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2026-07-22smp: Avoid invalid per-CPU CSD lookup with CSD lock debugChuyi Zhou1-1/+2
Commit b0473dcd4b1d ("smp: Improve smp_call_function_single() CSD-lock diagnostics") made smp_call_function_single() use the destination CPU's csd_data when CSD lock debugging is enabled. That lets the debug code associate a stuck CSD lock with the target CPU, but it also means the CPU argument is used in per_cpu_ptr() before generic_exec_single() has a chance to validate it. This becomes unsafe when smp_call_function_any() cannot find an online CPU in the supplied mask. In that case the selected CPU can be nr_cpu_ids, and the !wait path calls get_single_csd_data(cpu) before generic_exec_single() returns -ENXIO. With csdlock_debug_enabled set, that indexes the per-CPU offset array with an invalid CPU number. Use the destination CPU's csd_data only when the CPU number is within nr_cpu_ids. For invalid CPU numbers, fall back to the local CPU's csd_data and let generic_exec_single() perform the existing validation and return -ENXIO. Fixes: b0473dcd4b1d ("smp: Improve smp_call_function_single() CSD-lock diagnostics") Signed-off-by: Chuyi Zhou <zhouchuyi@bytedance.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Muchun Song <muchun.song@linux.dev> Link: https://patch.msgid.link/20260716004539.13983-1-paulmck@kernel.org
2026-07-22Merge tag 'liveupdate-fixes-2026-07-22' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linuxLinus Torvalds1-1/+1
Pull liveupdate fix from Mike Rapoport: - Fix validation of LIVEUPDATE_SESSION_GET_NAME ioctl argument caused by a wrong resolution of a merge conflict during the last merge window * tag 'liveupdate-fixes-2026-07-22' of git://git.kernel.org/pub/scm/linux/kernel/git/liveupdate/linux: liveupdate: fix GET_NAME ioctl argument validation
2026-07-22sched_ext: Fix stale errno in scx_sub_enable_workfn()Cui Jian1-0/+2
The nesting depth check and the cgroup online check in scx_sub_enable_workfn() reach err_disable without setting ret, so the fallback error added by commit db4e9defd2e8 ("sched_ext: Record an error on errno-only sub-enable failure") reports "scx_sub_enable() failed (0)". This is currently harmless because both paths record their own scx_error() first and the first error wins, but it leaves the fallback broken for these paths. Set -EINVAL and -ENODEV there so the fallback always reports a real errno. v2: The validate_ops() path from v1 is already fixed in for-7.3 (sub.c already has ret = scx_validate_ops()), so only the two remaining paths are addressed. Signed-off-by: Cui Jian <cjian720@163.com> Reviewed-by: Andrea Righi <arighi@nvidia.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-07-22sched_ext: Mark waker CPU busy when selected in WAKE_SYNC caseKuba Piecuch1-1/+3
SCX's built-in idle CPU tracking is imperfect and can be out-of-sync with the actual idle state of CPUs, especially immediately after enabling SCX due to scx_idle_enable() marking all online CPUs idle. scx_select_cpu_dfl() skips marking the selected CPU as busy if the selected CPU is the waker CPU in the SCX_WAKE_SYNC case. If the waker CPU was marked idle by SCX, it will still be marked idle after CPU selection and potentially even after switching to the wakee. In the allowed_cpus selftest, this can manifest as the test failing with the following message in dmesg: allowed_cpus.bpf.c:21: CPU 0 should be marked as busy This patch explicitly marks the waker CPU as busy. With this patch, the test failure no longer reproduces. There are still some pretty unlikely races that could make the test fail (e.g. pick_task_idle() marking the selected CPU idle between selection and validation), but these can't be fixed easily. Signed-off-by: Kuba Piecuch <jpiecuch@google.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-07-22Merge tag 'ath-next-20260722' of git://git.kernel.org/pub/scm/linux/kernel/git/ath/athJohannes Berg1-0/+1
Jeff Johnson says: ================== ath.git patches for v7.3 (PR #1) There has been quite a bit of activity across the ath drivers. Significant changes in ath12k include: Align with new Qualcomm generic Peripheral Authentication Service (PAS). Ongoing infrastructure changes to support the QCC2072 platform. Ongoing infrastructure changes to support the IPQ5332 platform. Enhance datapath statistics. Tuning of datapath parameters. In addition, an assortment of cleanups and minor bug fixes across ath6kl, ath10k, ath11k, ath12k, and carl9170. ================== Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2026-07-22bpf, x86: Make sure allocation in arch_bpf_trampoline_size() is writableMike Rapoport (Microsoft)1-0/+5
