linux-stable.git/tools, branch v5.4.301

rseq/selftests: Use weak symbol reference, not definition, to link with glibc

2025-10-29T12:59:54+00:00

commit a001cd248ab244633c5fabe4f7c707e13fc1d1cc upstream.

Add "extern" to the glibc-defined weak rseq symbols to convert the rseq
selftest's usage from weak symbol definitions to weak symbol _references_.
Effectively re-defining the glibc symbols wreaks havoc when building with
-fno-common, e.g. generates segfaults when running multi-threaded programs,
as dynamically linked applications end up with multiple versions of the
symbols.

Building with -fcommon, which until recently has the been the default for
GCC and clang, papers over the bug by allowing the linker to resolve the
weak/tentative definition to glibc's "real" definition.

Note, the symbol itself (or rather its address), not the value of the
symbol, is set to 0/NULL for unresolved weak symbol references, as the
symbol doesn't exist and thus can't have a value.  Check for a NULL rseq
size pointer to handle the scenario where the test is statically linked
against a libc that doesn't support rseq in any capacity.

Fixes: 3bcbc20942db ("selftests/rseq: Play nice with binaries statically linked against glibc 2.35+")
Reported-by: Thomas Gleixner 
Suggested-by: Florian Weimer 
Signed-off-by: Sean Christopherson 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Mathieu Desnoyers 
Cc: stable@vger.kernel.org
Closes: https://lore.kernel.org/all/87frdoybk4.ffs@tglx
Signed-off-by: Greg Kroah-Hartman

tools build: Align warning options with perf

2025-10-29T12:59:51+00:00

[ Upstream commit 53d067feb8c4f16d1f24ce3f4df4450bb18c555f ]

The feature test programs are built without enabling '-Wall -Werror'
options. As a result, a feature may appear to be available, but later
building in perf can fail with stricter checks.

Make the feature test program use the same warning options as perf.

Fixes: 1925459b4d92 ("tools build: Fix feature Makefile issues with 'O='")
Signed-off-by: Leo Yan 
Reviewed-by: Ian Rogers 
Link: https://lore.kernel.org/r/20251006-perf_build_android_ndk-v3-1-4305590795b2@arm.com
Cc: Palmer Dabbelt 
Cc: Albert Ou 
Cc: Alexandre Ghiti 
Cc: Nick Desaulniers 
Cc: Justin Stitt 
Cc: Bill Wendling 
Cc: Adrian Hunter 
Cc: Arnaldo Carvalho de Melo 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Nathan Chancellor 
Cc: James Clark 
Cc: linux-riscv@lists.infradead.org
Cc: llvm@lists.linux.dev
Cc: Paul Walmsley 
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf session: Fix handling when buffer exceeds 2 GiB

2025-10-29T12:59:50+00:00

[ Upstream commit c17dda8013495d8132c976cbf349be9949d0fbd1 ]

If a user specifies an AUX buffer larger than 2 GiB, the returned size
may exceed 0x80000000. Since the err variable is defined as a signed
32-bit integer, such a value overflows and becomes negative.

As a result, the perf record command reports an error:

  0x146e8 [0x30]: failed to process type: 71 [Unknown error 183711232]

Change the type of the err variable to a signed 64-bit integer to
accommodate large buffer sizes correctly.

Fixes: d5652d865ea734a1 ("perf session: Add ability to skip 4GiB or more")
Reported-by: Tamas Zsoldos 
Signed-off-by: Leo Yan 
Acked-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Link: https://lore.kernel.org/r/20250808-perf_fix_big_buffer_size-v1-1-45f45444a9a4@arm.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf util: Fix compression checks returning -1 as bool

2025-10-29T12:59:50+00:00

[ Upstream commit 43fa1141e2c1af79c91aaa4df03e436c415a6fc3 ]

The lzma_is_compressed and gzip_is_compressed functions are declared
to return a "bool" type, but in case of an error (e.g., file open
failure), they incorrectly returned -1.

A bool type is a boolean value that is either true or false.
Returning -1 for a bool return type can lead to unexpected behavior
and may violate strict type-checking in some compilers.

Fix the return value to be false in error cases, ensuring the function
adheres to its declared return type improves for preventing potential
bugs related to type mismatch.

Fixes: 4b57fd44b61beb51 ("perf tools: Add lzma_is_compressed function")
Reviewed-by: Ian Rogers 
Signed-off-by: Yunseong Kim 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Namhyung Kim 
Cc: Stephen Brennan 
Link: https://lore.kernel.org/r/20250822162506.316844-3-ysk@kzalloc.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

selftests: watchdog: skip ping loop if WDIOF_KEEPALIVEPING not supported

2025-10-29T12:59:46+00:00

[ Upstream commit e8cfc524eaf3c0ed88106177edb6961e202e6716 ]

Check if watchdog device supports WDIOF_KEEPALIVEPING option before
entering keep_alive() ping test loop. Fix watchdog-test silently looping
if ioctl based ping is not supported by the device. Exit from test in
such case instead of getting stuck in loop executing failing keep_alive()

watchdog_info:
 identity:              m41t93 rtc Watchdog
 firmware_version:      0
Support/Status: Set timeout (in seconds)
Support/Status: Watchdog triggers a management or other external alarm not a reboot

Watchdog card disabled.
Watchdog timeout set to 5 seconds.
Watchdog ping rate set to 2 seconds.
Watchdog card enabled.
WDIOC_KEEPALIVE not supported by this device

without this change
Watchdog card disabled.
Watchdog timeout set to 5 seconds.
Watchdog ping rate set to 2 seconds.
Watchdog card enabled.
Watchdog Ticking Away!
(Where test stuck here forver silently)

Updated change log at commit time:
Shuah Khan 

Link: https://lore.kernel.org/r/20250914152840.GA3047348@bhairav-test.ee.iitb.ac.in
Fixes: d89d08ffd2c5 ("selftests: watchdog: Fix ioctl SET* error paths to take oneshot exit path")
Signed-off-by: Akhilesh Patil 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

perf subcmd: avoid crash in exclude_cmds when excludes is empty

2025-10-29T12:59:45+00:00

[ Upstream commit a5edf3550f4260504b7e0ab3d40d13ffe924b773 ]

When cross-compiling the perf tool for ARM64, `perf help` may crash
with the following assertion failure:

  help.c:122: exclude_cmds: Assertion `cmds->names[ci] == NULL' failed.

This happens when the perf binary is not named exactly "perf" or when
multiple "perf-*" binaries exist in the same directory. In such cases,
the `excludes` command list can be empty, which leads to the final
assertion in exclude_cmds() being triggered.

Add a simple guard at the beginning of exclude_cmds() to return early
if excludes->cnt is zero, preventing the crash.

Signed-off-by: hupu 
Reported-by: Guilherme Amadio 
Reviewed-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20250909094953.106706-1-amadio@gentoo.org
Signed-off-by: Namhyung Kim 
Signed-off-by: Sasha Levin

act_mirred: use the backlog for nested calls to mirred ingress

2025-08-28T14:21:36+00:00

[ Upstream commit ca22da2fbd693b54dc8e3b7b54ccc9f7e9ba3640 ]

William reports kernel soft-lockups on some OVS topologies when TC mirred
egress->ingress action is hit by local TCP traffic [1].
The same can also be reproduced with SCTP (thanks Xin for verifying), when
client and server reach themselves through mirred egress to ingress, and
one of the two peers sends a "heartbeat" packet (from within a timer).

Enqueueing to backlog proved to fix this soft lockup; however, as Cong
noticed [2], we should preserve - when possible - the current mirred
behavior that counts as "overlimits" any eventual packet drop subsequent to
the mirred forwarding action [3]. A compromise solution might use the
backlog only when tcf_mirred_act() has a nest level greater than one:
change tcf_mirred_forward() accordingly.

Also, add a kselftest that can reproduce the lockup and verifies TC mirred
ability to account for further packet drops after TC mirred egress->ingress
(when the nest level is 1).

 [1] https://lore.kernel.org/netdev/33dc43f587ec1388ba456b4915c75f02a8aae226.1663945716.git.dcaratti@redhat.com/
 [2] https://lore.kernel.org/netdev/Y0w%2FWWY60gqrtGLp@pop-os.localdomain/
 [3] such behavior is not guaranteed: for example, if RPS or skb RX
     timestamping is enabled on the mirred target device, the kernel
     can defer receiving the skb and return NET_RX_SUCCESS inside
     tcf_mirred_forward().

Reported-by: William Zhao 
CC: Xin Long 
Signed-off-by: Davide Caratti 
Reviewed-by: Marcelo Ricardo Leitner 
Acked-by: Jamal Hadi Salim 
Signed-off-by: Paolo Abeni 
[ skulkarni: Adjusted patch for file 'tc_actions.sh' wrt the mainline commit ]
Signed-off-by: Shubham Kulkarni 
Signed-off-by: Greg Kroah-Hartman

selftests: forwarding: tc_actions.sh: add matchall mirror test

2025-08-28T14:21:36+00:00

[ Upstream commit 075c8aa79d541ea08c67a2e6d955f6457e98c21c ]

Add test for matchall classifier with mirred egress mirror action.

Signed-off-by: Jiri Pirko 
Signed-off-by: Ido Schimmel 
Signed-off-by: David S. Miller 
Stable-dep-of: ca22da2fbd69 ("act_mirred: use the backlog for nested calls to mirred ingress")
Signed-off-by: Shubham Kulkarni 
Signed-off-by: Greg Kroah-Hartman

ktest.pl: Prevent recursion of default variable options

2025-08-28T14:21:26+00:00

[ Upstream commit 61f7e318e99d3b398670518dd3f4f8510d1800fc ]

If a default variable contains itself, do not recurse on it.

For example:

  ADD_CONFIG := ${CONFIG_DIR}/temp_config
  DEFAULTS
  ADD_CONFIG = ${CONFIG_DIR}/default_config ${ADD_CONFIG}

The above works because the temp variable ADD_CONFIG (is a temp because it
is created with ":=") is already defined, it will be substituted in the
variable option. But if it gets commented out:

  # ADD_CONFIG := ${CONFIG_DIR}/temp_config
  DEFAULTS
  ADD_CONFIG = ${CONFIG_DIR}/default_config ${ADD_CONFIG}

Then the above will go into a recursive loop where ${ADD_CONFIG} will
get replaced with the current definition of ADD_CONFIG which contains the
${ADD_CONFIG} and that will also try to get converted. ktest.pl will error
after 100 attempts of recursion and fail.

When replacing a variable with the default variable, if the default
variable contains itself, do not replace it.

Cc: "John Warthog9 Hawley" 
Cc: Dhaval Giani 
Cc: Greg KH 
Link: https://lore.kernel.org/20250718202053.732189428@kernel.org
Signed-off-by: Steven Rostedt 
Signed-off-by: Sasha Levin

pm: cpupower: Fix the snapshot-order of tsc,mperf, clock in mperf_stop()

2025-08-28T14:21:25+00:00

[ Upstream commit cda7ac8ce7de84cf32a3871ba5f318aa3b79381e ]

In the function mperf_start(), mperf_monitor snapshots the time, tsc
and finally the aperf,mperf MSRs. However, this order of snapshotting
in is reversed in mperf_stop(). As a result, the C0 residency (which
is computed as delta_mperf * 100 / delta_tsc) is under-reported on
CPUs that is 100% busy.

Fix this by snapshotting time, tsc and then aperf,mperf in
mperf_stop() in the same order as in mperf_start().

Link: https://lore.kernel.org/r/20250612122355.19629-2-gautham.shenoy@amd.com
Signed-off-by: Gautham R. Shenoy 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin