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2026-09-20landlock: Fix tracepoint contract documentationMickaël Salaün1-12/+18
The tracepoint documentation claims that denial and lifecycle events expose every input needed to reproduce a verdict. Instead document how denial, ruleset, and domain events identify the denying policy, checked operation and object, and reason for denial. Direct consumers to generic tracepoints for additional operational context. State the reconstruction limits: IDs are boot-local, rule checks have no request ID, and exported records may be lost or cross-CPU reordered. Also replace the incorrect BPF_RAW_TRACEPOINT guidance with libbpf SEC("tp_btf/...") attachment and refer consumers to the event prototypes for callback argument layouts. Cc: Günther Noack <gnoack@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Link: https://patch.msgid.link/20260918185036.608651-10-mic@digikod.net Signed-off-by: Mickaël Salaün <mic@digikod.net>
2026-09-20landlock: Fix rule tracepoint contextMickaël Salaün1-11/+11
Name each event after the identity it reports. Add-rule events describe UAPI rule insertion, so rename them after LANDLOCK_RULE_PATH_BENEATH and LANDLOCK_RULE_NET_PORT. Check-rule events describe matches in internal rule trees, so rename them after LANDLOCK_KEY_INODE and LANDLOCK_KEY_NET_PORT. This remains accurate if multiple UAPI rule types share one lookup and stored rule. Keep denial event names based on filesystem and network families because they describe final access decisions. Use u64 for growable access masks passed by value to add-rule and check-rule typed BTF callbacks. CO-RE can relocate pointer-reached fields, but it cannot widen a scalar callback slot declared by a BPF program. Keep native access_mask_t for internal state and trace records. For add-rule callbacks, report the normalized per-call contribution passed to landlock_insert_rule() and expose the complete validated flags value. Put the ruleset and flags first as a common invocation prefix. This distinguishes duplicate and effective-zero additions without recovering arguments from saved syscall registers. Cc: Günther Noack <gnoack@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Fixes: 63747c94774d ("landlock: Add landlock_add_rule_fs and landlock_add_rule_net tracepoints") Fixes: 3f1f106e4c14 ("landlock: Add tracepoints for rule checking") Link: https://patch.msgid.link/20260918185036.608651-4-mic@digikod.net Signed-off-by: Mickaël Salaün <mic@digikod.net>
2026-08-22Merge tag 'perf-tools-for-v7.3-2026-08-21' of ↵Linus Torvalds1-14/+14
git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools Pull perf tools updates from Namhyung Kim: "perf c2c: - Add 'function view' in perf c2c report TUI (switched by pressing 'TAB' in the cacheline view) to organize samples around functions rather than cachelines in 3-level hierarchy: Level 1: Read-side function (sorted by estimated Cycles %) Level 2: Contending writer functions (sorted by Store count) Level 3: Shared cacheline addresses Users can navigate the entries and fold/unfold using 'e' key. An example output would look like below: Shared Data Functions Table (19 entries, sorted on Cycles %) Cycles Store % count Function / Contending function / Cacheline ---------------------------------------------------------------------- + 35.67% 876 + [k] cpupri_set + 24.31% 424 + [k] pull_rt_task - 16.53% 555 - [k] dequeue_pushable_task 145 - [k] pull_rt_task 145 0xff2d0082809da080 139 - [k] enqueue_pushable_task 70 0xff2d00a2071f9640 69 0xff2d0082809da000 python module support: - Extend "perf" python module so that it can be fully functional. The goal is to run scripts directly, not by 'perf script' command. This would give better performance as well as more control to build standalone programs with UI. - Add LiveSession helper (perf_live.py) to enable live event collection directly from Python using perf.evlist and perf.parse_events. perf stat: - Add --hide-zero-events option to suppress zero-count events - Reject conflicting --field-separator and --json-output options - Fix duplicate event output with --for-each-cgroup perf sched latency: - Add -H/--histogram and --hist-mode (log|linear) options to show scheduler wait latency histograms - Add --time option to filter analysis by time span in 'perf sched latency' ARM CoreSight: - Synthesize callchains for instruction samples from CoreSight trace using thread stack ('--itrace=g...') - Support call indentation ('perf script -F +callindent') to display call depth hierarchy on branch samples - Decode ETE (Embedded Trace Extension) exception packets Build system: - Add 'make install-build-deps' target to install required packages - Parallelize JSON and metric pre-computation in jevents.py for faster builds Vendor event/metric updates: - Add Intel Nova Lake events and update tables for existing models - Update AMD Zen 5 and Zen 6 core events - Update Arm64 Tegra410 metrics and PowerPC hcalls Internal changes and fixes: - Harden trace-event and synthetic event parsing against corrupted data - Fix unwinding of multi-threaded processes in libdw unwinder - Fix memory leaks in various commands and python bindings - Speed up 'perf test' shell tests" * tag 'perf-tools-for-v7.3-2026-08-21' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (232 commits) perf vendor events arm64: Fix Tegra410 Olympus event 0x0197 perf vendor events arm64: fix swapped MetricGroup for Tegra410 L1 prefetcher metrics perf evlist: Warn when 'sleep' workload is used without system-wide (-a) option perf c2c: document function view in perf-c2c man page perf c2c: add function view browser UI and cacheline detail perf c2c: build and finalize the function view hierarchy perf c2c: add function view hierarchy entry creation perf c2c: add function view stats merge and memory management perf c2c: add HPP list parsing for function view columns perf c2c: add column rendering for function view perf c2c: add function view model skeleton perf c2c: extract shared data structures into util/c2c.h perf test sample-parsing: Validate PERF_FORMAT_GROUP values without LOST perf dso: Replace assert with runtime check in dso__read_symbol() perf dso: Guard against cache underflow on short reads in dso_cache__memcpy() perf dso: Use stored fd error instead of stale errno in file_read() and file_size() perf dso: Guard close() against invalid fd in dso__decompress_kmodule_path() perf dso: Guard against errno==0 when dso__get_filename() returns NULL perf build: install-build-deps: add RHEL family devel package mapping perf build: Remove leftover feature tests for removed cxx and clang support ...
2026-08-21Merge tag 'landlock-7.3-rc1' of ↵Linus Torvalds2-0/+327
git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux Pull Landlock update from Mickaël Salaün: "This improves observability with Landlock tracepoints support, which required some refactoring for dedicated domain types and common helpers shared with audit code. A LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS flag is also added to improve process-wide domain enforcement consistency. Whiteout files are now correctly handled and tested, and a few other fixes" * tag 'landlock-7.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux: (34 commits) landlock: Document tracepoints selftests/landlock: Add landlock_enforce_domain trace tests selftests/landlock: Add scope and ptrace tracepoint tests selftests/landlock: Add network tracepoint tests selftests/landlock: Add filesystem tracepoint tests selftests/landlock: Add trace event test infrastructure and tests landlock: Add tracepoints for ptrace and scope denials landlock: Add landlock_deny_access_fs and landlock_deny_access_net landlock: Add tracepoints for rule checking landlock: Add landlock_enforce_domain tracepoint landlock: Add create_domain and free_domain tracepoints landlock: Add landlock_add_rule_fs and landlock_add_rule_net tracepoints landlock: Add create_ruleset and free_ruleset tracepoints landlock: Consolidate access-right and scope names in a shared header landlock: Decouple the per-denial logging decision from CONFIG_AUDIT landlock: Split denial logging from audit into common framework landlock: Split struct landlock_domain from struct landlock_ruleset landlock: Move domain query functions to domain.c landlock: Prepare ruleset and domain type split samples/landlock: Add LANDLOCK_RESTRICT_SELF_NO_NEW_PRIVS to sampler ...
2026-08-20Merge tag 'probes-v7.3' of ↵Linus Torvalds5-5/+43
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes updates from Masami Hiramatsu: "BTF typecasting and variable fetch enhancements: - Typecast support across probe events: Extended BTF typecasting syntax (e.g., (STRUCT)PARAM->MEMBER) to kprobes, uprobes, and fprobes on function entry and return - Nested typecasts: Added support for chaining and nesting typecasts up to 3 levels, including casting registers and stack variables - Field specifier option: Added (STRUCT,FIELD) syntax to emulate container_of(), allowing retrieval of parent structures from member pointers - $current variable support: Introduced $current special variable to access the running task_struct via BTF dereferencing - Per-CPU variable access: Added this_cpu_read() and this_cpu_ptr() fetcharg methods to trace CPU-local data safely - Fetcharg bytecode dumper: Added CONFIG_PROBE_EVENTS_DUMP_FETCHARG to dump the compiled fetcharg bytecode instructions as comments in dynamic_events - Extended symbol name handling: Removed the MAX_COMMON_HEAD_LEN limit and extended MAX_ARGSTR_LEN to 256 bytes, enabling probing of long symbols, mangled Rust symbols and complex BTF expressions - eprobe variable syntax: Allowed eprobes to reference event fields directly without requiring a '$' prefix - Cleanup unused parameters, redundant codes, duplicate macros and pointer arithmetic - Use a ternary operator for simplifying fetch_type_from_btf_type() Expanded boot time dynamic probe support: - Add boot-time tracing configuration support for event probes (eprobes), function probes (fprobes), and tracepoint probes (tprobes) - Allow comment lines ('#') in dynamic_events file Optimization, robustness, and cleanups: - Simplify fprobe_remove_ips() by reusing graph and ftrace helpers - Remove __packed attribute from struct __fprobe_header to avoid unaligned memory access penalties on RISC architectures - Remove redundant memset() calls in perf event probe handlers - Replace legacy __ASSEMBLY__ with __ASSEMBLER__ in header files Selftests & refactoring: - Refactor parse_probe_arg() and parse_probe_vars(), and eliminate recursion in probe argument parsing to protect kernel stack depth - Add selftests for BTF typecasts and module probing without module prefixes - Force LC_ALL=C in ftracetest to prevent test failures on localized systems - Refactor btf_type_skip_modifiers() to remove ignored id parameter - Sort ERRORS list in trace_probe.h alphabetically - Fix typo in fprobe docs, and trace_fprobe function name - Rename FETCH_OP_DATA to FETCH_OP_IMMSTR - Make file offset error message probe-agnostic" * tag 'probes-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (37 commits) fprobe: Simplify fprobe_remove_ips() by reusing existing helpers tracing/boot: Add support for eprobe, fprobe, and tprobe events selftests/ftrace: Force C locale in ftracetest tracing/probes: Treating longer symbol name on event comparation docs: trace: fprobe: fix 'thos' spelling tracing/probes: Fix extra whitespace in trace_probe_kernel.h tracing/kprobe: Remove redundant memset in kprobe_perf_func() tracing/fprobe: Remove redundant memset in fentry_perf_func() tracing/fprobe: Remove redundant snprintf in trace_fprobe_match_command_head() tracing/probes: Simplify BTF_KIND_PTR case in fetch_type_from_btf_type() tracing/probes: Cleanup pointer arithmetic in store_trace_entry_data() tracing/probes: Remove unused parameter from parse_probe_var_retval() tracing/probes: Remove redundant bounds check in trace_probe_compare_arg_type() tracing/probes: Remove redundant boolean conversion in trace_probe_has_single_file() tracing/probes: Remove duplicate MAX_ARRAY_LEN macro definition selftests/ftrace: Add test case for a symbol in a module without module name tracing/probes: Eliminate recursion in parse_probe_arg() tracing/probes: Extend max length of argument string tracing/probes: Sort ERRORS list in trace_probe.h alphabetically tracing/probes: Refactor parse_probe_arg() ...