arch_bpf_trampoline_size() allocates a buffer to get actual size required for a trampoline. This buffer must be in the module address space because __arch_prepare_bpf_trampoline() calculates rel32 offsets relatively to that buffer. In preparation for enabling ROX mode for EXECMEM_BPF make sure that the allocated memory is writable. Add bpf_jit_alloc_exec_rw() wrapper for execmem_alloc_rw() and use it for buffer allocation in arch_bpf_trampoline_size(). Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20260716-execmem-x86-rox-bpf-v0-v3-4-4e76158c01c5@kernel.org Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-22bpf: alloc_prog_pack(): Skip ROX management for already ROX memoryMike Rapoport (Microsoft)1-7/+14
execmem_alloc() can return ROX memory that is already filled with architecture defined trapping instructions. In preparation for enabling this mode for BPF on x86, make sure that there is no redundant management of the ROX memory. There is no need to fill allocated memory with trapping instructions, to request permissions reset on free and to set ROX permissions as this all is handled by execmem_alloc(). Add bpf_jit_mem_is_rox() wrapper for execmem_is_rox(), use it to check if execmem_alloc() returns ROX memory and skip the redundant steps in that case. Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20260716-execmem-x86-rox-bpf-v0-v3-3-4e76158c01c5@kernel.org Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-22bpf: Drop __weak from bpf_jit_alloc_exec() and bpf_jit_free_exec()Mike Rapoport (Microsoft)1-2/+2
bpf_jit_alloc_exec() and bpf_jit_free_exec() are wrappers for the corresponding execmem APIs. Architectures define the properties of the memory range needed by BPF in their initialization of execmem and don't need to override neither of them. Drop the __weak qualifier from bpf_jit_alloc_exec() and bpf_jit_free_exec(). Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20260716-execmem-x86-rox-bpf-v0-v3-2-4e76158c01c5@kernel.org Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-22bpf: dispatcher: Allocate bpf_dispatcher->rw_image with vzalloc()Mike Rapoport (Microsoft)1-1/+4
bpf_dispatcher->rw_image is a temporary writable buffer that arch_prepare_bpf_dispatcher() fills and then copies into bpf_dispatcher->image using bpf_arch_text_copy(). The rel32 offsets emitted by emit_bpf_dispatcher() are calculated against ->image, so ->rw_image does not need to live in the module address range. Allocate ->rw_image with vzalloc() to avoid permissions dance when EXECMEM_BPF will be backed by ROX caches. Using vzalloc() rather than vmalloc() ensures that the memory that bpf_dispatcher_update() unconditionally copies into the executable buffer is zeroed, which is not ideal but still better than random memory returned by the existing bpf_jit_alloc_exec() or plain vmalloc(). Switching from bpf_jit_alloc_exec() to vzalloc() also saves a bit of space in the more scarce module address space. Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20260716-execmem-x86-rox-bpf-v0-v3-1-4e76158c01c5@kernel.org Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-22PM: hibernate: Use %pe to print error pointer valuesRonan Marchal1-2/+2
Use %pe format specifier instead of %ld with PTR_ERR() to print error pointers as a symbolic error name (e.g. -ENOMEM) instead of a raw integer value. Signed-off-by: Ronan Marchal <ronanmarchal29@gmail.com> [ rjw: Subject rewrite ] Link: https://patch.msgid.link/20260615191832.75923-1-ronanmarchal29@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2026-07-22cpufreq: schedutil: Replace sprintf() with sysfs_emit() in sysfs showZhongqiu Han1-1/+1
Use sysfs_emit() instead of sprintf() in rate_limit_us_show(). sysfs_emit() is the preferred API for sysfs output as it provides PAGE_SIZE bounds checking and ensures proper sysfs formatting. No functional change intended. Signed-off-by: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com> Link: https://patch.msgid.link/20260716131546.1159644-1-zhongqiu.han@oss.qualcomm.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2026-07-22cpufreq: schedutil: Publish util hooks only after all sg_cpu are initializedZhongqiu Han1-0/+11
