag 'integrity-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: ima: add a knob ima= to allow disabling IMA in kdump kernel
2025-07-30Merge tag 'slab-for-6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab Pull slab updates from Vlastimil Babka: - Convert struct slab to its own flags instead of referencing page flags, which is another preparation step before separating it from struct page completely. Along with that, a bunch of documentation fixes and cleanups (Matthew Wilcox) - Convert large kmalloc to use frozen pages in order to be consistent with non-large kmalloc slabs (Vlastimil Babka) - MAINTAINERS updates (Matthew Wilcox, Lorenzo Stoakes) - Restore NUMA policy support for large kmalloc, broken by mistake in v6.1 (Vlastimil Babka) * tag 'slab-for-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: MAINTAINERS: add missing files to slab section slab: Update MAINTAINERS entry memcg_slabinfo: Fix use of PG_slab kfence: Remove mention of PG_slab vmcoreinfo: Remove documentation of PG_slab and PG_hugetlb doc: Add slab internal kernel-doc slub: Fix a documentation build error for krealloc() slab: Add SL_pfmemalloc flag slab: Add SL_partial flag slab: Rename slab->__page_flags to slab->flags doc: Move SLUB documentation to the admin guide mm, slab: use frozen pages for large kmalloc mm, slab: restore NUMA policy support for large kmalloc
2025-07-30Merge tag 'rcu.release.v6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux Pull RCU updates from Neeraj Upadhyay: "Expedited grace period updates: - Protect against early RCU exp quiescent state reporting during exp grace period initialization - Remove superfluous barrier in task unblock path - Remove the CPU online quiescent state report optimization, which is error prone for certain scenarios - Add warning for unexpected pending requested expedited quiescent state on dying CPU Core: - Robustify rcu_is_cpu_rrupt_from_idle() by using more accurate indicators of the actual context tracking state of a CPU - Handle ->defer_qs_iw_pending field data race - Enable rcu_normal_wake_from_gp by default on systems with <= 16 CPUs - Fix lockup in rcu_read_unlock() due to recursive irq_exit() calls - Refactor expedited handling condition in rcu_read_unlock_special() - Documentation updates for hotplug and GP init scan ordering, separation of rcu_state and rnp's gp_seq states, quiescent state reporting for offline CPUs torture-scripts: - Cleanup and improve scripts : remove superfluous warnings for disabled tests; better handling of kvm.sh --kconfig arg; suppress some confusing diagnostics; tolerate bad kvm.sh args; add new diagnostic for build output; fail allmodconfig testing on warnings - Include RCU_TORTURE_TEST_CHK_RDR_STATE config for KCSAN kernels - Disable default RCU-tasks and clocksource-wdog testing on arm64 - Add EXPERT Kconfig option for arm64 KCSAN runs - Remove SRCU-lite testing rcutorture: - Start torture writer threads creation after reader threads to handle race in SRCU-P scenario - Add SRCU down_read()/up_read() test - Add diagnostics for delayed SRCU up_read(), unmatched up_read(), print number of up/down readers and the number of such readers which migrated to other CPU - Ignore certain unsupported configurations for trivial RCU test - Fix splats in RT kernels due to inaccurate checks for BH-disabled context - Enable checks and logs to capture intentionally exercised unexpected scenarios (too short readers) for BUSTED test - Remove SRCU-lite testing srcu: - Expedite SRCU-fast grace periods - Remove SRCU-lite implementation - Add guards for SRCU-fast readers rcu nocb: - Dump NOCB group leader state on stall detection - Robustify nocb_cb_kthread pointer accesses - Fix delayed execution of hurry callbacks when LAZY_RCU is enabled refscale: - Fix multiplication overflow in "loops" and "nreaders" calculations" * tag 'rcu.release.v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (49 commits) rcu: Document concurrent quiescent state reporting for offline CPUs rcu: Document separation of rcu_state and rnp's gp_seq rcu: Document GP init vs hotplug-scan ordering requirements srcu: Add guards for SRCU-fast readers rcu: Fix delayed execution of hurry callbacks rcu: Refactor expedited handling check in rcu_read_unlock_special() checkpatch: Remove SRCU-lite deprecation srcu: Remove SRCU-lite implementation srcu: Expedite SRCU-fast grace periods rcutorture: Remove support for SRCU-lite rcutorture: Remove SRCU-lite scenarios torture: Remove support for SRCU-lite torture: Make torture.sh --allmodconfig testing fail on warnings torture: Add "ERROR" diagnostic for testing kernel-build output torture: Make torture.sh tolerate runs having bad kvm.sh arguments torture: Add textid.txt file to --do-allmodconfig and --do-rcu-rust runs torture: Extract testid.txt generation to separate script torture: Suppress "find" diagnostics from torture.sh --do-none run torture: Provide EXPERT Kconfig option for arm64 KCSAN torture.sh runs rcu: Fix rcu_read_unlock() deadloop due to IRQ work ...