2026-08-19Merge tag 'ftrace-v7.3' of ↵Linus Torvalds1-0/+5
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull ftrace updates from Steven Rostedt: - Deprecrate ftrace_enabled in disabling ftrace The file /proc/sys/kernel/ftrace_enabled was created when ftrace was first introduced back in 2008. It was to be a "kill switch" if something was to go wrong. It was also used as a way to turn off function tracing for the latency tracers that would have it on by default. But in 2013 (Linux 3.10) the option "function-trace" was introduced to disable function tracing for the latency tracers as the "ftrace_enabled" file was considered too big of a hammer and caused too many side effects. When live kernel patching came along, disabling ftrace via the ftrace_enabled file would put the system into an unstable state if a live kernel patch was installed. This created the need to mark some function hooks as "PERMANENT". Now there's a need for BPF usage marked as PERMANENT for the same reasons. The file "ftrace_enabled" usage is no longer viable. It doesn't do what it says it does and there is no reason to use it. Make writing '0' to it a nop and print a message saying its usage is deprecated. The return value of writing '0' is -EOPNOTSUPP so that user space will error on that write (hopefully to inform any developer that it no longer works). Eventually the file should be removed completely, but for now just making it not do anything is the path forward to that. - Update the livepatch tests to handle ftrace_enabled being disabled Because in the past, livepatch was broken by ftrace_enabled being turned off, there's a test case that checks to make sure it still doesn't break. But having the write of '0' return an error caused that test to break. Updated the test to handle the new change. * tag 'ftrace-v7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: selftests/livepatch: update test-ftrace.sh for deprecated ftrace_enabled ftrace: deprecate disabling via ftrace_enabled sysctl
2026-08-17landlock: Document tracepointsMickaël Salaün2-0/+327
Until now, Landlock observability documentation covered only audit records. The tracepoints added by the previous commits introduce a second channel with different semantics (firing regardless of audit configuration and domain log flags, exposing the full ruleset and domain state to eBPF via BTF), which kernel developers, administrators, and userspace tool authors need to discover and compare against audit. Add a dedicated "Landlock Trace Events" reference covering the event categories, enabling events via tracefs, ruleset versioning, eBPF access through BPF_RAW_TRACEPOINT, and the same_exec and logged denial fields (logged being the kernel's audit-logging decision, so a stateless ftrace filter can select the denials audit would record with logged==1). Cross-reference it from the administrator, kernel-internals, and userspace API documents, contrasting tracepoints with audit: when each channel is preferred, what each guarantees, and how NOAUDIT hooks and audit rate limiting affect them. Also document the relational other-party domain fields the scope and ptrace denial tracepoints expose (tracee_domain, target_domain, peer_domain; 0 when the other party is unsandboxed), so a consumer can resolve them against the lifecycle events and reproduce the two-domain verdict. Cc: Günther Noack <gnoack@google.com> Cc: Tingmao Wang <m@maowtm.org> Link: https://patch.msgid.link/20260811094338.288094-20-mic@digikod.net [mic: Update dates] Signed-off-by: Mickaël Salaün <mic@digikod.net>
2026-08-10ftrace: deprecate disabling via ftrace_enabled sysctlAndrey Grodzovsky1-0/+5
Writing 0 to kernel.ftrace_enabled has not reliably disabled ftrace for years (FTRACE_OPS_FL_PERMANENT users already block it, and more callers rely on ftrace always being on). Refuse the write instead of leaving it in an inconsistent "disables some, not all" state: return -EOPNOTSUPP and log a message. Reads and enabling (writing 1) are unaffected. Update the docs to note the deprecation up front. Link: https://patch.msgid.link/20260806153000.4184871-2-andrey.grodzovsky@crowdstrike.com Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@crowdstrike.com> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08tracing/boot: Add support for eprobe, fprobe, and tprobe eventsMasami Hiramatsu (Google)1-3/+15
Boot-time tracing currently supports kprobe-events and synthetic-events under per-event configuration options. Extend boot-time tracing to support newly added dynamic probe types: - event probes (eprobe) under the "eprobes" event group - function probes (fprobe) under the "fprobes" event group - tracepoint probes (tprobe) under the "tracepoints" or "tprobes" event group To support this cleanly, update dyn_event_create() in trace_dynevent.c so that passing NULL as the type parameter delegates to create_dyn_event(), allowing generic creation of any registered dynamic event type from a raw command string. Update Documentation/trace/boottime-trace.rst accordingly to describe the new per-event bootconfig options. Link: https://lore.kernel.org/all/178613905149.259829.18185480460810689421.stgit@devnote2/ Assisted-by: Antigravity:gemini-3.6-flash Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Changes in v3: - Check return values of strscpy() and snprintf() in trace_boot_add_probe_event() to prevent silent buffer truncation when constructing probe event strings. Changes in v2: - Fix raw command detection logic for eprobes, fprobes, and tprobes by requiring ':' or isspace() after type prefix. - Consolidate duplicate loop logic into trace_boot_add_probe_event() helper function.
2026-08-04Documentation/rv: Explain epoll and aborted sleepsChao Liu1-0/+6
epoll_wait() is a valid sleeping reason for real-time tasks because it uses PI-aware locking, but the rtapp sleep monitor documentation only discusses clock_nanosleep() and futexes. Document it. ABORT_SLEEP represents a task restoring TASK_RUNNING before entering the scheduler. Since the task does not actually block, it becomes runnable again without a wakeup sequence unsafe for real-time. Document this behavior. Signed-off-by: Chao Liu <chao.liu@processmission.com> Reviewed-by: Gabriele Monaco <gmonaco@redhat.com> Reviewed-by: Nam Cao <namcao@linutronix.de> Link: https://lore.kernel.org/r/20260729081102.73138-1-chao.liu@processmission.com Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2026-07-31perf hisi-ptt: Fix PTT trace TLP header parsingSizhe Liu1-14/+14
TLP Headers traced by HiSilicon PCIe tune and trace device (PTT) in 4DW format are shown in the document as below: bits [31:30] [ 29:25 ][24][23][22][21][ 20:11 ][ 10:0 ] |-----|---------|---|---|---|---|-------------|-------------| DW0 [ Fmt ][ Type ][T9][T8][TH][SO][ Length ][ Time ] DW1 [ Header DW1 ] DW2 [ Header DW2 ] DW3 [ Header DW3 ] Problem: The DW0 bit field layout of the hisi_ptt_4dw union does not match the actual bit ordering in little-endian memory, causing incorrect field decoding. Test on Kunpeng 930 SOC, generating data flow with `iperf` commands: - server side: iperf -s - client side: iperf -c $ip_addr -t 30 Trace the TLP headers with hisi_ptt on server side at the same time: perf record -e hisi_ptt12_0/type=4,filter=0x05101,direction=2,format=0/ \ --max-size 50M -o perf.data & The trace aims to capture completion TLPs, learn more in the document: https://docs.kernel.org/trace/hisi-ptt.html Decode perf.data with hisi_ptt decoder: perf report -D The hisi_ptt decoder produces the following result: [...perf headers and other information] . ... HISI PTT data: size 8388608 bytes . 00000000: 68 87 20 94 Format 3 Type 1a T9 0 T8 1 TH 1 SO 1 Length 10 Time 4a1 . 00000004: 40 00 00 00 Header DW1 . 00000008: 40 00 01 51 Header DW2 . 0000000c: 00 00 00 00 Header DW3 [...other hisi_ptt TLP headers] According to PCIe r5.0 sec 2.2.1, the Fmt & Type of Cpl/CplD is supposed to be 8b'00001010' / 8b'01001010' However, the Format & Type decoder analyzing result is 8b'01111010'. It does not match field encodings of any TLP. Correct decoder result should be: [...perf headers and other information] . ... HISI PTT data: size 8388608 bytes . 00000000: 94 20 87 68 Format 2 Type a T9 0 T8 0 TH 0 SO 1 Length 10 Time 768 . 00000004: 00 00 00 40 Header DW1 . 00000008: 51 01 00 40 Header DW2 . 0000000c: 00 00 00 00 Header DW3 [...other hisi_ptt TLP headers] To solve the problem: 1. Drop the union and C bitfield struct, store the raw DW value in a plain uint32_t, and extract the fields with FIELD_GET() against GENMASK/BIT masks declared in the header so they can be reused by other translation units. The masks are portable across endianness and compilers. 2. Print all DW hex values in big-endian byte order for readability, matching the bit field layout shown in the 4DW format diagram. 3. Read the DW value with get_unaligned_le32() instead of an unaligned pointer cast, avoiding both strict-aliasing violations and alignment hazards on hosts that do not support unaligned access. Cc: stable@vger.kernel.org Fixes: 5e91e57e6809 ("perf auxtrace arm64: Add support for parsing HiSilicon PCIe Trace packet") Reviewed-by: James Clark <james.clark@linaro.org> Signed-off-by: Sizhe Liu <liusizhe5@huawei.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2026-07-28docs: trace: fprobe: fix 'thos' spellingshaikh.kamal1-1/+1
Fix spelling error reported by codespell: thos -> those. No functional change. Link: https://lore.kernel.org/all/20260726065633.20897-1-shaikhkamal2012@gmail.com/ Signed-off-by: shaikh.kamal <shaikhkamal2012@gmail.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-24rv/rtapp: Add wakeup monitorNam Cao1-0/+20
Add a wakeup monitor to detect a lower-priority task waking up a higher-priority task. The rtapp/sleep monitor already detects this. However, that monitor triggers an error in the context of the wakee task and user only gets the stacktrace of that task. It is also extremely useful to get the stacktrace of the waker task, which this monitor offers. In other words, this monitor complements the rtapp/sleep monitor. Signed-off-by: Nam Cao <namcao@linutronix.de> Reviewed-by: Gabriele Monaco <gmonaco@redhat.com> Link: https://lore.kernel.org/r/ba5658fa13e49ada466b84a2c211f233037180b5.1781852967.git.namcao@linutronix.de Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2026-07-24rv/rtapp/sleep: Stop monitoring kernel threadsNam Cao1-16/+6
The rtapp/sleep monitor's primary purpose is detecting common mistakes with user-space real-time design. Monitoring real-time issues with kernel threads is a bonus. However, accomodating kernel threads complicates the monitor due to the edge cases which is seen by the monitor as lower-priority task waking higher-priority task: - kthread_stop() wakes up the task in order to stop it. - The rcu thread and migration thread can be woken by any task. - The ktimerd thread is woken near the end of irq_exit_rcu(), where the preempt counter is "broken" and falsely says this is task context. This requires the monitor to use the hardirq_context flag instead of the preempt counter. Beside complicating the monitor, the final case also requires enabling CONFIG_TRACE_IRQFLAGS (so that "hardirq_context" can be used). This adds overhead to the kernel even when the monitor is not active. This may be an obstacle to enabling this monitor in distros' kernels. Furthermore, kernel threads usually are started before the monitor is enabled. Consequently, the threads' states (i.o.w. the monitor's atomic propositions for the threads) are not fully known to the monitor. As a result, the kernel threads mostly cannot be monitored. Overall, the downsides of accomodating kernel threads outweights the benefits. Thus, exclude kernel threads to simplify the monitor. Signed-off-by: Nam Cao <namcao@linutronix.de> Reviewed-by: Gabriele Monaco <gmonaco@redhat.com> Link: https://lore.kernel.org/r/eec2ca5224bcdacc45b8e1eb2f0e68109e1cae7a.1781852967.git.namcao@linutronix.de Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2026-07-24rv/rtapp/sleep: Update nanosleep ruleNam Cao1-7/+10