Commit 16a03c71bba0 ("cpufreq: schedutil: Merge initialization code of sg_cpu in single loop") merged the per-CPU initialization and the utilization-hook registration into a single loop in sugov_start(). For a shared cpufreq policy this re-introduces the race originally fixed by commit ab2f7cf141aa ("cpufreq: schedutil: Fix sugov_start() versus sugov_update_shared() race"). The scheduler's util path reaches the hook under RCU-sched and never takes policy->rwsem, so the rwsem held across sugov_start() cannot serialize the two. Once the first CPU's hook is published, sugov_update_shared() may run and, via sugov_next_freq_shared(), read/write each sibling sugov_cpu (iowait_boost, util, bw_min, ...) concurrently with the memset() still initializing them, with no lock common to both sides: the update side holds sg_policy->update_lock while the init side holds only policy->rwsem, which the scheduler's util path never takes. The walk only accesses scalar members, never a pointer like ->sg_policy, so it does not crash today; it merely uses stale (or zero on first start) values that skew the frequency selection and tracepoints. It is still a genuine data race, and a latent crash once any pointer member is dereferenced there. Restore the two-phase approach: initialize all per-CPU structures first, and only then publish the per-CPU utilization update hooks. Fixes: 16a03c71bba0 ("cpufreq: schedutil: Merge initialization code of sg_cpu in single loop") Cc: stable@vger.kernel.org Signed-off-by: Zhongqiu Han <zhongqiu.han@oss.qualcomm.com> Reviewed-by: Christian Loehle <christian.loehle@arm.com> Link: https://patch.msgid.link/20260716115159.848403-1-zhongqiu.han@oss.qualcomm.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2026-07-22PM: hibernate: Remove kernel-doc markings from helper descriptionsAdi Nata1-21/+21
Several helpers in snapshot.c are introduced with kernel-doc (/**) comment blocks but do not describe their parameters with @param tags.This emits warnings when building with extra warnings enabled (make W=1), for example: kernel/power/snapshot.c:469: warning: Function parameter or member 'zone' not described in 'add_rtree_block' kernel/power/snapshot.c:469: warning: Function parameter or member 'gfp_mask' not described in 'add_rtree_block' kernel/power/snapshot.c:469: warning: Function parameter or member 'safe_needed' not described in 'add_rtree_block' kernel/power/snapshot.c:469: warning: Function parameter or member 'ca' not described in 'add_rtree_block' These are file-local implementation details, not part of the exported kernel API documented under Documentation/. Replace the kernel-doc markers with plain block comments for the affected functions. Properly documented symbols such as alloc_rtree_node(), snapshot_read_next() and snapshot_write_next() remain unchanged. Signed-off-by: Adi Nata <adinata.softwareengineer@gmail.com> [ rjw: Subject rewrite ] Link: https://patch.msgid.link/20260609231626.38839-1-adinata.softwareengineer@gmail.com Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2026-07-21sched_ext: Build the cid tables privately and publish them with RCUTejun Heo5-139/+273
The cid tables are visible to the cid kfuncs while being modified: the first enable publishes the global pointers before filling them, ops.init_cids() overrides rewrite them in place, and re-enables rebuild them in place. A racing TRACING or SYSCALL program can read unfilled entries, including uninitialized memory in the kmalloc'd tables, or torn topo updates. Tie the tables' lifetimes to the root sched instead: each root enable builds a fresh set privately and publishes the per-table __rcu globals once the layout is final, and root disable unpublishes and RCU-frees the set. A non-NULL global is now always a fully built table which stays valid for the reader's RCU read section, and lookups stay two loads. Kfuncs treat NULL as no-mapping, also after the scheduler exits instead of reporting the stale last mapping. The cid kfuncs are available whether the root scheduler is cid-form or cpu-form, the latter to allow gradual migration to cids. Every root therefore builds and publishes a default mapping. Every reader must either be gated on scheduler liveness or NULL-check inside an RCU read section. Fix the two kfuncs that were neither: scx_bpf_this_cid() read the table with no RCU or preemption protection and scx_bpf_task_cid() relied on KF_RCU, which doesn't put a sleepable program in an RCU read section. The hotplug callbacks are instead serialized by retiring the tables inside the cpus_read_lock() section that clears scx_root. v2: Document why every root builds the tables (desc + cid.c comment). Reported-by: Andrea Righi <arighi@nvidia.com> Closes: https://lore.kernel.org/r/al3tLtPZZkFjMveK@gpd4 Reviewed-by: Andrea Righi <arighi@nvidia.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-07-21sched_ext: Drop unused scx_cpumask_to_cmask()Tejun Heo2-22/+0
scx_cpumask_to_cmask() has no callers. Reviewed-by: Andrea Righi <arighi@nvidia.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-07-21sched_ext: Skip the default CPU selection while bypassingTejun Heo1-2/+13
select_task_rq_scx() falls into the default path when the scheduler has no ops.select_cpu or is bypassing. There it calls scx_select_cpu_dfl() and direct-dispatches to the picked CPU's local DSQ. While bypassing, neither does anything: the enqueue path routes the task to a bypass DSQ before consulting the direct-dispatch target, so the direct dispatch never happens, and the CPU pick at most shifts which CPU's bypass DSQ receives the task. Worse, when the scheduler does its own idle tracking, the built-in idle cpumasks the pick consults are not even updated, so it doesn't work anyway. Return prev_cpu without the default selection while bypassing and let the bypass enqueue place the task. Reviewed-by: Andrea Righi <arighi@nvidia.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-07-21sched_ext: Blame the DSQ's owning scheduler for a runnable stallTejun Heo1-0/+11
check_rq_for_timeouts() blames a runnable stall on the task's owner. Under a sub-scheduler hierarchy the stalled task can be sitting on a DSQ that a different scheduler has to drain, e.g. an ancestor's bypass DSQ while the owner is bypassing. The drainer then escapes blame while the owner is exited, and when the owner's exit is already claimed, nothing actionable is reported at all. Blame the DSQ's owning scheduler instead. The local DSQ is consumed by the cpu itself and keeps blame on the owner. Detection keeps the owner's timeout and single-scheduler behavior is unchanged. Reviewed-by: Andrea Righi <arighi@nvidia.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-07-21bpf: Mark bpf_refcount field as uniqueKumar Kartikeya Dwivedi1-1/+1
BPF_REFCOUNT is not marked as a unique field, while it should be. Fix this oversight. Fixes: d54730b50bae ("bpf: Introduce opaque bpf_refcount struct and add btf_record plumbing") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://patch.msgid.link/20260719153634.2908692-4-memxor@gmail.com Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-07-21bpf: Preserve unique-field state across nested structsKumar Kartikeya Dwivedi1-12/+14
btf_find_struct_field() initializes a fresh seen mask for every recursive descent. Unique special fields in different levels of the same aggregate therefore do not see one another. The duplicate fields can reach btf_parse_fields(), where they trigger an invariant WARN_ON_ONCE(). A crafted user BTF can consequently trigger the warning before map creation checks capabilities. Initialize the seen mask once in btf_find_field() and pass the same pointer through struct, datasec, and nested-struct walks. This gives the entire field traversal one shared uniqueness state. Fixes: 64e8ee814819 ("bpf: look into the types of the fields of a struct type recursively.") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://patch.msgid.link/20260719153634.2908692-3-memxor@gmail.com Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-07-21bpf: Fix offset warn check for bpf_res_spin_lockKumar Kartikeya Dwivedi1-1/+1
Sashiko pointed out correctly that the case statement for BPF_RES_SPIN_LOCK incorrectly checks offset for BPF_SPIN_LOCK. Fix it by checking res_spin_lock_off instead. Fixes: 0de2046137f9 ("bpf: Implement verifier support for rqspinlock") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://patch.msgid.link/20260719153634.2908692-2-memxor@gmail.com Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
2026-07-21bpf: Zero queue and stack outputs on lock failureKumar Kartikeya Dwivedi1-2/+6
Queue and stack pop/peek helpers accept an uninitialized output buffer because the verifier expects the helper to initialize it. The empty-map error path clears the buffer, but a failed lock acquisition returns -EBUSY without writing it. Clear the output before returning -EBUSY so BPF programs cannot observe uninitialized stack contents after a failed helper call. Fixes: a34a9f1a19af ("bpf: Avoid deadlock when using queue and stack maps from NMI") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/bpf/20260719125419.1782196-1-memxor@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-21cgroup/dmem: accept only one region per limit writeEric Chanudet1-44/+25
Accept only one "region value" pair entry for the dmem.max, dmem.min, dmem.low files. This changes the UAPI that otherwise accepted multiple lines for setting multiple entries in one write. No existing user is known to rely on writing multiple regions in a single write. Processing multiple regions in dmemcg_limit_write() could quietly change first limits before failing on a later one and returning an error to the writer, with no indication some changes occurred. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Eric Chanudet <echanude@redhat.com> Reviewed-by: Maxime Ripard <mripard@kernel.org> Reviewed-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com> Tested-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com> Reviewed-by: Natalie Vock <natalie.vock@gmx.de> Link: https://patch.msgid.link/20260608-cgroup-dmem-write-single-region-v2-1-b0cd6c4ccf1b@redhat.com Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>
2026-07-21tracing/probes: Fix extra whitespace in trace_probe_kernel.hMasami Hiramatsu (Google)1-1/+1
Clean up extra space after '=' in fetch_store_strlen_user(). Link: https://lore.kernel.org/all/178454430235.296567.9486503882045148585.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/kprobe: Remove redundant memset in kprobe_perf_func()Masami Hiramatsu (Google)1-1/+0
kprobe_perf_func() calls memset(&entry[1], 0, dsize) prior to calling store_trace_args(). store_trace_args() populates the entry buffer and handles dynamic data fields. Remove this redundant memset call to align with kretprobe_perf_func() and other probe perf functions. Link: https://lore.kernel.org/all/178454429309.296567.17379087988750549247.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/fprobe: Remove redundant memset in fentry_perf_func()Masami Hiramatsu (Google)1-1/+0
fentry_perf_func() calls memset(&entry[1], 0, dsize) prior to calling store_trace_args(). store_trace_args() populates the entry buffer and handles dynamic data fields. Furthermore, passing dsize (the dynamic data byte length) to memset at &entry[1] (the start of fixed trace arguments) is inaccurate as it zeroes from the fixed args area rather than the dynamic data region. Remove this redundant memset call to align with fexit_perf_func() and other probe perf functions. Link: https://lore.kernel.org/all/178454428366.296567.16465331441301815980.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/fprobe: Remove redundant snprintf in trace_fprobe_match_command_head()Masami Hiramatsu (Google)1-4/+1
trace_fprobe_match_command_head() copies trace_fprobe_symbol(tf) into a local buffer 'buf' of size MAX_COMMON_HEAD_LEN + 1 using snprintf before comparing with argv[0]. Since trace_fprobe_symbol(tf) already returns a null-terminated string, comparing it directly with argv[0] via strcmp() avoids stack buffer usage and potential symbol truncation at MAX_COMMON_HEAD_LEN. Link: https://lore.kernel.org/all/178454427449.296567.12336315661120939938.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/probes: Simplify BTF_KIND_PTR case in fetch_type_from_btf_type()Masami Hiramatsu (Google)1-4/+1
Use a ternary operator for checking IS_ENABLED(CONFIG_64BIT) in the BTF_KIND_PTR case of fetch_type_from_btf_type() to simplify the code. Link: https://lore.kernel.org/all/178454426554.296567.17700307233923830044.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/probes: Cleanup pointer arithmetic in store_trace_entry_data()Masami Hiramatsu (Google)1-1/+1
In store_trace_entry_data(), edata is cast to unsigned long for pointer offset arithmetic before being cast back to unsigned long *. Cast edata to u8 * instead. Link: https://lore.kernel.org/all/178454425622.296567.16952341966130280432.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/probes: Remove unused parameter from parse_probe_var_retval()Masami Hiramatsu (Google)1-2/+2
The parameter 'arg' in parse_probe_var_retval() is unused. Remove it and update its caller accordingly. Link: https://lore.kernel.org/all/178454424711.296567.15352344258939682112.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/probes: Remove redundant bounds check in trace_probe_compare_arg_type()Masami Hiramatsu (Google)1-4/+3
In trace_probe_compare_arg_type(), prior to entering the comparison loop, a->nr_args and b->nr_args are checked for equality. Since the loop condition is i < a->nr_args, i is guaranteed to be less than b->nr_args inside the loop. Remove the redundant (b->nr_args <= i) check. Link: https://lore.kernel.org/all/178454423769.296567.6694636865644203423.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/probes: Remove redundant boolean conversion in trace_probe_has_single_file()Masami Hiramatsu (Google)1-1/+1
list_is_singular() returns a boolean value, so the double negation (!!) in trace_probe_has_single_file() is redundant. Remove it. Link: https://lore.kernel.org/all/178454422826.296567.4382363406595169533.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/probes: Remove duplicate MAX_ARRAY_LEN macro definitionMasami Hiramatsu (Google)1-1/+0
MAX_ARRAY_LEN is defined twice in trace_probe.h. Remove the redundant definition. Link: https://lore.kernel.org/all/178454421926.296567.6649983666070787570.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/eprobe: Fix exact system name matching in eprobe_dyn_event_match()Masami Hiramatsu (Google)1-1/+2
eprobe_dyn_event_match() checks if the target event system in argv[0] matches ep->event_system using strncmp(ep->event_system, argv[0], len). However, if ep->event_system is longer than len (e.g. "eprobes" vs "ep/event"), strncmp() still returns 0 because the first len characters match. Check that ep->event_system[len] is '\0' to ensure exact system name matching. Link: https://lore.kernel.org/all/178454235856.290363.14872590900774231133.stgit@devnote2/ Fixes: 7d5fda1c841f ("tracing: Fix event probe removal from dynamic events") Cc: stable@vger.kernel.org Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/probes: Fix potential underflow in LEN_OR_ZERO macroMasami Hiramatsu (Google)1-1/+1
In __set_print_fmt(), LEN_OR_ZERO is defined as (len ? len - pos : 0). If len is non-zero but smaller than pos, len - pos evaluates to a negative integer. When passed as a size argument to snprintf(), this negative value is cast to a large unsigned size_t, bypassing buffer size limits. Ensure len > pos before subtracting to avoid integer underflow. Link: https://lore.kernel.org/all/178454234934.290363.15247317871499514139.stgit@devnote2/ Fixes: 5bf652aaf46c ("tracing/probes: Integrate duplicate set_print_fmt()") Cc: stable@vger.kernel.org Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/probes: Prevent out-of-bounds write in __trace_probe_log_err()Masami Hiramatsu (Google)1-1/+1
If trace_probe_log.argc is 0 in __trace_probe_log_err(), the loop constructing the command string will not execute and p will remain equal to command. Writing to *(p - 1) will cause an out-of-bounds access before command. This should not happen, but better to be treated. Reject if trace_probe_log.argc is 0. Link: https://lore.kernel.org/all/178454233992.290363.18323091580600697731.stgit@devnote2/ Fixes: ab105a4fb894 ("tracing: Use tracing error_log with probe events") Cc: stable@vger.kernel.org Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21tracing/probes: Avoid temporary buffer truncation in trace_probe_match_command_args()Masami Hiramatsu (Google)1-4/+5
In trace_probe_match_command_args(), a stack buffer buf[MAX_ARGSTR_LEN + 1] (256 bytes) is used to format "<name>=<comm>". However, since name can be up to 32 bytes (MAX_ARG_NAME_LEN) and comm up to 255 bytes (MAX_ARGSTR_LEN), the formatted string can exceed 256 bytes and get truncated by snprintf(), causing spurious argument matching failures. Instead of formatting into a temporary buffer on stack, compare the argument name, the '=' delimiter, and the comm expression directly. Link: https://lore.kernel.org/all/178454233010.290363.10428767141343428804.stgit@devnote2/ Fixes: eb5bf81330a7 ("tracing/kprobe: Add per-probe delete from event") Cc: stable@vger.kernel.org Assisted-by: Antigravity:gemini-3.5-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-20entry: Rework trace_syscall_enter()Thomas Gleixner1-7/+2
Reread the syscall number from pt_regs and stop returning the eventually modified syscall number. That moves the reread to the end of syscall_trace_enter() and prepares for moving it to the call site. No functional change. Signed-off-by: Thomas Gleixner <tglx@kernel.org> Tested-by: Michal Suchánek <msuchanek@suse.de> Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com> Link: https://patch.msgid.link/20260712141346.639115923@kernel.org
2026-07-20entry: Rework syscall_audit_enter()Thomas Gleixner1-0/+12
Move it out of line and let it reread the syscall number on it's own. That makes the low level entry code denser and allows to move the reread to the call site of syscall_trace_enter() once the tracer is fixed up. To prevent the compiler from putting audit_context() out of line and thereby breaking dead code elimination, mark audit_context() __always_inline. Signed-off-by: Thomas Gleixner <tglx@kernel.org> Tested-by: Michal Suchánek <msuchanek@suse.de> Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com> Link: https://patch.msgid.link/20260712141346.576865340@kernel.org
2026-07-20kcsan: avoid unintended access checking in NMIsMarco Elver1-2/+10
If a watcher deliberately disables interrupts (either by user choice, or because we're dealing with a scoped reordered access) to avoid detecting any data races in interrupts, NMIs are still able to fire. When we set up a watchpoint on a scoped reordered access, we disabled interrupts because the same CPU cannot observe reordering of its own accesses. To ensure we observe no false positives from NMIs, disable access checking for interrupt contexts as well. Fixes: 69562e4983d9 ("kcsan: Add core support for a subset of weak memory modeling") Signed-off-by: Marco Elver <elver@google.com>
2026-07-20timers/migration: Fix bad line kernel-doc warning in struct tmigr_cpuBabanpreet Singh1-1/+1
Running kernel-doc on timer_migration.h reports: Warning: kernel/time/timer_migration.h:105 bad line: The empty line separating the @available paragraph from the @idle member documentation in the struct tmigr_cpu kernel-doc block lacks the " *" line prefix that kernel-doc requires on every line inside a block. The header is not scanned by the build-time kernel-doc checks, so the warning only shows up when kernel-doc is invoked on the file directly. Add the missing prefix. The empty line was introduced when the @available documentation was expanded by commit 45a13ba52c82 ("timers/migration: Update stale @online doc to @available"). No functional change. Signed-off-by: Babanpreet Singh <bbnpreetsingh@gmail.com> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Assisted-by: Claude:claude-sonnet-5 Link: https://patch.msgid.link/20260717035947.7-1-bbnpreetsingh@gmail.com
2026-07-20rv: Simplify hybrid automata monitors's clock variablesNam Cao2-17/+3
Hybrid automata monitors's clock variables have two different representations: - The invariant representation, which is the timestamp when the invariant expires - The guard representation, which is the timestamp when the clock is last reset This dual representation makes the logic quite difficult to follow (well, at least for me). It also complicates the monitors and the generation tool, as it requires conversion back and forth between the representation. Simplify by using the clock variables for a single purpose: storing the time stamp since the clock is last reset. This also allows simplifying rvgen, which will be done in a follow-up commit. Reviewed-by: Gabriele Monaco <gmonaco@redhat.com> Signed-off-by: Nam Cao <namcao@linutronix.de> Link: https://lore.kernel.org/r/c0f600dcbf3d8b487c944406851a39146f4d91fa.1781847583.git.namcao@linutronix.de Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2026-07-20genirq/msi: Move misplaced EXPORT_SYMBOL_GPL for msi_domain_free_irqs_all()Li RongQing1-1/+1
EXPORT_SYMBOL_GPL(msi_domain_free_irqs_all) was mistakenly placed after msi_domain_free_irqs_range() instead of after its intended function msi_domain_free_irqs_all(). Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: Thomas Gleixner <tglx@kernel.org> Reviewed-by: Radu Rendec <radu@rendec.net> Link: https://patch.msgid.link/20260717143157.1718-1-lirongqing@baidu.com
2026-07-19sched_ext: Rename the cid-form cgroup ops to cpuctl_*Tejun Heo2-31/+30
Two unrelated things go by "cgroup" in the cid form. Sub-schedulers attach to cgroups, and the cgroup_*() ops deliver cpu controller events. While the ops names suggest cgroup2 hierarchy, they actually operate on the cpu controller. Rename them to cpuctl_* in struct sched_ext_ops_cid, which has no users outside scx_qmap yet. The cpu form is deployed ABI and keeps the old names. The layout is unchanged and the kernel keeps calling through the cpu-form union view. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-07-19sched_ext: Hand over cgroups at sub-scheduler enable/disableTejun Heo3-13/+237
Sub-schedulers don't get cgroups yet: every task_group is inited on the root sched and the routing added by the previous patches always resolves to it. Add the handover: an enabling sub-scheduler takes over the cgroups in its subtree and a disabling one returns them to its parent. scx_cgroup_claim_subtree() runs while the sub enables, after the subtree's cgrp->scx_sched's are set and before any task is claimed. It inits each subtree task_group on the sub, exits it from the parent and updates tg->scx.sched. A failed ops.cgroup_init() unwinds the sub-side inits and aborts the enable with the parent untouched. Disabling reverses it with scx_cgroup_return_subtree(): exit each cgroup from the sub, then re-init it on the parent with the current tg->scx.* values, resyncing weight and bandwidth changes made while the sub had it. When a re-init fails, the parent is failed and the remaining task_groups still transfer uninited and get no cgroup ops - the same punting done for tasks. The dying parent's own disable moves them onward. The handover walks include dying but not yet offlined task_groups, the same as root's bulk walks: a removed cgroup keeps hosting scheduling events until its dying tasks finish their final context switches, and its ops.cgroup_exit() must follow the last of them. tg on/offlining is excluded through cgroup_lock(), so either ordering against an rmdir of a subtree cgroup delivers balanced init/exit pairs. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-07-19sched_ext: Deliver cgroup ops to each task_group's schedTejun Heo2-47/+144