2025-07-29Merge tag 'sched-core-2025-07-28' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Core scheduler changes: - Better tracking of maximum lag of tasks in presence of different slices duration, for better handling of lag in the fair scheduler (Vincent Guittot) - Clean up and standardize #if/#else/#endif markers throughout the entire scheduler code base (Ingo Molnar) - Make SMP unconditional: build the SMP scheduler's data structures and logic on UP kernel too, even though they are not used, to simplify the scheduler and remove around 200 #ifdef/[#else]/#endif blocks from the scheduler (Ingo Molnar) - Reorganize cgroup bandwidth control interface handling for better interfacing with sched_ext (Tejun Heo) Balancing: - Bump sd->max_newidle_lb_cost when newidle balance fails (Chris Mason) - Remove sched_domain_topology_level::flags to simplify the code (Prateek Nayak) - Simplify and clean up build_sched_topology() (Li Chen) - Optimize build_sched_topology() on large machines (Li Chen) Real-time scheduling: - Add initial version of proxy execution: a mechanism for mutex-owning tasks to inherit the scheduling context of higher priority waiters. Currently limited to a single runqueue and conditional on CONFIG_EXPERT, and other limitations (John Stultz, Peter Zijlstra, Valentin Schneider) - Deadline scheduler (Juri Lelli): - Fix dl_servers initialization order (Juri Lelli) - Fix DL scheduler's root domain reinitialization logic (Juri Lelli) - Fix accounting bugs after global limits change (Juri Lelli) - Fix scalability regression by implementing less agressive dl_server handling (Peter Zijlstra) PSI: - Improve scalability by optimizing psi_group_change() cpu_clock() usage (Peter Zijlstra) Rust changes: - Make Task, CondVar and PollCondVar methods inline to avoid unnecessary function calls (Kunwu Chan, Panagiotis Foliadis) - Add might_sleep() support for Rust code: Rust's "#[track_caller]" mechanism is used so that Rust's might_sleep() doesn't need to be defined as a macro (Fujita Tomonori) - Introduce file_from_location() (Boqun Feng) Debugging & instrumentation: - Make clangd usable with scheduler source code files again (Peter Zijlstra) - tools: Add root_domains_dump.py which dumps root domains info (Juri Lelli) - tools: Add dl_bw_dump.py for printing bandwidth accounting info (Juri Lelli) Misc cleanups & fixes: - Remove play_idle() (Feng Lee) - Fix check_preemption_disabled() (Sebastian Andrzej Siewior) - Do not call __put_task_struct() on RT if pi_blocked_on is set (Luis Claudio R. Goncalves) - Correct the comment in place_entity() (wang wei)" * tag 'sched-core-2025-07-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (84 commits) sched/idle: Remove play_idle() sched: Do not call __put_task_struct() on rt if pi_blocked_on is set sched: Start blocked_on chain processing in find_proxy_task() sched: Fix proxy/current (push,pull)ability sched: Add an initial sketch of the find_proxy_task() function sched: Fix runtime accounting w/ split exec & sched contexts sched: Move update_curr_task logic into update_curr_se locking/mutex: Add p->blocked_on wrappers for correctness checks locking/mutex: Rework task_struct::blocked_on sched: Add CONFIG_SCHED_PROXY_EXEC & boot argument to enable/disable sched/topology: Remove sched_domain_topology_level::flags x86/smpboot: avoid SMT domain attach/destroy if SMT is not enabled x86/smpboot: moves x86_topology to static initialize and truncate x86/smpboot: remove redundant CONFIG_SCHED_SMT smpboot: introduce SDTL_INIT() helper to tidy sched topology setup tools/sched: Add dl_bw_dump.py for printing bandwidth accounting info tools/sched: Add root_domains_dump.py which dumps root domains info sched/deadline: Fix accounting after global limits change sched/deadline: Reset extra_bw to max_bw when clearing root domains sched/deadline: Initialize dl_servers after SMP ...
2025-07-29Merge tag 'x86_bugs_for_v6.17_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 CPU mitigation updates from Borislav Petkov: - Untangle the Retbleed from the ITS mitigation on Intel. Allow for ITS to enable stuffing independently from Retbleed, do some cleanups to simplify and streamline the code - Simplify SRSO and make mitigation types selection more versatile depending on the Retbleed mitigation selection. Simplify code some - Add the second part of the attack vector controls which provide a lot friendlier user interface to the speculation mitigations than selecting each one by one as it is now. Instead, the selection of whole attack vectors which are relevant to the system in use can be done and protection against only those vectors is enabled, thus giving back some performance to the users * tag 'x86_bugs_for_v6.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits) x86/bugs: Print enabled attack vectors x86/bugs: Add attack vector controls for TSA x86/pti: Add attack vector controls for PTI x86/bugs: Add attack vector controls for ITS x86/bugs: Add attack vector controls for SRSO x86/bugs: Add attack vector controls for L1TF x86/bugs: Add attack vector controls for spectre_v2 x86/bugs: Add attack vector controls for BHI x86/bugs: Add attack vector controls for spectre_v2_user x86/bugs: Add attack vector controls for retbleed x86/bugs: Add attack vector controls for spectre_v1 x86/bugs: Add attack vector controls for GDS x86/bugs: Add attack vector controls for SRBDS x86/bugs: Add attack vector controls for RFDS x86/bugs: Add attack vector controls for MMIO x86/bugs: Add attack vector controls for TAA x86/bugs: Add attack vector controls for MDS x86/bugs: Define attack vectors relevant for each bug x86/Kconfig: Add arch attack vector support cpu: Define attack vectors ...
2025-07-29Merge tag 'irq-drivers-2025-07-27' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull interrupt chip driver updates from Thomas Gleixner: - Add support of forced affinity setting to yet offline CPUs for the MIPS-GIC to ensure that the affinity of per CPU interrupts can be set during the early bringup phase of a secondary CPU in the hotplug code before the CPU is set online and interrupts are enabled - Add support for the MIPS (RISC-V !?!?) P8700 SoC in the ACLINT_SSWI interrupt chip - Make the interrupt routing to RISV-V harts specification compliant so it supports arbitrary hart indices - Add a command line parameter and related handling to disable the generic RISCV IMSIC mechanism on platforms which use a trap-emulated IMSIC. Unfortunatly this is required because there is no mechanism available to discover this programatically. - Enable wakeup sources on the Renesas RZV2H driver - Convert interrupt chip drivers, which use a open coded variant of msi_create_parent_irq_domain() to use the new functionality - Convert interrupt chip drivers, which use the old style two level implementation of MSI support over to the MSI parent mechanism to prepare for removing at least one of the three PCI/MSI backend variants. - The usual cleanups and improvements all over the place * tag 'irq-drivers-2025-07-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits) irqchip/renesas-irqc: Convert to DEFINE_SIMPLE_DEV_PM_OPS() irqchip/renesas-intc-irqpin: Convert to DEFINE_SIMPLE_DEV_PM_OPS() irqchip/riscv-imsic: Add kernel parameter to disable IPIs irqchip/gic-v3: Fix GICD_CTLR register naming irqchip/ls-scfg-msi: Fix NULL dereference in error handling irqchip/ls-scfg-msi: Switch to use msi_create_parent_irq_domain() irqchip/armada-370-xp: Switch to msi_create_parent_irq_domain() irqchip/alpine-msi: Switch to msi_create_parent_irq_domain() irqchip/alpine-msi: Convert to __free irqchip/alpine-msi: Convert to lock guards irqchip/alpine-msi: Clean up whitespace style irqchip/sg2042-msi: Switch to msi_create_parent_irq_domain() irqchip/loongson-pch-msi.c: Switch to msi_create_parent_irq_domain() irqchip/imx-mu-msi: Convert to msi_create_parent_irq_domain() helper irqchip/riscv-imsic: Convert to msi_create_parent_irq_domain() helper irqchip/bcm2712-mip: Switch to msi_create_parent_irq_domain() irqdomain: Add device pointer to irq_domain_info and msi_domain_info irqchip/renesas-rzv2h: Remove unneeded includes irqchip/renesas-rzv2h: Enable SKIP_SET_WAKE and MASK_ON_SUSPEND irqchip/aslint-sswi: Resolve hart index ...
2025-07-28Merge tag 'pm-6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "As is tradition, cpufreq is the part with the largest number of updates that include core fixes and cleanups as well as updates of several assorted drivers, but there are also quite a few updates related to system sleep, mostly focused on asynchronous suspend and resume of devices and on making the integration of system suspend and resume with runtime PM easier. Runtime PM is also updated to allow some code duplication in drivers to be eliminated going forward and to work more consistently overall in some cases. Apart from that, there are some driver core updates related to PM domains that should help to address ordering issues with devm_ cleanup routines relying on PM domains, some assorted devfreq updates including core fixes and cleanups, tooling updates, and documentation and MAINTAINERS updates. Specifics: - Fix two initialization ordering issues in the cpufreq core and a governor initialization error path in it, and clean it up (Lifeng Zheng) - Add Granite Rapids support in no-HWP mode to the intel_pstate cpufreq driver (Li RongQing) - Make intel_pstate always use HWP_DESIRED_PERF when operating in the passive mode (Rafael Wysocki) - Allow building the tegra124 cpufreq driver as a module (Aaron Kling) - Do minor cleanups for Rust cpufreq and cpumask APIs and fix MAINTAINERS entry for cpu.rs (Abhinav Ananthu, Ritvik Gupta, Lukas Bulwahn) - Clean up assorted cpufreq drivers (Arnd Bergmann, Dan Carpenter, Krzysztof Kozlowski, Sven Peter, Svyatoslav Ryhel, Lifeng Zheng) - Add the NEED_UPDATE_LIMITS flag to the CPPC cpufreq driver (Prashant Malani) - Fix minimum performance state label error in the amd-pstate driver documentation (Shouye Liu) - Add the CPUFREQ_GOV_STRICT_TARGET flag to the userspace cpufreq governor and explain HW coordination influence on it in the documentation (Shashank Balaji) - Fix opencoded for_each_cpu() in idle_state_valid() in the DT cpuidle driver (Yury Norov) - Remove info about non-existing QoS interfaces from the PM QoS documentation (Ulf Hansson) - Use c_* types via kernel prelude in Rust for OPP (Abhinav Ananthu) - Add HiSilicon uncore frequency scaling driver to devfreq (Jie Zhan) - Allow devfreq drivers to add custom sysfs ABIs (Jie Zhan) - Simplify the sun8i-a33-mbus devfreq driver by using more devm functions (Uwe Kleine-König) - Fix an index typo in trans_stat() in devfreq (Chanwoo Choi) - Check devfreq governor before using governor->name (Lifeng Zheng) - Remove a redundant devfreq_get_freq_range() call from devfreq_add_device() (Lifeng Zheng) - Limit max_freq with scaling_min_freq in devfreq (Lifeng Zheng) - Replace sscanf() with kstrtoul() in set_freq_store() (Lifeng Zheng) - Extend the asynchronous suspend and resume of devices to handle suppliers like parents and consumers like children (Rafael Wysocki) - Make pm_runtime_force_resume() work for drivers that set the DPM_FLAG_SMART_SUSPEND flag and allow PCI drivers and drivers that collaborate with the general ACPI PM domain to set it (Rafael Wysocki) - Add kernel parameter to disable asynchronous suspend/resume of devices (Tudor Ambarus) - Drop redundant might_sleep() calls from some functions in the device suspend/resume core code (Zhongqiu Han) - Fix the handling of monitors connected right before waking up the system from sleep (tuhaowen) - Clean up MAINTAINERS entries for suspend and hibernation (Rafael Wysocki) - Fix error code path in the KEXEC_JUMP flow and drop a redundant pm_restore_gfp_mask() call from it (Rafael Wysocki) - Rearrange suspend/resume error handling in the core device suspend and resume code (Rafael Wysocki) - Fix up white space that does not follow coding style in the hibernation core code (Darshan Rathod) - Document return values of suspend-related API functions in the runtime PM framework (Sakari Ailus) - Mark last busy stamp in multiple autosuspend-related functions in the runtime PM framework and update its documentation (Sakari Ailus) - Take active children into account in pm_runtime_get_if_in_use() for consistency (Rafael Wysocki) - Fix NULL pointer dereference in get_pd_power_uw() in the dtpm_cpu power capping driver (Sivan Zohar-Kotzer) - Add support for the Bartlett Lake platform to the Intel RAPL power capping driver (Qiao Wei) - Add PL4 support for Panther Lake to the intel_rapl_msr power capping driver (Zhang Rui) - Update contact information in the PM ABI docs and maintainer information in the power domains DT binding (Rafael Wysocki) - Update PM header inclusions to follow the IWYU (Include What You Use) principle (Andy Shevchenko) - Add flags to specify power on attach/detach for PM domains, make the driver core detach PM domains in device_unbind_cleanup(), and drop the dev_pm_domain_detach() call from the platform bus type (Claudiu Beznea) - Improve Python binding's Makefile for cpupower (John B. Wyatt IV) - Fix printing of CORE, CPU fields in cpupower-monitor (Gautham Shenoy)" * tag 'pm-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (75 commits) cpufreq: CPPC: Mark driver with NEED_UPDATE_LIMITS flag PM: docs: Use my kernel.org address in ABI docs and DT bindings PM: hibernate: Fix up white space that does not follow coding style PM: sleep: Rearrange suspend/resume error handling in the core Documentation: amd-pstate:fix minimum performance state label error PM: runtime: Take active children into account in pm_runtime_get_if_in_use() kexec_core: Drop redundant pm_restore_gfp_mask() call kexec_core: Fix error code path in the KEXEC_JUMP flow PM: sleep: Clean up MAINTAINERS entries for suspend and hibernation drivers: cpufreq: add Tegra114 support rust: cpumask: Replace `MaybeUninit` and `mem::zeroed` with `Opaque` APIs cpufreq: Exit governor when failed to start old governor cpufreq: Move the check of cpufreq_driver->get into cpufreq_verify_current_freq() cpufreq: Init policy->rwsem before it may be possibly used cpufreq: Initialize cpufreq-based frequency-invariance later cpufreq: Remove duplicate check in __cpufreq_offline() cpufreq: Contain scaling_cur_freq.attr in cpufreq_attrs cpufreq: intel_pstate: Add Granite Rapids support in no-HWP mode cpufreq: intel_pstate: Always use HWP_DESIRED_PERF in passive mode PM / devfreq: Add HiSilicon uncore frequency scaling driver ...
