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2026-07-22bpf: alloc_prog_pack(): Skip ROX management for already ROX memoryMike Rapoport (Microsoft)
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)
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)
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 Marchal
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 Han
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 Han
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 Nata
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 Heo
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 Heo
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 Heo
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 Heo
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 Dwivedi
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 Dwivedi
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 Dwivedi
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 Dwivedi
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 Chanudet
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)
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)
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)
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)
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)
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)
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)
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)
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 ↵Masami Hiramatsu (Google)
trace_probe_has_single_file() 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)
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)
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)
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)
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 ↵Masami Hiramatsu (Google)
trace_probe_match_command_args() 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 Gleixner
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 Gleixner
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 Elver
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 Singh
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 Cao
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 RongQing
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 Heo
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 Heo
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 Heo
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 Heo
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 Heo
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 Heo
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 Heo
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 Hwang
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>
2026-07-19bpf: Disallow interpreter fallback for gotox insnLeon Hwang
The interpreter does not recognize the BPF_JMP|BPF_JA|BPF_X insn, which is used for insn_array map. Thereafter, it would hit the BUG_ON() in ___bpf_prog_run() at run time. [ 2.563726] BPF interpreter: unknown opcode 0d (imm: 0x0) [ 2.564557] ------------[ cut here ]------------ [ 2.565206] kernel BUG at kernel/bpf/core.c:2349! [ 2.565882] Oops: invalid opcode: 0000 [#1] SMP PTI Set jit_required as true when insn_array map is used in the prog in order to disallow interpreter fallback for gotox insn in core.c::__bpf_prog_select_runtime(). Fixes: 493d9e0d6083 ("bpf, x86: add support for indirect jumps") Signed-off-by: Leon Hwang <leon.hwang@linux.dev> Link: https://lore.kernel.org/bpf/20260715141122.15783-3-leon.hwang@linux.dev Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-19bpf: Disallow interpreter fallback for arena-related insnsLeon Hwang
Since the interpreter does not support the arena-related insns, interpreter fallback should not be allowed for these insns in core.c::__bpf_prog_select_runtime(). Currently, when the interpreter executes the arena ST/LDX/STX insns, it would hit the BUG_ON() in ___bpf_prog_run() at run time. [ 2.579196] BPF interpreter: unknown opcode a2 (imm: 0x0) [ 2.579998] ------------[ cut here ]------------ [ 2.580652] kernel BUG at kernel/bpf/core.c:2349! [ 2.581314] Oops: invalid opcode: 0000 [#1] SMP PTI Set jit_required as true when arena map is used in the prog to disallow interpreter fallback for arena-related insns. Fixes: 6082b6c328b5 ("bpf: Recognize addr_space_cast instruction in the verifier.") Signed-off-by: Leon Hwang <leon.hwang@linux.dev> Link: https://lore.kernel.org/bpf/20260715141122.15783-2-leon.hwang@linux.dev Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-19bpf: Reject arena frees below the arena baseYiyang Chen
bpf_arena_free_pages() accepts scalar arena addresses. The runtime masks the address to the low 32 bits and reconstructs a full user address from the arena base before returning the range to the arena free tree. When the scalar value is below the low 32 bits of the arena base, full_uaddr falls below user_vm_start. The existing upper-end clipping then turns this into an out-of-range free-tree offset. A later allocation can reuse that offset and return an address below the arena mapping. Reject such frees before computing the clipped range. Fixes: 317460317a02a ("bpf: Introduce bpf_arena.") Signed-off-by: Yiyang Chen <chenyy23@mails.tsinghua.edu.cn> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/bpf/20260717-c10-031-public-bpf-next-v2-b4-v2-1-54b555443a7c@mails.tsinghua.edu.cn Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-19bpf: Add memory usage for arenaJiayuan Chen
arena is the only map type whose map_mem_usage() still returns 0, so "bpftool map show" and fdinfo always showed 0 memlock for an arena no matter how many pages it had. Count the pages that are actually mapped into the arena: bump a counter in apply_range_set_cb() when a page goes in and drop it in apply_range_clear_cb() when a page goes out, both under the arena spinlock. map_mem_usage() then just returns nr_pages << PAGE_SHIFT. Only real data pages are counted, not the scratch page. Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/bpf/20260717114117.350851-3-jiayuan.chen@linux.dev Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-19bpf: Pass arena instead of scratch_page to the pte callbacksJiayuan Chen
Replace the scratch_page field in the pte-callback data with the arena pointer; later patches use other arena fields from these callbacks. No functional change. Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev> Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com> Link: https://lore.kernel.org/bpf/20260717114117.350851-2-jiayuan.chen@linux.dev Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-17Merge branch 'for-7.2-fixes' into for-7.3Tejun Heo
Pull to receive: 477869bfafea ("sched_ext: Reject setting disallow from init_task outside the enable path") 5f8b69642d18 ("sched_ext: Take cgroup_lock() first in scx_cgroup_lock()") 8c13364db9c9 ("sched_ext: Skip sub-disable teardown for never-linked sub-schedulers") 5cdc92859809 ("sched_ext: Don't enable non-ext tasks in the sub-sched task loops") as dependencies for the upcoming cgroup migration patchset and to resolve the conflicts with the ext.c/sub.c split on for-7.3. 5f8b69642d18 comments scx_cgroup_lock() which for-7.3 exported for sub.c. Resolved by keeping the exported version with the comment. 8c13364db9c9 and 5cdc92859809 patch the pre-split sub-sched enable and disable paths in ext.c which for-7.3 moved to sub.c. Resolved by applying the never-linked teardown skip and the class gates to sub.c. Signed-off-by: Tejun Heo <tj@kernel.org>