With sub-schedulers claiming cgroup subtrees, cgroup ops must be delivered to each task_group's sched rather than always to root. Add tg->scx.sched to track which sched initialized the task_group. It is set and cleared together with SCX_TG_INITED. Deliver the ops accordingly: - ops.cgroup_exit() goes to the sched whose ops.cgroup_init() it pairs with. - ops.cgroup_prep_move/move/cancel_move() go to the task's sched, and only for moves that don't re-home the task. A re-homing move is reported through the ops.exit_task/init_task() pair instead. The cgroups passed to the move ops can be outside the sched's inited set as the cpu controller can be coarser than the sub-scheduler topology. - Knobs of a cgroup belong to the parent, so ops.set_weight/idle/bandwidth() go to the parent task_group's sched. All task_groups currently resolve to the root sched, so no behavior changes until sub-schedulers start claiming cgroups. While at it, scx_cgroup_init() is restructured so both paths share the recording. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-07-19sched_ext: Re-home tasks on cgroup migrationTejun Heo3-15/+152
A task's sched (p->scx.sched) must match its cgroup's owner (cgrp->scx_sched). cgroup migration breaks the invariant: scx_cgroup_move_task() only fires root's ops.cgroup_move() and never re-homes the task, leading to wrong-sched scheduling and, once the stale sched is freed, a use-after-free. Hook into the new cgroup task migration events and re-home each task whose destination cgroup is owned by a different sched. The events map naturally to the transfer: MIGRATING runs the fallible init for the destination sched, letting it reject the migration the same way ops.cgroup_prep_move() can, MIGRATED does the re-home, which can't fail, and CANCELED undoes the init when the migration falls through. Pre-commit, the task's task_group still reflects the source, so __scx_init_task() grows an explicit cgroup argument for the migration path to hand ops.init_task() the destination cgroup. Signed-off-by: Tejun Heo <tj@kernel.org> Closes: https://lore.kernel.org/r/alnxrsexEe_nQwqL@gpd4 Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-07-19sched_ext: Relocate scx_cgroup_enabledTejun Heo2-6/+13
scx_cgroup_enabled is in the CONFIG_EXT_GROUP_SCHED block. The upcoming cgroup migration re-homing needs the gate outside the block. Move the definition and flag flips outside CONFIG_EXT_GROUP_SCHED. No functional changes. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-07-19sched_ext: Factor out scx_rehome_task() and scx_punt_task()Tejun Heo1-28/+56
Factor out scx_rehome_task() and scx_punt_task() from the sub-disable re-home loop and scx_fail_parent(). The upcoming cgroup migration re-homing also needs scx_rehome_task(). No functional changes. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-07-19cgroup: Add cgroup_task_notifier and task migration eventsTejun Heo1-9/+84
A subsystem can attach to the cgroup hierarchy itself, independent of which controllers are enabled where - BPF hooks already behave this way and sched_ext sub-schedulers do too. Controller callbacks can't track task migrations for them: sched_ext must re-home a task whose migration crosses a sub-scheduler boundary, but the cpu controller's attach callbacks fire only when the task_group changes and miss moves whenever the controller topology is coarser than the sub-scheduler topology. Add cgroup_task_notifier with per-task migration events mirroring the can_attach/attach/cancel_attach phases so that a consumer which prepares per-task state can also veto a migration: CGROUP_TASK_MIGRATING fires pre-commit, CGROUP_TASK_MIGRATED post-commit and CGROUP_TASK_MIGRATE_CANCELED unwinds a failed migration. Only migrations that change a task's dfl cgroup are reported. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Andrea Righi <arighi@nvidia.com>
2026-07-19bpf: Disallow interpreter fallback for BPF_ADDR_PERCPU insnLeon Hwang1-0/+5
The BPF_MOV64_PERCPU_REG insn requires JIT to emit native code to for 'dst_reg = src_reg + <percpu_base_off>'. However, the interpreter ignores the 'off' at its ALU64_MOV_X label. The 'off' indicates the insn is BPF_MOV64_PERCPU_REG insn. Then, when the interpreter loads memory from the register, it will hit a page fault. [ 2.545572] BUG: unable to handle page fault for address: ffffffffacaaf034 [ 2.546485] #PF: supervisor read access in kernel mode [ 2.547167] #PF: error_code(0x0000) - not-present page [ 2.547850] PGD 134e63067 P4D 134e63067 PUD 134e64063 PMD 10021c063 PTE 800ffffeca550062 [ 2.548912] Oops: Oops: 0000 [#1] SMP PTI Set jit_required as true in order to disallow interpreter fallback in core.c::__bpf_prog_select_runtime(), if any BPF_ADDR_PERCPU insn is patched to the prog. BTW, rename the helper bpf_map_supports_cpu_flags() to bpf_map_is_percpu_map(). Fixes: 7bdbf7446305 ("bpf: add special internal-only MOV instruction to resolve per-CPU addrs") Signed-off-by: Leon Hwang <leon.hwang@linux.dev> Link: https://lore.kernel.org/bpf/20260715141122.15783-4-leon.hwang@linux.dev Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>