2025-07-23tpm_crb_ffa: handle tpm busy return codePrachotan Bathi
Platforms supporting direct message request v2 [1] can support secure partitions that support multiple services. For CRB over FF-A interface, if the firmware TPM or TPM service [1] shares its Secure Partition (SP) with another service, message requests may fail with a -EBUSY error. To handle this, replace the single check and call with a retry loop that attempts the TPM message send operation until it succeeds or a configurable timeout is reached. Implement a _try_send_receive function to do a single send/receive and modify the existing send_receive to add this retry loop. The retry mechanism introduces a module parameter (`busy_timeout_ms`, default: 2000ms) to control how long to keep retrying on -EBUSY responses. Between retries, the code waits briefly (50-100 microseconds) to avoid busy-waiting and handling TPM BUSY conditions more gracefully. The parameter can be modified at run-time as such: echo 3000 | tee /sys/module/tpm_crb_ffa/parameters/busy_timeout_ms This changes the timeout from the default 2000ms to 3000ms. [1] TPM Service Command Response Buffer Interface Over FF-A https://developer.arm.com/documentation/den0138/latest/ Signed-off-by: Prachotan Bathi <prachotan.bathi@arm.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2025-07-19panic: add note that panic_print sysctl interface is deprecatedFeng Tang
Add a dedicated core parameter 'panic_console_replay' for controlling console replay, and add note that 'panic_print' sysctl interface will be obsoleted by 'panic_sys_info' and 'panic_console_replay'. When it happens, the SYS_INFO_PANIC_CONSOLE_REPLAY can be removed as well. Link: https://lkml.kernel.org/r/20250703021004.42328-6-feng.tang@linux.alibaba.com Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com> Suggested-by: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19panic: add 'panic_sys_info=' setup option for kernel cmdlineFeng Tang
'panic_sys_info=' sysctl interface is already added for runtime setting. Add counterpart kernel cmdline option for boottime setting. Link: https://lkml.kernel.org/r/20250703021004.42328-5-feng.tang@linux.alibaba.com Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com> Suggested-by: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19panic: clean up code for console replayFeng Tang
Patch series "generalize panic_print's dump function to be used by other kernel parts", v3. When working on kernel stability issues, panic, task-hung and software/hardware lockup are frequently met. And to debug them, user may need lots of system information at that time, like task call stacks, lock info, memory info etc. panic case already has panic_print_sys_info() for this purpose, and has a 'panic_print' bitmask to control what kinds of information is needed, which is also helpful to debug other task-hung and lockup cases. So this patchset extracts the function out to a new file 'lib/sys_info.c', and makes it available for other cases which also need to dump system info for debugging. Also as suggested by Petr Mladek, add 'panic_sys_info=' interface to take human readable string like "tasks,mem,locks,timers,ftrace,....", and eventually obsolete the current 'panic_print' bitmap interface. In RFC and V1 version, hung_task and SW/HW watchdog modules are enabled with the new sys_info dump interface. In v2, they are kept out for better review of current change, and will be posted later. Locally these have been used in our bug chasing for stability issues and was proven helpful. Many thanks to Petr Mladek for great suggestions on both the code and architectures! This patch (of 5): Currently the panic_print_sys_info() was called twice with different parameters to handle console replay case, which is kind of confusing. Add panic_console_replay() explicitly and rename 'PANIC_PRINT_ALL_PRINTK_MSG' to 'PANIC_CONSOLE_REPLAY', to make the code straightforward. The related kernel document is also updated. Link: https://lkml.kernel.org/r/20250703021004.42328-1-feng.tang@linux.alibaba.com Link: https://lkml.kernel.org/r/20250703021004.42328-2-feng.tang@linux.alibaba.com Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com> Suggested-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19kdump, documentation: describe craskernel CMA reservationJiri Bohac
