From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	patches@lists.linux.dev,
	James Clark <james.clark@linaro.org>,
	Ian Rogers <irogers@google.com>,
	Namhyung Kim <namhyung@kernel.org>,
	Sasha Levin <sashal@kernel.org>
Subject: [PATCH 6.12 1351/1376] perf test: Dont signal all processes on system when interrupting tests
Date: Sat, 12 Sep 2026 09:02:57 +0200
Message-ID: <20260912065637.643140593@linuxfoundation.org>
In-Reply-To: <20260912065607.535295758@linuxfoundation.org>
References: <20260912065607.535295758@linuxfoundation.org>
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6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: James Clark <james.clark@linaro.org>

[ Upstream commit f54cd8f43f55c0274c5b51509aff39675639c2e1 ]

This signal handler loops over all tests on ctrl-C, but it's active
while the test list is being constructed. process.pid is 0, then -1,
then finally set to the child pid on fork. If the Ctrl-C is received
during this point a kill(-1, SIGINT) can be sent which affects all
processes.

Make sure the child has forked first before forwarding the signal. This
can be reproduced with ctrl-C immediately after launching perf test
which terminates the ssh connection.

Fixes: 553d5efeb341 ("perf test: Add a signal handler to kill forked child processes")
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20241129151948.3199732-1-james.clark@linaro.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/perf/tests/builtin-test.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 17f723f04926b..e35b138f4bd0e 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -504,7 +504,7 @@ static int __cmd_test(struct test_suite **suites, int argc, const char *argv[],
 		for (size_t x = 0; x < num_tests; x++) {
 			struct child_test *child_test = child_tests[x];
 
-			if (!child_test)
+			if (!child_test || child_test->process.pid <= 0)
 				continue;
 
 			pr_debug3("Killing %d pid %d\n",
-- 
2.53.0