CLOCK_REALTIME is the only clock that often is misused in real-time applications. The other clocks either are safe for real-time uses (CLOCK_TAI, CLOCK_MONOTONIC, CLOCK_BOOTTIME) or are unlikely to be misused (CLOCK_AUX, CLOCK_PROCESS_CPUTIME_ID). Update the monitor to only warn about CLOCK_REALTIME. While at it, update the out-of-sync documentation. Signed-off-by: Nam Cao <namcao@linutronix.de> Reviewed-by: Gabriele Monaco <gmonaco@redhat.com> Link: https://lore.kernel.org/r/c7ceb5c6263ee8f43a2676acae669cf486b0d903.1781852967.git.namcao@linutronix.de Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2026-07-24rv/rtapp/sleep: Make the error more informative for userNam Cao1-1/+1
The rtapp/sleep monitor detects real-time tasks which go to sleep in an real-time-unsafe manner. If this happen, the monitor triggers a trace event in the sched_wakeup tracepoint's handler. However, the invoking context of that trace event is not the most informative, because of the stack trace of that event is the wakeup's code path which is not very helpful: 74.669317: rv:error_sleep: condvar[254]: violation detected ltl_validate+0x345 ([kernel.kallsyms]) handle_sched_wakeup+0x34 ([kernel.kallsyms]) ttwu_do_activate+0xff ([kernel.kallsyms]) sched_ttwu_pending+0x104 ([kernel.kallsyms]) __flush_smp_call_function_queue+0x15b ([kernel.kallsyms]) __sysvec_call_function_single+0x18 ([kernel.kallsyms]) sysvec_call_function_single+0x66 ([kernel.kallsyms]) asm_sysvec_call_function_single+0x1a ([kernel.kallsyms]) pv_native_safe_halt+0xf ([kernel.kallsyms]) default_idle+0x9 ([kernel.kallsyms]) default_idle_call+0x33 ([kernel.kallsyms]) do_idle+0x234 ([kernel.kallsyms]) cpu_startup_entry+0x24 ([kernel.kallsyms]) start_secondary+0xf8 ([kernel.kallsyms]) common_startup_64+0x13e ([kernel.kallsyms]) What would be much more valuable is the stack trace of the task itself. Instead of using the sched_wakeup tracepoint, use the sched_exit tracepoint. This makes the event happen in the task's context, making the stack trace far more informative for user: rv:error_sleep: condvar[254]: violation detected ltl_validate+0x345 ([kernel.kallsyms]) handle_sched_exit+0x39 ([kernel.kallsyms]) __schedule+0x80f ([kernel.kallsyms]) schedule+0x22 ([kernel.kallsyms]) futex_do_wait+0x33 ([kernel.kallsyms]) __futex_wait+0x8c ([kernel.kallsyms]) futex_wait+0x73 ([kernel.kallsyms]) do_futex+0xc6 ([kernel.kallsyms]) __x64_sys_futex+0x121 ([kernel.kallsyms]) do_syscall_64+0xf3 ([kernel.kallsyms]) entry_SYSCALL_64_after_hwframe+0x77 ([kernel.kallsyms]) __futex_abstimed_wait_common64+0xc6 (inlined) __futex_abstimed_wait_common+0xc6 (/usr/lib/x86_64-linux-gnu/libc.so.6) Signed-off-by: Nam Cao <namcao@linutronix.de> Reviewed-by: Gabriele Monaco <gmonaco@redhat.com> Link: https://lore.kernel.org/r/d97b4b5c476e5792b6875ec9bbf8dc214f999516.1781852967.git.namcao@linutronix.de Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2026-07-14tracing/probes: Add this_cpu_read() and this_cpu_ptr() dereference method to ↵Masami Hiramatsu (Google)2-0/+4
fetcharg When tracing the kernel local variables, sometimes we need to get the CPU local variables. To access it, current simple dereference is not enough. Thus, introduce a special this_cpu_read() dereference to access per-cpu variable for the current CPU (accessing other CPU variable may race with updates on other CPUs). Also this_cpu_ptr() is for accessing per-cpu pointer. Those are working as same as the kernel percpu macro. Link: https://lore.kernel.org/all/178271367680.1176915.4711734074448973989.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-14tracing/probes: Add $current variable supportMasami Hiramatsu (Google)2-0/+2
Since we can use the BTF to cast value to a structure pointer type, it is useful to introduce "$current" special variable support to fetcharg. User can define a fetcharg to access current task_struct properties using BTF info. e.g. $current->cpus_ptr Link: https://lore.kernel.org/all/178271366709.1176915.15320906169981578568.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-14tracing/probes: Support field specifier option for typecastMasami Hiramatsu (Google)3-7/+14
Add a field specifier option for the typecast. This works like container_of() macro. (STRUCT[,FIELD[.FIELD2...]])VAR This is equivalent to : container_of(VAR, struct STRUCT, FIELD[.FIELD2...]) For example: echo "f tick_nohz_handler next_tick=(tick_sched,sched_timer)timer->next_tick" >> dynamic_events This will trace tick_nohz_handler() with its tick_sched::next_tick which is converted from @timer by contianer_of(tick, struct tick_sched, sched_timer). So, if you enabkle both fprobes:tick_nohz_handler__entry and timer:hrtimer_expire_entry events, we will see something like: <idle>-0 [002] d.h1. 3778.087272: hrtimer_expire_entry: hrtimer=00000000d63db328 f unction=tick_nohz_handler now=3777450051040 <idle>-0 [002] d.h1. 3778.087281: tick_nohz_handler__entry: (tick_nohz_handler+0x4 /0x140) next_tick=3777450000000 Link: https://lore.kernel.org/all/178271365745.1176915.725923927180862257.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-14tracing/probes: Support nested typecastMasami Hiramatsu (Google)3-0/+6
When we hit an open parenthesis right after typecast closing parenthesis, it means we have nested typecast. This allows us to typecast a generic data member in a structure to a pointer to another structure. For example, to cast a DATA_MEMBER of VAR structure to STRUCT pointer and get MEMBER value. (STRUCT)(VAR->DATA_MEMBER)->MEMBER Also, we can nest typecast. (STRUCT1)((STRUCT2)$ARG->FIELD2)->FIELD1 Currently the max nest level is limited to 3. This also allows user to use typecasting for registers or stacks on kprobe events. e.g. (STRUCT)(%ax)->MEMBER (STRUCT)($stack0)->MEMBER Link: https://lore.kernel.org/all/178271363855.1176915.16793301788257446529.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-14tracing/probes: Support typecast for various probe eventsMasami Hiramatsu (Google)2-0/+7
Support BTF typecast feature on other probe events, but only if it is kernel function entry or return, and must use function parameter name or $retval. This means you can do: (STRUCT)PARAM->MEMBER Note: you can not use other variables like $stackN, %reg etc. That needs nesting support. To support other probe events, we just need to use last_struct type when we find a function parameter in parse_btf_arg(). This also updates <tracefs>/README file to show struct typecast. Link: https://lore.kernel.org/all/178271362928.1176915.12235759508786922490.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-06-25Merge tag 'docs-7.2-2' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux Pull more documentation updates from Jonathan Corbet: "A handful of late-arriving docs fixes, along with one document update that fell through the cracks before" * tag 'docs-7.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: docs: tools: Fix typo 'ackward' to 'awkward' in unittest.rst kdoc: xforms: ignore special static/inline macros kdoc: xforms_lists: handle DECLARE_PER_CPU() in kernel-doc MAINTAINERS: Fix regex for kdoc docs: kgdb: Fix path of driver options Documentation: tracing: fix typo in events documentation Docs/driver-api/uio-howto: document mmap_prepare callback docs/mm: clarify that we are not looking for LLM generated content kernel-doc: xforms: support __SYSFS_FUNCTION_ALTERNATIVE()
2026-06-23Documentation: tracing: fix typo in events documentationYudistira Putra1-1/+1
Fix a typo in the tracing events documentation: "can by built up" should be "can be built up". Signed-off-by: Yudistira Putra <pyudistira519@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260622143735.71778-1-pyudistira519@gmail.com>
2026-06-23Merge tag 'perf-tools-for-v7.2-1-2026-06-22' of ↵Linus Torvalds1-75/+3
git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools Pull perf tools updates from Arnaldo Carvalho de Melo: - Introduce 'perf inject --aslr' to remap ASLR-randomized addresses in perf.data files, enabling reproducible analysis across runs with different address space layouts - Refactor evsel out of sample processing paths: store evsel in struct perf_sample and remove the redundant evsel parameter from tool APIs, tracepoint handlers, hist entry iterators, and db-export, simplifying the entire tool callback chain - Switch architecture detection from string-based perf_env__arch() comparisons to the numeric ELF e_machine field across the codebase (capstone, print_insn, c2c, lock-contention, sort, sample-raw, machine, header), making cross-analysis more robust - Overhaul ARM CoreSight ETM tests: add deterministic and named_threads workloads, speed up basic and disassembly tests, add process attribution and concurrent threads tests, remove unused workloads and duplicate tests, queue context packets for the frontend decoder - Add ARM SPE IMPDEF event decoding for Arm Neoverse N1, store MIDR in arm_spe_pkt for per-CPU event mapping, handle missing CPU IDs gracefully - Refactor libunwind support: remove the libunwind-local backend, make register reading cross-platform, add RISC-V libunwind support, allow dynamic selection between libdw and libunwind unwinding at runtime - Extensive hardening of perf.data parsing against crafted files: add bounds checks and byte-swap validation for session records, feature sections, header attributes, BPF metadata, auxtrace errors, compressed events, CPU maps, build ID notes, and ELF program headers. Add minimum event size validation and file offset diagnostics - Fix libdw API contract violations across dwarf-aux, libdw, probe-finder, annotate-data, and debuginfo subsystems. Fix callchain parent update in ORDER_CALLER mode, support DWARF line 0 in inline lists, handle multiple address spaces in callchains - Fix numerous 'perf sched' bugs: thread reference leaks, memory leaks, heap overflows with cross-machine recordings, NULL dereferences, replace BUG_ON assertions with graceful error handling, bounds-check CPU indices, fix SIGCHLD vs pause() races in sched stats - Overhaul the build system: move BPF skeleton generation out of Makefile.perf into bpf_skel.mak, decouple pmu-events from the prepare target, make beauty generated C code standalone .o files, compile BPF skeletons with -mcpu=v3, fix continuous rebuilds, various cleanups - Add 'perf test' JUnit XML reporting with -j/--junit option, split monolithic test suites into sub-tests, add summary reporting, refactor parallel poll loop, fix test failures on musl-based systems - Fix 'perf c2c' memory leaks in hist entry and format list handling, use-after-free in error paths, bounds-check CPU and node IDs - Fix 'perf bpf' metadata leaks on duplicate insert and alloc failure, bounds-check array offsets, validate event sizes and func_info fields, add NULL checks - Fix hwmon PMU: off-by-one null termination on sysfs reads, strlcpy buffer overflow in parse_hwmon_filename(), fd 0 check, empty label reads, scnprintf usage - Fix symbols subsystem: bounds-check ELF and sysfs build ID note iteration, validate p_filesz, fix 32-bit ELF bswap error, fix signed overflow in size checks, bounds-check .gnu_debuglink section - Fix tools lib api: null termination in filename__read_int/ull(), uninitialized stack data in filename__write_int(), snprintf truncation in mount_overload() - Replace libbabeltrace with babeltrace2-ctf-writer for CTF conversion in 'perf data' - Add RISC-V SDT argument parsing for static tracepoints - Add 'perf trace --show-cpu' option to display CPU id - Add 'perf bench sched pipe --write-size' option - Add a perf-specific .clang-format that overrides some kernel style behaviors - Update Intel vendor events for Alder Lake, Arrow Lake, Clearwater Forest, Emerald Rapids, Granite Rapids, Grand Ridge, Lunar Lake, Meteor Lake, Panther Lake, Sapphire Rapids, Sierra Forest - Add IOMMU metrics for AMD and Intel - Fix AMD event: switch l2_itlb_misses to bp_l1_tlb_miss_l2_tlb_miss.all - Add AMD IBS improvements: decode Streaming-store and Remote-Socket flags, suppress bogus fields on Zen4+, skip privilege test on Zen6+ - Fix 'perf lock contention' SIGCHLD vs pause() race, allow 'mmap_lock' in -L filter, enable end-timestamp for cgroup aggregation, fix non-atomic data updates - Fix 'perf stat' false NMI watchdog warning in aggregation modes, bounds-check CPU index in topology callbacks, add aggr_nr metric parser support for uncore scaling - Fix 'perf timechart' memory leaks, CPU bounds checking, use-after-free on corrupted callchains - Fix 'perf inject' itrace branch stack synthesis, fix synthesized sample size with branch stacks - Fix DSO heap overflow on decompressed paths, uninitialized pathname on fallback, set proper error codes - Fix various snprintf/scnprintf usages to prevent buffer overflows and truncation across the codebase - Fix off-by-one stack buffer overflow in kallsyms__parse() - Fix 'perf kwork' memory management, address sanitizer issues, bounds check work->cpu - Fix 'perf tpebs' concurrent stop races and PID reuse hazards - Add O_CLOEXEC to open() calls and use mkostemp() for temporary files to prevent file descriptor leaks to child processes - Fix s390 Python extension TEXTREL by compiling as PIC - Fix build with ASAN for jitdump - Fix build failure due to btf_vlen() return type change * tag 'perf-tools-for-v7.2-1-2026-06-22' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (343 commits) perf bpf: Fix up build failure due to change of btf_vlen() return type perf dso: Set standard errno on decompression failure perf bpf: Validate array presence before casting BPF prog info pointers perf c2c: Fix hist entry and format list leaks in c2c_he_free() perf c2c: Free format list entries when c2c_hists__init() fails perf cs-etm: Bounds-check CPU in cs_etm__get_queue() perf cs-etm: Require full global header in auxtrace_info size check perf cs-etm: Validate num_cpu before metadata allocation perf machine: Use snprintf() for guestmount path construction perf machine: Propagate machine__init() error to callers perf trace: Guard __probe_ip suppression with evsel__is_probe() perf evsel: Add lazy-initialized probe type detection helpers perf evsel: Add no-libtraceevent stubs for evsel__field() and evsel__common_field() perf cs-etm: Reject CPU IDs that would overflow signed comparison perf c2c: Free format list entries when releasing c2c hist entries perf bpf: Bounds-check array offsets in bpil_offs_to_addr() perf bpf: Reject oversized BPF metadata events that truncate header.size perf bpf: Validate func_info_rec_size and sub_id in synthesize_bpf_prog_name() perf sched: Replace (void*)1 sentinel with proper runtime allocation perf hwmon: Fix fd check to accept fd 0 in hwmon_pmu__describe_items() ...
2026-06-16Merge tag 'probes-v7.2' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes updates from Masami Hiramatsu: - BTF support for dereferencing pointers Add syntax to the parsing of eprobes to typecast structure pointer trace event fields, enabling BTF-based dereferencing instead of relying on manual offsets. - Improvements and robustness enhancements - Use flexible array for entry fetch code. Store probe entry fetch instructions in the probe_entry_arg allocation via a flexible array member to simplify memory allocation and lifetime management. - Replace BUG_ON with lockdep_assert_held in uprobe_buffer functions Replace BUG_ON() calls with lockdep_assert_held() in uprobe buffer enable/disable paths to prevent kernel crashes and better verify lock ownership. - Ensure the uprobe buffer size is bigger than event size. Add a BUILD_BUG_ON() assertion to guarantee that the per-CPU uprobe working buffer size is always larger than the maximum probe event size. * tag 'probes-v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/eprobes: Allow use of BTF names to dereference pointers tracing: Replace BUG_ON with lockdep_assert_held in uprobe_buffer functions tracing: Use flexible array for entry fetch code tracing/probes: Ensure the uprobe buffer size is bigger than event size
2026-06-16Merge tag 'docs-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linuxLinus Torvalds2-3/+6
Pull documentation updates from Jonathan Corbet: "Things have calmed down a bit on the docs front, with no earthshaking changes this time around: - Ongoing work on the Japanese and Portuguese translations - Better integration of the MAINTAINERS file into the rendered documents, including a search interface - A seemingly infinite supply of fixes for typos, minor grammatical issues, and related problems that LLMs find with abandon" * tag 'docs-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (93 commits) docs: pt_BR: Translate 3.Early-stage.rst into Portuguese docs: pt_BR: update "Purpose of Defconfigs" section in maintainer-soc.rst Documentation: bug-hunting.rst: fix grammar docs/ja_JP: translate submitting-patches.rst (interleaved-replies) docs: Fix minor grammatical error docs/{it_it,sp_SP,zh_CN,zh_TW}: update references to removed CONFIG_DEBUG_SLAB Documentation: process: fix brackets Documentation: arch: fix brackets docs/dyndbg: explain flags parse 1st docs/dyndbg: update examples \012 to \n docs: kernel-parameters: Fix stale sticore file paths docs: real-time: Fix duplicated sched(7) text docs: kgdb: Fix stale source file paths docs: sonypi: Fix stale header file path docs: kernel-parameters: Remove sa1100ir IrDA parameter iommu: Documentation: rearrange, update kernel-parameters docs: md: fix grammar in speed_limit description docs: changes.rst: restore pahole 1.26 minimum (regressed by sort) Documentation: Fix syntax of kmalloc_objs example in coding style doc docs: pt_BR: update maintainer-handbooks ...
2026-06-16Merge tag 's390-7.2-1' of ↵Linus Torvalds1-0/+4
gitolite.kernel.org:pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Alexander Gordeev: - Use CIO device online variable instead of the internal FSM state to determine device availability during purge operations - Remove extra check of task_stack_page() because try_get_task_stack() already takes care of that when reading /proc/<pid>/wchan - Allow user-space to use the new SCLP action qualifier 4 for to provide NVMe SMART log data to the platform. - Send AP CHANGE uevents on successful bind and successful association to notify user-space about SE operations on AP queue devices - Add an s390dbf kernel parameter to configure debug log levels and area sizes during early boot - On arm64 the empty zero page is going to be mapped read-only. Do the same for s390 with an explicit set_memory_ro() call - Improve s390-specific bcr_serialize() and cpu_relax() implementations - Remove all unused variables to avoid allmodconfig W=1 build fails with latest clang-23 - Cleanup default Kconfig values for s390 selftests - Add a s390-tod trace clock to allow comparing trace timestamps between different systems or virtual machines on s390 - Remove the s390 implementation of strlcat() in favor of the generic variant - Make consistent the calling order between page_table_check_pte_clear() and secure page conversion across all code paths - Rearrange some fields within AP and zcrypt structs to reduce memory consumption and unused holes - Shorten GR_NUM and VX_NUM macros and move them to a separate header - Replace __get_free_page() with kmalloc() in few sources - Introduce an infrastructure for more efficient this_cpu operations. Eliminate conditional branches when PREEMPT_NONE is removed - Enable Rust support - Use z10 as minimum architecture level, similar to the boot code, to enforce a defined architecture level set - Improve and convert various mem*() helper functions to C. For that add .noinstr.text section to avoid orphaned warnings from the linker - Fix the function pointer type in __ret_from_fork() to correct the indirect call to match kernel thread return type of int - Revert support for DCACHE_WORD_ACCESS to avoid an endless exception loop on read from donated Ultravisor pages at unaligned addresses * tag 's390-7.2-1' of gitolite.kernel.org:pub/scm/linux/kernel/git/s390/linux: (52 commits) s390: Revert support for DCACHE_WORD_ACCESS s390/process: Fix kernel thread function pointer type s390/tishift: Convert __ashlti3(), __ashrti3(), __lshrti3() to C s390/memmove: Optimize backward copy case s390/string: Convert memset(16|32|64)() to C s390/string: Convert memcpy() to C s390/string: Convert memset() to C s390/string: Convert memmove() to C s390/string: Add -ffreestanding compile option to string.o s390: Add .noinstr.text to boot and purgatory linker scripts s390/purgatory: Enforce z10 minimum architecture level s390: Enable Rust support s390/cmpxchg: Fix KASAN stack-out-of-bounds in atomic helpers rust: helpers: Add memchr wrapper for string operations rust/bindgen_parameters: Mark s390 types as opaque to prevent repr conflicts s390/jump_label: Implement ARCH_STATIC_BRANCH_JUMP_ASM and ARCH_STATIC_BRANCH_ASM macros s390/bug: Provide ARCH_WARN_ASM for Rust WARN/BUG support s390/ap: Fix locking issue in SE bind and associate sysfs functions s390/percpu: Provide arch_this_cpu_write() implementation s390/percpu: Provide arch_this_cpu_read() implementation ...
2026-06-10perf test cs-etm: Remove unused Coresight workloadsJames Clark1-75/+3
These are now unused and had various issues like not working with out of source builds and being slow to compile. Delete them. Signed-off-by: James Clark <james.clark@linaro.org> Tested-by: Leo Yan <leo.yan@arm.com> Cc: Amir Ayupov <aaupov@meta.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Leach <mike.leach@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paschalis Mpeis <Paschalis.Mpeis@arm.com> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04buffer: Remove submit_bh()Matthew Wilcox (Oracle)1-2/+2
No users are left; remove this API. Also remove/fix comments mentioning it, and end_bio_bh_io_sync() as it's now unused. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://patch.msgid.link/20260528173150.1093780-32-willy@infradead.org Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
2026-06-02tracing/eprobes: Allow use of BTF names to dereference pointersSteven Rostedt1-0/+4
Add syntax to the parsing of eprobes to be able to typecast a trace event field that is a pointer to a structure. Currently, a dereference must be a nu