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10,428 commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo
1b4e9fbdea perf symbols: Bounds-check descsz in sysfs__read_build_id() GNU fallback
When sysfs__read_build_id() matches NT_GNU_BUILD_ID with the right
namesz but the name content is not "GNU", it falls back to reading
descsz bytes into the stack buffer bf[BUFSIZ]:

    } else if (read(fd, bf, descsz) != (ssize_t)descsz)

Unlike the else branch which validates namesz + descsz against
sizeof(bf), this path passes descsz directly to read() without any
bounds check.  A crafted sysfs file with a large n_descsz overflows
the 8192-byte stack buffer.

Add a descsz > sizeof(bf) check before the read, breaking out of
the loop on oversized values.

Fixes: e5a1845fc0 ("perf symbols: Split out util/symbol-elf.c")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
e1a2c9d70b perf hwmon: Fix parse_hwmon_filename() strlcpy buffer overflow
parse_hwmon_filename() strips the "_alarm" suffix from event names
by copying into a 24-byte stack buffer:

    strlcpy(fn_type, fn_item, fn_item_len - 5);

The third argument is the source length minus the suffix, not the
destination buffer capacity.  A long event name ending in "_alarm"
can have fn_item_len - 5 > sizeof(fn_type), causing strlcpy() to
write past the 24-byte fn_type[] array.  The assert() only validates
that the longest *valid* hwmon item fits, but does not protect
against crafted input.

Clamp the strlcpy size to min(fn_item_len - 5, sizeof(fn_type)).

Fixes: 4810b761f8 ("perf hwmon_pmu: Add hwmon filename parser")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
ae75956c16 perf hwmon: Use scnprintf() in hwmon_pmu__for_each_event()
hwmon_pmu__for_each_event() formats description strings via:

    len = snprintf(desc_buf, sizeof(desc_buf), "%s in unit %s named %s.", ...);
    len += hwmon_pmu__describe_items(hwm, desc_buf + len, sizeof(desc_buf) - len, ...);

If value->label is long enough to cause snprintf() to truncate, it
returns the would-have-been-written count, making len exceed
sizeof(desc_buf).  The subsequent sizeof(desc_buf) - len underflows
to a huge size_t value, disabling bounds checking in
hwmon_pmu__describe_items().

The alias_buf snprintf has the same issue.  Switch both to scnprintf()
which returns actual bytes written.

Fixes: 53cc0b351e ("perf hwmon_pmu: Add a tool PMU exposing events from hwmon in sysfs")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
1847c5fae3 perf hwmon: Fix off-by-one null termination on sysfs reads
Three functions read sysfs files into fixed-size stack buffers using
the full buffer size, then null-terminate at buf[read_len].  If the
read fills the buffer exactly, read_len equals sizeof(buf) and the
null byte writes one past the array, corrupting an adjacent stack
variable.

Fix all three by reading sizeof(buf) - 1 bytes, reserving space for
the null terminator:

  - hwmon_pmu__read_events(): buf[128]
  - hwmon_pmu__describe_items(): buf[64]
  - evsel__hwmon_pmu_read(): buf[32]

Fixes: 53cc0b351e ("perf hwmon_pmu: Add a tool PMU exposing events from hwmon in sysfs")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
31d5960545 perf tools: Fix thread__set_comm_from_proc() on empty comm file
thread__set_comm_from_proc() calls procfs__read_str() then strips
the trailing newline via comm[sz - 1] = '\0'.  procfs__read_str()
allocates the buffer before reading, so on an empty /proc/pid/comm
(reachable during late exit teardown) it returns success with sz = 0
and an unterminated heap buffer.

The sz - 1 underflow was the original sashiko finding: it writes a
null byte before the allocation.  But even with a sz > 0 guard on
the newline strip, the unterminated buffer would still be passed to
thread__set_comm() which calls strlen() — an unbounded heap read.

Fix by treating sz == 0 as failure: free the buffer and return -1.
This is consistent with pmu.c's perf_pmu__parse_scale/unit which
already treat len == 0 from filename__read_str as an error.

Fixes: 2f3027ac28 ("perf thread: Introduce method to set comm from /proc/pid/self")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
b6bb3b005d perf intel-pt: Fix snprintf size tracking bug in insn decoder
dump_insn() tracks remaining buffer space with a 'left' variable,
but the loop subtracts the cumulative offset 'n' each iteration
instead of just the per-iteration delta:

    n += snprintf(x->out + n, left, "%02x ", inbuf[i]);
    left -= n;  /* BUG: n is cumulative, not the delta */

After two iterations left goes massively negative, wrapping to a
huge value when passed as size_t to snprintf(), disabling all bounds
checking for the rest of the loop.

Switch to scnprintf() accumulation using sizeof(x->out) - n as the
remaining space, which is always correct and eliminates the separate
'left' variable entirely.

Fixes: 48d02a1d5c ("perf script: Add 'brstackinsn' for branch stacks")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
b8acc68f13 perf tools: Use mkostemp() for O_CLOEXEC on temporary files
mkstemp() creates file descriptors without the close-on-exec flag.
These fds leak to child processes spawned during symbol resolution
(addr2line, objdump), wasting descriptors and potentially exposing
temporary file contents.

Replace mkstemp() with mkostemp(tmpbuf, O_CLOEXEC) at all three
call sites:

  - filename__decompress() in dso.c
  - read_gnu_debugdata() in symbol-elf.c
  - kcore__init() in symbol-elf.c

Fixes: 42b3fa6708 ("perf tools: Introduce dso__decompress_kmodule_{fd,path}")
Fixes: b10f74308e ("perf symbol: Support .gnu_debugdata for symbols")
Fixes: afba19d9dc ("perf symbols: Workaround objdump difficulties with kcore")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
9c74f0aab3 perf symbols: Bounds-check .gnu_debuglink section data
filename__read_debuglink() copies .gnu_debuglink section data into a
caller-provided buffer via:

    strncpy(debuglink, data->d_buf, size);

where size is PATH_MAX.  If the ELF section is smaller than size and
lacks a null terminator, strncpy reads past data->d_buf into adjacent
memory.  A malformed ELF file can trigger this, potentially causing a
segfault or leaking heap data.

Additionally, strncpy does not guarantee null termination when the
source fills the buffer.

Replace with an explicit memcpy bounded by both the output buffer
size and the actual section data size (data->d_size), followed by
explicit null termination.

Fixes: e5a1845fc0 ("perf symbols: Split out util/symbol-elf.c")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
6eaa8ee3e2 perf symbols: Fix signed overflow in sysfs__read_build_id() size check
sysfs__read_build_id() reads ELF note headers from sysfs files.  The
note's namesz and descsz fields are used to compute the skip size:

    int n = namesz + descsz;
    if (n > (int)sizeof(bf))

Both namesz and descsz are size_t from NOTE_ALIGN() of 32-bit note
header fields.  Their sum can exceed INT_MAX, overflowing the signed
int n to a negative value.  The check n > sizeof(bf) then evaluates
false (negative < positive in signed comparison), and read(fd, bf, n)
reinterprets the negative n as a huge size_t count — the kernel writes
up to MAX_RW_COUNT bytes into the 8192-byte stack buffer.

In practice the overflow is bounded by the sysfs file's actual size,
so a real sysfs notes file won't trigger it organically.  But crafted
input (e.g. via a mounted debugfs/sysfs image) could.

Fix by validating namesz and descsz individually against the buffer
size before summing, and change n to size_t to avoid the signed
overflow entirely.

Fixes: f1617b4059 ("perf symbols: Record the build_ids of kernel modules too")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
33035f7dd4 perf pmu: Fix perf_pmu__parse_scale/unit() OOB access on empty sysfs file
perf_pmu__parse_scale() reads a PMU scale file then accesses
scale[sret - 1] to strip a trailing newline.  Only sret < 0 is
guarded, so an empty file (sret == 0) causes scale[-1] — a stack
buffer underflow that reads and potentially writes out of bounds.

perf_pmu__parse_unit() has the same pattern: alias->unit[sret - 1]
with sret == 0 accesses the byte before the struct member, which
may corrupt the adjacent pmu_name pointer field.

Change both guards from sret < 0 to sret <= 0 so that empty files
are treated as read errors.

Fixes: 410136f5dd ("tools/perf/stat: Add event unit and scale support")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Arnaldo Carvalho de Melo
836455e6db perf pmu: Fix pmu_id() heap underwrite on empty identifier file
pmu_id() calls filename__read_str() then strips the trailing newline
via str[len - 1] = 0.  If the PMU identifier file is empty,
filename__read_str() succeeds with len = 0.  len - 1 underflows
size_t to SIZE_MAX, writing a null byte before the heap allocation.

Add a len == 0 check before the newline stripping.

Fixes: 51d5484715 ("perf pmu: Add pmu_id()")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:56:01 -03:00
Namhyung Kim
2f4e244b59 perf jitdump: Fix a build error with ASAN
I found this error when I pass EXTRA_CFLAGS=-fsanitize=address on Fedora
44 with GCC 16.  Fix it by copying one less byte.

    CC      util/jitdump.o
  util/jitdump.c: In function ‘jit_process’:
  util/jitdump.c:237:9: error: ‘__builtin_strncpy’ specified bound 4096 equals destination size
                               [-Werror=stringop-truncation]
    237 |         strncpy(jd->dir, name, PATH_MAX);
        |         ^
  cc1: all warnings being treated as errors
  make[4]: *** [tools/build/Makefile.build:95: util/jitdump.o] Error 1
  make[4]: *** Waiting for unfinished jobs....
  make[3]: *** [tools/build/Makefile.build:158: util] Error 2
  make[2]: *** [Makefile.perf:578: perf-util-in.o] Error 2
  make[1]: *** [Makefile.perf:288: sub-make] Error 2
  make: *** [Makefile:76: all] Error 2

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:55:49 -03:00
James Clark
68ca50bc0f perf cs-etm: Queue context packets for frontend
PE_CONTEXT elements update the context ID and exception level, but the
decoder may still have prior packets cached for frontend processing.
Updating the context immediately in the decoder backend can make those
cached packets get consumed with the wrong thread or EL state.