Describe the new crashkernel ",cma" suffix in Documentation/ Link: https://lkml.kernel.org/r/aEqpQwUy6gqSiUkV@dwarf.suse.cz Signed-off-by: Jiri Bohac <jbohac@suse.cz> Cc: Baoquan He <bhe@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Donald Dutile <ddutile@redhat.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Philipp Rudo <prudo@redhat.com> Cc: Pingfan Liu <piliu@redhat.com> Cc: Tao Liu <ltao@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19cgroup: Add compatibility option for content of /proc/cgroupsMichal Koutný
/proc/cgroups lists only v1 controllers by default, however, this is only enforced since the commit af000ce85293b ("cgroup: Do not report unavailable v1 controllers in /proc/cgroups") and there is software in the wild that uses content of /proc/cgroups to decide on availability of v2 (sic) controllers. Add a boottime param that can bring back the previous behavior for setups where the check in the software cannot be changed and it causes e.g. unintended OOMs. Also, this patch takes out cgrp_v1_visible from cgroup1_subsys_absent() guard since it's only important to check which hierarchy (v1 vs v2) the subsys is attached to. This has no effect on the printed message but the code is cleaner since cgrp_v1_visible is really about mounted hierarchies, not the content of /proc/cgroups. Link: https://lore.kernel.org/r/b26b60b7d0d2a5ecfd2f3c45f95f32922ed24686.camel@decadent.org.uk Fixes: af000ce85293b ("cgroup: Do not report unavailable v1 controllers in /proc/cgroups") Fixes: a0ab1453226d8 ("cgroup: Print message when /proc/cgroups is read on v2-only system") Signed-off-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-07-18irqchip/riscv-imsic: Add kernel parameter to disable IPIsAnup Patel
When injecting IPIs to a set of harts, the IMSIC IPI support will do a separate MMIO write to the SETIPNUM_LE register of each target hart. This means on a platform where IMSIC is trap-n-emulated, there will be N MMIO traps when injecting IPI to N target harts hence IMSIC IPIs will be slow on such platforms compared to the SBI IPI extension. Unfortunately, there is no DT, ACPI, or any other way of discovering whether the underlying IMSIC is trap-n-emulated. Using MMIO write to the SETIPNUM_LE register for injecting IPI is purely a software choice in the IMSIC driver hence add a kernel parameter to allow users to disable IMSIC IPIs on platforms with trap-n-emulated IMSIC. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250716123745.557585-1-apatel@ventanamicro.com
2025-07-17Merge back earlier material related to system sleepRafael J. Wysocki
2025-07-16Documentation/kernel-parameters: Update rcu_normal_wake_from_gp docUladzislau Rezki (Sony)
Update the documentation about rcu_normal_wake_from_gp parameter. Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.upadhyay@kernel.org>
2025-07-14sched: Add CONFIG_SCHED_PROXY_EXEC & boot argument to enable/disableJohn Stultz
Add a CONFIG_SCHED_PROXY_EXEC option, along with a boot argument sched_proxy_exec= that can be used to disable the feature at boot time if CONFIG_SCHED_PROXY_EXEC was enabled. Also uses this option to allow the rq->donor to be different from rq->curr. Signed-off-by: John Stultz <jstultz@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: K Prateek Nayak <kprateek.nayak@amd.com> Link: https://lkml.kernel.org/r/20250712033407.2383110-2-jstultz@google.com
2025-07-11Documentation/x86: Document new attack vector controlsDavid Kaplan
Document the 5 new attack vector command line options, how they interact with existing vulnerability controls, and recommendations on when they can be disabled. Note that while mitigating against untrusted userspace requires both user-to-kernel and user-to-user protection, these are kept separate. The kernel can control what code executes inside of it and that may affect the risk associated with vulnerabilities especially if new kernel mitigations are implemented. The same isn't typically true of userspace. In other words, the risk associated with user-to-user or guest-to-guest attacks is unlikely to change over time. While the risk associated with user-to-kernel or guest-to-host attacks may change. Therefore, these controls are separated. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250709155731.3279419-1-david.kaplan@amd.com
2025-07-10PM: sleep: add kernel parameter to disable asynchronous suspend/resumeTudor Ambarus
On some platforms, device dependencies are not properly represented by device links, which can cause issues when asynchronous power management is enabled. While it is possible to disable this via sysfs, doing so at runtime can race with the first system suspend event. This patch introduces a kernel command-line parameter, "pm_async", which can be set to "off" to globally disable asynchronous suspend and resume operations from early boot. It effectively provides a way to set the initial value of the existing pm_async sysfs knob at boot time. This offers a robust method to fall back to synchronous (sequential) operation, which can stabilize platforms with problematic dependencies and also serve as a useful debugging tool. The default behavior remains unchanged (asynchronous enabled). To disable it, boot the kernel with the "pm_async=off" parameter. Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Link: https://patch.msgid.link/20250709-pm-async-off-v3-1-cb69a6fc8d04@linaro.org Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-06-18doc: Move SLUB documentation to the admin guideMatthew Wilcox (Oracle)
This section is supposed to be for internal documentation, while the document is advice for sysadmins. Move it to the appropriate place. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Harry Yoo <harry.yoo@oracle.com> Link: https://patch.msgid.link/20250611155916.2579160-2-willy@infradead.org Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2025-06-17x86/bugs: Add a Transient Scheduler Attacks mitigationBorislav Petkov (AMD)
Add the required features detection glue to bugs.c et all in order to support the TSA mitigation. Co-developed-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
2025-06-16ima: add a knob ima= to allow disabling IMA in kdump kernelBaoquan He
Kdump kernel doesn't need IMA functionality, and enabling IMA will cost extra memory. It would be very helpful to allow IMA to be disabled for kdump kernel. Hence add a knob ima=on|off here to allow turning IMA off in kdump kernel if needed. Note that this IMA disabling is limited to kdump kernel, please don't abuse it in other kernel and thus serious consequences are caused. Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2025-06-09slab: Decouple slab_debug and no_hash_pointersKees Cook
Some system owners use slab_debug=FPZ (or similar) as a hardening option, but do not want to be forced into having kernel addresses exposed due to the implicit "no_hash_pointers" boot param setting.[1] Introduce the "hash_pointers" boot param, which defaults to "auto" (the current behavior), but also includes "always" (forcing on hashing even when "slab_debug=..." is defined), and "never". The existing "no_hash_pointers" boot param becomes an alias for "hash_pointers=never". This makes it possible to boot with "slab_debug=FPZ hash_pointers=always". Link: https://github.com/KSPP/linux/issues/368 [1] Fixes: 792702911f58 ("slub: force on no_hash_pointers when slub_debug is enabled") Co-developed-by: Sergio Perez Gonzalez <sperezglz@gmail.com> Signed-off-by: Sergio Perez Gonzalez <sperezglz@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Kees Cook <kees@kernel.org> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Rafael Aquini <raquini@redhat.com> Tested-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://patch.msgid.link/20250415170232.it.467-kees@kernel.org [kees@kernel.org: Add note about hash_pointers into slab_debug kernel parameter documentation.] Signed-off-by: Petr Mladek <pmladek@suse.com>
2025-06-05Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "We've got a couple of build fixes when using LLD, a missing TLB invalidation and a workaround for broken firmware on SoCs with CPUs that implement MPAM: - Disable problematic linker assertions for broken versions of LLD - Work around sporadic link failure with LLD and various randconfig builds - Fix missing invalidation in the TLB batching code when reclaim races with mprotect() and friends - Add a command-line override for MPAM to allow booting on systems with broken firmware" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: Add override for MPAM arm64/mm: Close theoretical race where stale TLB entry remains valid arm64: Work around convergence issue with LLD linker arm64: Disable LLD linker ASSERT()s for the time being