linux-stable.git/tools, branch v5.4.292

perf python: Check if there is space to copy all the event

2025-04-10T12:29:42+00:00

[ Upstream commit 89aaeaf84231157288035b366cb6300c1c6cac64 ]

The pyrf_event__new() method copies the event obtained from the perf
ring buffer to a structure that will then be turned into a python object
for further consumption, so it copies perf_event.header.size bytes to
its 'event' member:

  $ pahole -C pyrf_event /tmp/build/perf-tools-next/python/perf.cpython-312-x86_64-linux-gnu.so
  struct pyrf_event {
  	PyObject                   ob_base;              /*     0    16 */
  	struct evsel *             evsel;                /*    16     8 */
  	struct perf_sample         sample;               /*    24   312 */

  	/* XXX last struct has 7 bytes of padding, 2 holes */

  	/* --- cacheline 5 boundary (320 bytes) was 16 bytes ago --- */
  	union perf_event           event;                /*   336  4168 */

  	/* size: 4504, cachelines: 71, members: 4 */
  	/* member types with holes: 1, total: 2 */
  	/* paddings: 1, sum paddings: 7 */
  	/* last cacheline: 24 bytes */
  };

  $

It was doing so without checking if the event just obtained has more
than that space, fix it.

This isn't a proper, final solution, as we need to support larger
events, but for the time being we at least bounds check and document it.

Fixes: 877108e42b1b9ba6 ("perf tools: Initial python binding")
Signed-off-by: Arnaldo Carvalho de Melo 
Reviewed-by: Ian Rogers 
Link: https://lore.kernel.org/r/20250312203141.285263-7-acme@kernel.org
Signed-off-by: Namhyung Kim 
Signed-off-by: Sasha Levin

perf python: Decrement the refcount of just created event on failure

2025-04-10T12:29:41+00:00

[ Upstream commit 3de5a2bf5b4847f7a59a184568f969f8fe05d57f ]

To avoid a leak if we have the python object but then something happens
and we need to return the operation, decrement the offset of the newly
created object.

Fixes: 377f698db12150a1 ("perf python: Add struct evsel into struct pyrf_event")
Signed-off-by: Arnaldo Carvalho de Melo 
Reviewed-by: Ian Rogers 
Link: https://lore.kernel.org/r/20250312203141.285263-5-acme@kernel.org
Signed-off-by: Namhyung Kim 
Signed-off-by: Sasha Levin

perf python: Fixup description of sample.id event member

2025-04-10T12:29:41+00:00

[ Upstream commit 1376c195e8ad327bb9f2d32e0acc5ac39e7cb30a ]

Some old cut'n'paste error, its "ip", so the description should be
"event ip", not "event type".

Fixes: 877108e42b1b9ba6 ("perf tools: Initial python binding")
Signed-off-by: Arnaldo Carvalho de Melo 
Reviewed-by: Ian Rogers 
Link: https://lore.kernel.org/r/20250312203141.285263-2-acme@kernel.org
Signed-off-by: Namhyung Kim 
Signed-off-by: Sasha Levin

perf units: Fix insufficient array space

2025-04-10T12:29:41+00:00

[ Upstream commit cf67629f7f637fb988228abdb3aae46d0c1748fe ]

No need to specify the array size, let the compiler figure that out.

This addresses this compiler warning that was noticed while build
testing on fedora rawhide:

  31    15.81 fedora:rawhide                : FAIL gcc version 15.0.1 20250225 (Red Hat 15.0.1-0) (GCC)
    util/units.c: In function 'unit_number__scnprintf':
    util/units.c:67:24: error: initializer-string for array of 'char' is too long [-Werror=unterminated-string-initialization]
       67 |         char unit[4] = "BKMG";
          |                        ^~~~~~
    cc1: all warnings being treated as errors

Fixes: 9808143ba2e54818 ("perf tools: Add unit_number__scnprintf function")
Signed-off-by: Arnaldo Carvalho de Melo 
Link: https://lore.kernel.org/r/20250310194534.265487-3-acme@kernel.org
Signed-off-by: Namhyung Kim 
Signed-off-by: Sasha Levin

perf bench: Fix undefined behavior in cmpworker()

2025-03-13T11:43:08+00:00

commit 62892e77b8a64b9dc0e1da75980aa145347b6820 upstream.