Add a CS_ETM_CONTEXT packet carrying the TID and EL to the frontend,
this keeps context changes ordered with the rest of the packet stream
and avoids mismatches when synthesizing samples from cached packets.

Separate the memory access function into one for the frontend and one
for decoding. The frontend also needs memory access to attach the
instruction to samples. Because the frontend does memory access for
both previous and current packets, change all the frontend memory access
function signatures to take both a tidq and packet. But backend always
uses the current backend EL and thread from the tidq.

Treat context packets as a boundary for branch sample generation and
remove tidq->prev_packet_thread because it's not possible to branch to a
different thread, so only tracking the current thread is required for
sample generation.

Fixes: e573e978fb ("perf cs-etm: Inject capabilitity for CoreSight traces")
Reported-by: Amir Ayupov <aaupov@meta.com>
Closes: https://lore.kernel.org/linux-perf-users/20260515021135.1729028-1-aaupov@meta.com/
Co-authored-by: James Clark <james.clark@linaro.org>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Mike Leach <mike.leach@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paschalis Mpeis <Paschalis.Mpeis@arm.com>
Cc: Robert Walker <robert.walker@arm.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:55:48 -03:00
Athira Rajeev
4aa4d246c8 perf pmu: Use scnprintf in buffer offset calculations
Replace snprintf with scnprintf in buffer offset calculations to
ensure the 'used' count will not exceed the "len".

The current logic in perf_pmu__for_each_event uses an unconditional
+ 1 increment to buf_used to account for null terminators. This can
cause a stack buffer overflow in the subsequent scnprintf call.
When the local stack buffer buf (1024 bytes) is full, buf_used can
reach 1025. This causes the subsequent remaining space calculation
sizeof(buf) - buf_used to underflow.

Use sub_non_neg() to see if space actually existed, and only
increment the offset if remaining space is present.

Changes includes:
- Use sub_non_neg to check if space exists
- Replacing snprintf with scnprintf to ensure the return value
reflects the actual bytes written into the buffer.
- Only increment buf_used by 1 if space exists
- If a parameterized event uses a built-in perf keyword for its
parameter name (eg, config=?), the lexer parses it as a predefined
term token, which sets term->config to NULL. Add check to use
parse_events__term_type_str() if term->config is NULL.

Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Shivani Nittor <shivani@linux.ibm.com>
Cc: Tanushree.Shah@ibm.com
Cc: Tejas.Manhas1@ibm.com
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 18:55:29 -03:00
Athira Rajeev
4bd109899f perf tools: Fix the check for parameterized field in event term
The format_alias() function in util/pmu.c has a check to
detect whether the event has parameterized field ( =? ).
The string alias->terms contains the event and if the event
has user configurable parameter, there will be presence of
sub string "=?" in the alias->terms.

Snippet of code:

 /* Paramemterized events have the parameters shown. */
       if (strstr(alias->terms, "=?")) {
               /* No parameters. */
               snprintf(buf, len, "%.*s/%s/", (int)pmu_name_len, pmu->name, alias->name);

if "strstr" contains the substring, it returns a pointer
and hence enters the above check which is not the expected
check. And hence "perf list" doesn't have the parameterized
fields in the result.

Fix this check to use:

if (!strstr(alias->terms, "=?")) {

With this change, perf list shows the events correctly with
the strings showing parameters.

Before the fix:

 # ./perf list|grep -w PM_PAU_CYC
  hv_24x7/PM_PAU_CYC/                                [Kernel PMU event]

With this fix:

 # ./perf list|grep -w PM_PAU_CYC
  hv_24x7/PM_PAU_CYC,chip=?/                         [Kernel PMU event]

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com>
Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Shivani Nittor <shivani@linux.ibm.com>
Cc: Tanushree.Shah@ibm.com
Cc: Tejas.Manhas1@ibm.com
Cc: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 17:08:04 -03:00
Tanushree Shah
2857a5dca7 perf data convert json: Fix addr_location leak on time-filtered samples
When samples are skipped due to time filtering in process_sample_event(),
the early return path bypasses addr_location__exit(), causing memory leaks
of thread, map, and maps references acquired by machine__resolve().

These references must be released through addr_location__exit() before
returning.

Fixes: 8e746e95c3 ("perf data: Allow filtering conversion by time range")
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Tanushree Shah <tshah@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Derek Foreman <derek.foreman@collabora.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Shivani.Nittor@ibm.com
Cc: Tanushree.Shah@ibm.com
Cc: Tejas.Manhas1@ibm.com
Cc: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 17:05:48 -03:00
Jens Remus
bcd2cc4405 perf build: Do not duplicate CFLAGS in Python extension builds
setuptools already uses CFLAGS.  Passing CFLAGS with additional flags as
extra compile arguments causes CFLAGS to effectively get passed twice:

$ make -C tools/perf V=1 JOBS=1
...
building 'perf' extension
gcc [CFLAGS] -fPIC -Iutil/include -I/usr/include/python3.14 \
  -c /root/linux/tools/perf/util/python.c \
  -o python_ext_build/tmp/root/linux/tools/perf/util/python.o \
  [CFLAGS] \
  -fno-strict-aliasing -Wno-write-strings -Wno-unused-parameter \
  -Wno-redundant-decls -Wno-cast-function-type \
  -Wno-declaration-after-statement

Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 17:00:40 -03:00
Arnaldo Carvalho de Melo
e33711d5e7 perf tools: Use scnprintf() in build_id__snprintf() and hwmon read_events()
build_id__snprintf() and hwmon_pmu__read_events() accumulate formatted
output via snprintf(), which returns the would-have-been-written count
on truncation.  In build_id__snprintf(), this inflates the return
value beyond the buffer size.  In hwmon_pmu__read_events(), len
overshoots out_buf_len and the next 'out_buf_len - len' underflows.

Switch both to scnprintf() which returns actual bytes written.

In build_id__snprintf(), also tighten the loop guard from
'offs < bf_size' to 'offs + 1 < bf_size': since scnprintf() returns
at most size-1, offs never reaches bf_size, and the original condition
would spin doing zero-byte writes once the buffer fills.

Fixes: fccaaf6fbb ("perf build-id: Change sprintf functions to snprintf")
Fixes: 53cc0b351e ("perf hwmon_pmu: Add a tool PMU exposing events from hwmon in sysfs")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 15:23:53 -03:00
Arnaldo Carvalho de Melo
227a874874 perf hists: Fix snprintf() in hists__scnprintf_title() UID filter path
hists__scnprintf_title() accumulates formatted output into a buffer
using scnprintf() for all filter clauses except the UID filter, which
uses snprintf().  If the buffer fills up and snprintf() returns more
than the remaining space, printed exceeds size and the next 'size -
printed' underflows, causing later scnprintf() calls to write past
the buffer.

Switch the UID filter clause to scnprintf() to match the rest of the
function.

Fixes: 25c312dbf8 ("perf hists: Move hists__scnprintf_title() away from the TUI code")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 15:23:53 -03:00
Arnaldo Carvalho de Melo
cab3a9331e perf bpf: Use scnprintf() in snprintf_hex() and synthesize_bpf_prog_name()
Both functions accumulate formatted output via ret += snprintf(buf + ret,
size - ret, ...).  If the buffer is too small and snprintf() returns more
than the remaining space, ret exceeds size and the next 'size - ret'
underflows, causing snprintf() to write past the buffer end.

Switch to scnprintf() which returns the actual number of bytes written,
making the accumulation safe.

Fixes: 7b612e291a ("perf tools: Synthesize PERF_RECORD_* for loaded BPF programs")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Song Liu <song@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 15:23:53 -03:00
Arnaldo Carvalho de Melo
b145137fec perf tools: Add O_CLOEXEC to open() calls in DSO and ELF code
open() calls in dso.c and symbol-elf.c omit O_CLOEXEC, which leaks
file descriptors to child processes spawned during symbol resolution
(e.g., addr2line, objdump).  This can exhaust the fd limit during
long profiling sessions or when processing many DSOs.

Add O_CLOEXEC to all open() calls in both files (12 call sites).

Fixes: cdd059d731 ("perf tools: Move dso_* related functions into dso object")
Fixes: e5a1845fc0 ("perf symbols: Split out util/symbol-elf.c")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 15:23:53 -03:00
Arnaldo Carvalho de Melo
a9e900bc5c perf tools: NULL bitmap pointers after bitmap_free()
Two call sites free bitmaps without NULLing the pointer, risking
double-free if the structure is reused or cleanup is called twice:

 - mmap__munmap():                 map->affinity_mask.bits
 - record__mmap_cpu_mask_free():   mask->bits

Set each pointer to NULL after bitmap_free().

Fixes: 8384a2600c ("perf record: Adapt affinity to machines with #CPUs > 1K")
Fixes: f466e5ed6c ("perf record: Extend --threads command line option")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 13:13:32 -03:00
Arnaldo Carvalho de Melo
5484b43a0e perf tools: Use perf_env__get_cpu_topology() in machine__resolve()
machine__resolve() accesses env->cpu[al->cpu].socket_id after checking
al->cpu >= 0 and env->cpu != NULL, but without validating al->cpu
against env->nr_cpus_avail.  Since al->cpu comes from the untrusted
perf.data sample, a crafted file with a large CPU index causes an
out-of-bounds heap read.

Use perf_env__get_cpu_topology() which validates both NULL and bounds.
Also bounds-check al->cpu before the cast to struct perf_cpu (int16_t):
without this, values like 65536 silently truncate to 0, bypassing the
accessor's internal check and returning CPU 0's topology.

Fixes: 0c4c4debb0 ("perf tools: Add processor socket info to hist_entry and addr_location")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 11:38:45 -03:00
Arnaldo Carvalho de Melo
7953a3a9b8 perf tools: Use scnprintf() in cpu_map__snprint() to prevent overflow
cpu_map__snprint() accumulates snprintf() return values in ret.
snprintf() returns the number of characters that *would have been
written* on truncation, not the actual count.  When a fragmented CPU
list exceeds the buffer, ret grows past size, causing `size - ret` to
underflow (both are size_t), and subsequent snprintf() calls write
past the end of the caller's stack buffer.

Switch to scnprintf() which returns the actual number of characters
written, making ret accumulation safe by construction.

Fixes: a24020e6b7 ("perf tools: Change cpu_map__fprintf output")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 11:38:45 -03:00
Arnaldo Carvalho de Melo
0a012113bb perf tools: Fix get_max_num() size_t underflow on empty sysfs file
get_max_num() reads a sysfs file (cpu/possible, cpu/present, or
node/possible) and scans backward from the end to find the last
number.  If the file is empty, filename__read_str() returns num == 0.
The loop `while (--num)` decrements the size_t from 0 to SIZE_MAX,
reading backward across the heap until a comma or hyphen is found
or unmapped memory is hit.

Add an early return for empty files before the backward scan.

Fixes: 7780c25bae ("perf tools: Allow ability to map cpus to nodes easily")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-10 11:38:45 -03:00
Arnaldo Carvalho de Melo
c3e51ed45f perf sched: Free callchain nodes in idle thread cleanup
free_idle_threads() relies on the thread priv destructor (free()) to
clean up idle_thread_runtime structs.  But free() doesn't walk the
callchain_cursor linked list or the callchain_root tree allocated
by callchain_cursor__copy() and callchain_append() during --idle-hist
processing.  Every idle thread with callchain data leaks these nodes.

Introduce callchain_cursor_cleanup() to free the cursor's linked list
of callchain_cursor_node entries, and call it together with
free_callchain() in free_idle_threads() before thread__put().

Fixes: 225b24f569980ac9 ("perf sched timehist: Save callchain when entering idle")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-06 14:42:19 -03:00
Arnaldo Carvalho de Melo
33fa2bf560 perf tools: Fix int16_t truncation of max_cpu_num in set_max_cpu_num()
set_max_cpu_num() assigns the sysfs "possible" CPU count to
max_cpu_num.cpu which is int16_t (struct perf_cpu).  On systems
with >32767 possible CPUs the value silently truncates, potentially
wrapping negative.  This causes cpunode_map to be underallocated
and subsequent cpu__get_node() calls to read out of bounds.

The matching check for max_present_cpu_num was added by commit
c760174401 ("perf cpumap: Reduce cpu size from int to int16_t")
but max_cpu_num was missed.  Add the same INT16_MAX guard.

Fixes: c760174401 ("perf cpumap: Reduce cpu size from int to int16_t")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-06 14:42:19 -03:00
Arnaldo Carvalho de Melo
e2496db45b perf timechart: Fix cpu2y() OOB read on untrusted CPU index
cpu2y() indexes topology_map[cpu] without bounds checking.  The array
is allocated with nr_cpus entries (from env->nr_cpus_online), but
callers pass sample CPU values from perf.data which can exceed that
size with cross-machine recordings.

Track the topology_map allocation size and bounds-check the CPU
argument in cpu2y() before indexing.  Out-of-bounds CPUs fall back
to the identity mapping (cpu2slot(cpu)), which is the same behavior
as when no topology is available.

Fixes: c507999790 ("perf timechart: Add support for topology")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Stanislav Fomichev <stfomichev@yandex-team.ru>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-06 14:27:52 -03:00
Arnaldo Carvalho de Melo
afa4363a91 perf stat: Introduce perf_env__get_cpu_topology() to guard NULL env->cpu
process_cpu_topology() in header.c frees env->cpu on old-format
perf.data files that predate topology information, but leaves
nr_cpus_avail set.  The six perf_env__get_*_aggr_by_cpu() functions
in builtin-stat.c pass the bounds check but dereference a NULL
env->cpu pointer, crashing on old recordings.

Introduce perf_env__get_cpu_topology() as a safe accessor that
validates env->cpu, cpu.cpu >= 0, and cpu.cpu < nr_cpus_avail in
one place, returning a struct cpu_topology_map pointer or NULL.
Convert all six topology aggregation callbacks to use it.

Fixes: 88031a0de7 ("perf stat: Switch to cpu version of cpu_map__get()")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-06 13:44:46 -03:00
Arnaldo Carvalho de Melo
25627346b1 perf mmap: Fix NULL deref in aio cleanup on alloc failure
perf_mmap__aio_mmap() sets map->aio.nr_cblocks before allocating the
data array.  If calloc() for aiocb or cblocks fails before the data
array is allocated, the return -1 path leads to perf_mmap__aio_munmap()
which loops nr_cblocks times calling perf_mmap__aio_free().  Both
versions of perf_mmap__aio_free() (NUMA and non-NUMA) dereference
map->aio.data[idx] without checking if data is NULL, causing a NULL
pointer dereference.

Add NULL checks for map->aio.data at the top of both
perf_mmap__aio_free() variants so the cleanup path is safe when
allocation fails partway through perf_mmap__aio_mmap().

Fixes: d3d1af6f01 ("perf record: Enable asynchronous trace writing")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-06 11:03:29 -03:00
Arnaldo Carvalho de Melo
f32dc302a0 perf mmap: Guard cpu__get_node() return in aio_bind()
perf_mmap__aio_bind() passes the cpu__get_node() return value directly
to an unsigned long variable (node_index).  When cpu__get_node() returns
-1 for an unknown CPU, the implicit int-to-unsigned-long conversion
sign-extends it to ULONG_MAX.

This causes bitmap_zalloc(ULONG_MAX + 1) which wraps to
bitmap_zalloc(0), returning a zero-sized allocation.  The subsequent
__set_bit(ULONG_MAX, node_mask) then writes massively out of bounds.

Check the return value in a signed temporary before assigning to
node_index, and skip the NUMA binding when the node is unknown.

Fixes: c44a8b44ca ("perf record: Bind the AIO user space buffers to nodes")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-05 17:22:21 -03:00
Arnaldo Carvalho de Melo
1e7921d722 perf tools: Add bounds check to cpu__get_node()
cpu__get_node() accesses cpunode_map[cpu.cpu] without checking against
max_cpu_num, the allocation size of cpunode_map.  Callers such as
builtin-kmem.c:evsel__process_alloc_event() pass sample->cpu from
perf.data events, which may exceed the host's CPU count when analyzing
cross-machine recordings.

Add a bounds check against max_cpu_num before indexing, returning -1
for out-of-range values.  This is a central fix that protects all
callers.

Fixes: 86895b480a ("perf stat: Add --per-node agregation support")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 19:17:36 -03:00
Arnaldo Carvalho de Melo
7ccd2e6cec perf tools: Guard remaining test_bit calls from OOB sample CPU
auxtrace.c:filter_cpu() and builtin-script.c:filter_cpu() call
test_bit(cpu, cpu_bitmap) where cpu_bitmap is declared with
MAX_NR_CPUS bits.  When the CPU value from a perf.data event is
corrupt or absent (e.g. negative or >= MAX_NR_CPUS), test_bit reads
out of bounds.

Add bounds checks before test_bit(): >= 0 for the int16_t cpu.cpu in
auxtrace (which also covers the -1 sentinel), and < MAX_NR_CPUS for
both sites.  Matches the pattern applied in the previous series for
builtin-annotate.c, builtin-diff.c, builtin-report.c, and
builtin-sched.c.

Fixes: 644e0840ad ("perf auxtrace: Add CPU filter support")
Fixes: 5d67be97f8 ("perf report/annotate/script: Add option to specify a CPU range")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 19:17:36 -03:00
Suchit Karunakaran
824b18f607 perf lock contention: Enable end-timestamp accounting for cgroup aggregation
update_lock_stat() handles lock contentions that start but never reach a
contention_end event (e.g., locks still held when profiling stops), but
previously treated LOCK_AGGR_CGROUP as a no-op due to missing cgroup
context in userspace.

Fix this by adding a cgroup_id field to struct tstamp_data, recording it
at contention_begin using get_current_cgroup_id() when aggr_mode is
LOCK_AGGR_CGROUP. Capturing it at contention_begin is semantically
correct, the contention cost is incurred by the task that had to wait,
not by whatever task happens to be running at contention_end. It is also
preferable from a performance standpoint, as contention_end runs just
before the task enters the critical section.

Update contention_end to use pelem->cgroup_id instead of calling
get_current_cgroup_id() dynamically, ensuring both complete and
incomplete contention events attribute the wait time to the cgroup at
wait-start time consistently.

Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Suchit Karunakaran <suchitkarunakaran@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tycho Andersen (AMD) <tycho@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 17:34:52 -03:00
Ian Rogers
be694c488a perf pmu: Recognize 'default_core' as a core PMU and document matching
The is_pmu_core function checks if a PMU name corresponds to a core
CPU PMU. However, it currently fails to recognize "default_core" as
a core PMU.

When "default_core" is used, the PMU scanning fallback in pmus.c
scans the "other_pmus" list. This scan is slow and always misses because
"default_core" is a core PMU, leading to unnecessary overhead.

Update is_pmu_core to recognize "default_core" directly. Additionally,
document the different matching approaches (exact name for x86/s390,
sysfs-based cpus file check for ARM/hybrid) to clarify how core PMUs are
classified.

Also, explicitly treat "default_core" as `all_pmus` in `setup_metric_events()`
to preserve the original metric resolution behavior for this pseudo-PMU.

Assisted-by: Gemini-CLI:Google Gemini 3.1 Pro
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 17:34:52 -03:00
Michael Jeanson
536e81f074 perf data ctf: replace libbabeltrace with babeltrace2-ctf-writer
The 1.x branch of Babeltrace has been superseded by 2.x in 2020 and has
been unmaintained since 2022, efforts have started to remove it from
popular distributions.

Babeltrace 2.x offers a very similar 'ctf-writer' library that can be used
with minimal changes for the '--to-ctf' feature and has been packaged
since Debian 11 and Fedora 32.

This patch replaces the 'libbabeltrace' build feature with
'babeltrace2-ctf-writer' using pkgconfig detection, adjusts the naming of
the public headers and applies minor API cleanups.

There is no changes to the output ctf traces, the ctf-writer API still
implements version 1.8 of the CTF specification that can be read by
either Babeltrace 1 / 2 or any CTF compliant reader.

Also remove some ifdefs in the cli option parsing to allow printing the
helpful error message with '--to-ctf' when built without babeltrace2.

Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Derek Foreman <derek.foreman@collabora.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 17:34:52 -03:00
Namhyung Kim
b72ab69175 perf lock contention: Allow 'mmap_lock' in -L/--lock-filter
The -L/--lock-filter option is to specify target locks by name or
address.  It's basically for global locks where name or address is known
and fixed.  But 'mmap_lock' is a per-process lock so it cannot be used
for the -L option.

  $ sudo perf lock con -ab -L mmap_lock
  ignore unknown symbol: mmap_lock
  libbpf: map 'addr_filter': failed to create: -EINVAL
  libbpf: failed to load BPF skeleton 'lock_contention_bpf': -EINVAL
  Failed to load lock-contention BPF skeleton
  lock contention BPF setup failed

However, it's still a common source of contention especially in a large
process so we want to use it for the -L/--lock-filter option.  As there
is check_lock_type() to check mmap_lock at runtime, let's used it to
filter mmap_locks as a special case.

Of course, this only works with -b/--use-bpf option.

  $ sudo perf lock con -b -L mmap_lock -- perf bench mem mmap -f demand -t 2
  # Running 'mem/mmap' benchmark:
  # function 'demand' (Demand loaded mmap())
  # Copying 1MB bytes ...

         2.679184 GB/sec/thread	( +-   1.78% )
   contended   total wait     max wait     avg wait         type   caller

           1     15.22 us     15.22 us     15.22 us      rwsem:W   __vm_munmap+0x7e
           1      7.72 us      7.72 us      7.72 us      rwsem:R   lock_mm_and_find_vma+0x97

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suchit Karunakaran <suchitkarunakaran@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 17:34:52 -03:00
Ian Rogers
a77ecea7ce perf test: Remove /usr/bin/cc dependency from Intel PT shell test
In test_intel_pt.sh, the test script compiled two external C programs at
runtime using /usr/bin/cc (a thread loop workload and a JIT self-
modifying workload). Relying on external C compilers inside shell tests
frequently causes failures in continuous integration environments.

Create a built-in 'jitdump' workload and switch test_intel_pt.sh to use
'perf test -w thloop' and 'perf test -w jitdump'. Also add multi-
architecture compatibility without external C compiler dependencies, the
workload instruction arrays dynamically encode CHK_BYTE into opcodes
across x86, ARM32, ARM64, RISC-V, PowerPC, MIPS, LoongArch, and s390x.

Some minor include fixes for util/jitdump.h.

Assisted-by: Gemini-CLI:Google Gemini 3
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 11:41:46 -03:00
Ian Rogers
bded0398ac perf tpebs: Fix concurrent stop races and PID reuse hazards in tpebs_stop
Parallel verbose test execution can trigger a race condition in tpebs_stop
if called concurrently or when PID reuse occurs, causing finish_command()
to block or reap the wrong process.

Introduce a `tpebs_stopping` flag inside intel-tpebs.c to prevent
redundant stop execution paths, and safely restore the `cmd.pid`
temporarily only during `finish_command()` to ensure it is properly reaped,
while preventing other threads from referencing it.

Assisted-by: Gemini-CLI:Google Gemini 3
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 11:35:04 -03:00
Ian Rogers
154b7c3ec4 perf tools: Ensure event leader stays at head of evlist after sorting
For evlist of a certain event/metric, the HEAD should be the event
leader. In some scenarios where uncore_xxx_0 does not exist, the event
leader is not the first element after sorting. For example, on my test
machine uncore_iio_0 does not exist, the event leader is uncore_iio_2.

However, in `evlist__cmp`, it was reordered based on the PMU name, which
makes uncore_iio_1 the HEAD of evlist, breaking the following merge
logic in `evsel__merge_aliases`.

The patch adds a loop at the end of
`parse_events__sort_events_and_fix_groups` to make sure the first
wildcard match is the earliest entry in the list, updating pointers
accordingly without breaking reordering detection.

Tested on device lacks uncore_iio_0, and `perf test` looks good.

Signed-off-by: Chun-Tse Shao <ctshao@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 11:03:52 -03:00
Chun-Tse Shao
e565ceb48b perf stat: Add aggr_nr metric parser support
Introduce the `aggr_nr` function to the metric expression parser.
`aggr_nr` allows metric formulas to dynamically utilize the number of
aggregated targets (`aggr->nr`) instead of relying on the static
`source_count` (which represents the static socket or node count).

This adds the `AGGR_NR` token to the lexer and parser, updates the
expression parsing context helpers to store `aggr_nr`, and feeds
`aggr->nr` from the aggregation structure in `prepare_metric`.

Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Chun-Tse Shao <ctshao@google.com>
Tested-by: Zide Chen <zide.chen@intel.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 10:58:47 -03:00
Suchit Karunakaran
7a92b1e22d perf lock: Fix non-atomic max/time and min_time updates in contention_data
The update_contention_data() had a FIXME noting that max_time and
min_time updates lacked atomicity. Two CPUs could simultaneously read a
stale value, pass the comparison check and race on the write-back, with
the smaller value potentially overwriting the larger one and silently
corrupting the statistics.

Fix this by replacing the bare conditional assignments with a
bpf_loop()-based CAS retry loop. Each field tracks its own convergence
independently via max_done/min_done flags in cas_ctx, so a successful
CAS on one field is never retried even if the other field needs more
attempts.

Signed-off-by: Suchit Karunakaran <suchitkarunakaran@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04 10:33:06 -03:00
Ian Rogers
044462f6f6 perf symbol: Lazily compute idle
Switch from an idle boolean to a helper symbol__is_idle function. In
the function lazily compute whether a symbol is an idle function
taking into consideration the kernel version and architecture of the
machine. As symbols__insert no longer needs to know if a symbol is for
the kernel, remove the argument.

To protect against drop-filtering of legitimate setup, online, or hotplug
management functions (such as intel_idle_init), x86 matches are strictly
constrained to exact known run-loops (intel_idle, intel_idle_irq,
mwait_idle, mwait_idle_with_hints).

If the target environment OS release is unresolvable (such as on guest
traces), default to treating psw_idle as idle to prevent false
negatives and match legacy trace behavior safely.

This change is inspired by mailing list discussion, particularly from
Thomas Richter <tmricht@linux.ibm.com> and Heiko Carstens
<hca@linux.ibm.com>:
https://lore.kernel.org/lkml/20260219113850.354271-1-tmricht@linux.ibm.com/

Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Honglei Wang <jameshongleiwang@126.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-03 16:54:09 -03:00
Ian Rogers
979e87ab1f perf symbol: Add setters for bitfields sharing a byte to avoid concurrent update issues
A problem with putting bitfields into struct symbol is that other bits in
the symbol could be updated concurrently and only one update to the
underlying storage unit happen, leading to lost updates.

To avoid this, use atomics to atomically read or set part of 16-bits
of flags in the symbol. Add accessors to simplify this.

The idle value has 3 values in preparation for a later change that
will lazily update it.

Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Honglei Wang <jameshongleiwang@126.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-03 16:53:45 -03:00
Ian Rogers
b34c7c147b perf env: Add helper to lazily compute the os_release
In live mode the os_release isn't being initialized, make a lazy
initialization helper that assumes when the os_release isn't
initialized this is live mode.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Honglei Wang <jameshongleiwang@126.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-03 16:53:16 -03:00
Ian Rogers
0ff9718c26 perf env: Add mutex to protect lazy environment initialization
Introduce a mutex to 'struct perf_env' to safely protect lazy
metadata setup, such as os_release or e_machine resolution,
preventing concurrent initialization data races and memory leaks
during multi-threaded profiling or symbol loading.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Honglei Wang <jameshongleiwang@126.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-03 16:52:49 -03:00
Ian Rogers
da976dd484 perf env: Remove unused perf_env__raw_arch
The switch to using e_machine has made the perf_env__raw_arch function
unused so remove it.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Honglei Wang <jameshongleiwang@126.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-03 16:52:27 -03:00
Ian Rogers
13d5660026 perf env: Refactor perf_env__arch_strerrno
The previous approach maps an architecture string to a function
pointer to a function that takes an int errno value and returns a
string. The new approach takes an e_machine and an errno value and
returns a string.

As the only call site is in builtin-trace.c, the e_machine is already
present and potentially more specific than the perf_env arch string
that is a single global value.

Since the errno-to-name mapping is now generated statically and no
longer depends on libtraceevent, we can remove the HAVE_LIBTRACEEVENT
guards entirely, making perf_env__arch_strerrno unconditionally
available.

The major complication in this approach is having the shell script
that generates the C code map a linux directory name to the matching
ELF machine constants. To ensure compatibility with older hosts that
have older glibc versions, output fallback definitions for newer ELF
machine constants (EM_AARCH64, EM_CSKY, EM_LOONGARCH) if they are not
defined in the system <elf.h>.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Honglei Wang <jameshongleiwang@126.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-03 16:50:45 -03:00
Ian Rogers
661b1d83ef perf lock-contention: Use perf_env e_machine rather than arch
Use the e_machine rather than arch string matching for powerpc.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Honglei Wang <jameshongleiwang@126.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-03 16:50:34 -03:00
Ian Rogers
5d57371b9c perf header: In print_pmu_caps use perf_env e_machine
Switch from arch to e_machine in print_pmu_caps.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Honglei Wang <jameshongleiwang@126.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-03 16:49:56 -03:00