The comparison function cmpworker() violates the C standard's
requirements for qsort() comparison functions, which mandate symmetry
and transitivity:

Symmetry: If x < y, then y > x.
Transitivity: If x < y and y < z, then x < z.

In its current implementation, cmpworker() incorrectly returns 0 when
w1->tid < w2->tid, which breaks both symmetry and transitivity. This
violation causes undefined behavior, potentially leading to issues such
as memory corruption in glibc [1].

Fix the issue by returning -1 when w1->tid < w2->tid, ensuring
compliance with the C standard and preventing undefined behavior.

Link: https://www.qualys.com/2024/01/30/qsort.txt [1]
Fixes: 121dd9ea0116 ("perf bench: Add epoll parallel epoll_wait benchmark")
Cc: stable@vger.kernel.org
Signed-off-by: Kuan-Wei Chiu 
Reviewed-by: James Clark 
Link: https://lore.kernel.org/r/20250116110842.4087530-1-visitorckw@gmail.com
Signed-off-by: Namhyung Kim 
Signed-off-by: Greg Kroah-Hartman

udp: gso: do not drop small packets when PMTU reduces

2025-03-13T11:43:06+00:00

[ Upstream commit 235174b2bed88501fda689c113c55737f99332d8 ]

Commit 4094871db1d6 ("udp: only do GSO if # of segs > 1") avoided GSO
for small packets. But the kernel currently dismisses GSO requests only
after checking MTU/PMTU on gso_size. This means any packets, regardless
of their payload sizes, could be dropped when PMTU becomes smaller than
requested gso_size. We encountered this issue in production and it
caused a reliability problem that new QUIC connection cannot be
established before PMTU cache expired, while non GSO sockets still
worked fine at the same time.

Ideally, do not check any GSO related constraints when payload size is
smaller than requested gso_size, and return EMSGSIZE instead of EINVAL
on MTU/PMTU check failure to be more specific on the error cause.

Fixes: 4094871db1d6 ("udp: only do GSO if # of segs > 1")
Signed-off-by: Yan Zhai 
Suggested-by: Willem de Bruijn 
Reviewed-by: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

ktest.pl: Check kernelrelease return in get_version

2025-03-13T11:43:01+00:00

commit a4e17a8f239a545c463f8ec27db4ed6e74b31841 upstream.

In the case of a test that uses the special option ${KERNEL_VERSION} in one
of its settings but has no configuration available in ${OUTPUT_DIR}, for
example if it's a new empty directory, then the `make kernelrelease` call
will fail and the subroutine will chomp an empty string, silently. Fix that
by adding an empty configuration and retrying.

Cc: stable@vger.kernel.org
Cc: John Hawley 
Fixes: 5f9b6ced04a4e ("ktest: Bisecting, install modules, add logging")
Link: https://lore.kernel.org/20241205-ktest_kver_fallback-v2-1-869dae4c7777@suse.com
Signed-off-by: Ricardo B. Marliere 
Signed-off-by: Steven Rostedt 
Signed-off-by: Greg Kroah-Hartman

perf trace: Fix runtime error of index out of bounds

2025-03-13T11:43:00+00:00

[ Upstream commit c7b87ce0dd10b64b68a0b22cb83bbd556e28fe81 ]

libtraceevent parses and returns an array of argument fields, sometimes
larger than RAW_SYSCALL_ARGS_NUM (6) because it includes "__syscall_nr",
idx will traverse to index 6 (7th element) whereas sc->fmt->arg holds 6
elements max, creating an out-of-bounds access. This runtime error is
found by UBsan. The error message:

  $ sudo UBSAN_OPTIONS=print_stacktrace=1 ./perf trace -a --max-events=1
  builtin-trace.c:1966:35: runtime error: index 6 out of bounds for type 'syscall_arg_fmt [6]'
    #0 0x5c04956be5fe in syscall__alloc_arg_fmts /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:1966
    #1 0x5c04956c0510 in trace__read_syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2110
    #2 0x5c04956c372b in trace__syscall_info /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:2436
    #3 0x5c04956d2f39 in trace__init_syscalls_bpf_prog_array_maps /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:3897
    #4 0x5c04956d6d25 in trace__run /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:4335
    #5 0x5c04956e112e in cmd_trace /home/howard/hw/linux-perf/tools/perf/builtin-trace.c:5502
    #6 0x5c04956eda7d in run_builtin /home/howard/hw/linux-perf/tools/perf/perf.c:351
    #7 0x5c04956ee0a8 in handle_internal_command /home/howard/hw/linux-perf/tools/perf/perf.c:404
    #8 0x5c04956ee37f in run_argv /home/howard/hw/linux-perf/tools/perf/perf.c:448
    #9 0x5c04956ee8e9 in main /home/howard/hw/linux-perf/tools/perf/perf.c:556
    #10 0x79eb3622a3b7 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
    #11 0x79eb3622a47a in __libc_start_main_impl ../csu/libc-start.c:360
    #12 0x5c04955422d4 in _start (/home/howard/hw/linux-perf/tools/perf/perf+0x4e02d4) (BuildId: 5b6cab2d59e96a4341741765ad6914a4d784dbc6)

     0.000 ( 0.014 ms): Chrome_ChildIO/117244 write(fd: 238, buf: !, count: 1)                                      = 1

Fixes: 5e58fcfaf4c6 ("perf trace: Allow allocating sc->arg_fmt even without the syscall tracepoint")
Signed-off-by: Howard Chu 
Link: https://lore.kernel.org/r/20250122025519.361873-1-howardchu95@gmail.com
Signed-off-by: Namhyung Kim 
Signed-off-by: Sasha Levin

perf report: Fix misleading help message about --demangle

2025-03-13T11:42:56+00:00

[ Upstream commit ac0ac75189a4d6a29a2765a7adbb62bc6cc650c7 ]

The wrong help message may mislead users. This commit fixes it.

Fixes: 328ccdace8855289 ("perf report: Add --no-demangle option")
Reviewed-by: Namhyung Kim 
Signed-off-by: Jiachen Zhang 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: https://lore.kernel.org/r/20250109152220.1869581-1-me@jcix.top
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf top: Don't complain about lack of vmlinux when not resolving some kernel samples

2025-03-13T11:42:56+00:00

[ Upstream commit 058b38ccd2af9e5c95590b018e8425fa148d7aca ]

Recently we got a case where a kernel sample wasn't being resolved due
to a bug that was not setting the end address on kernel functions
implemented in assembly (see Link: tag), and then those were not being
found by machine__resolve() -> map__find_symbol().

So we ended up with:

  # perf top --stdio
  PerfTop: 0 irqs/s  kernel: 0%  exact: 0% lost: 0/0 drop: 0/0 [cycles/P]
  -----------------------------------------------------------------------

  Warning:
  A vmlinux file was not found.
  Kernel samples will not be resolved.
  ^Z
  [1]+  Stopped                 perf top --stdio
  #

But then resolving all other kernel symbols.

So just fixup the logic to only print that warning when there are no
symbols in the kernel map.

Fixes: d88205db9caa0e9d ("perf dso: Add dso__has_symbols() method")
Reviewed-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Christophe Leroy 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: Kan Liang 
Link: https://lore.kernel.org/lkml/Z3buKhcCsZi3_aGb@x1
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin