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From:   =?utf-8?q?Thomas_Wei=C3=9Fschuh?= <linux@weissschuh.net>
Date:   Fri, 26 May 2023 08:30:36 +0200
Subject: [PATCH 2/2] selftests/nolibc: prevent coredumps during test
 execution
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Message-Id: <20230526-nolibc-test-no-dump-v1-2-62e724a96db2@weissschuh.net>
References: <20230526-nolibc-test-no-dump-v1-0-62e724a96db2@weissschuh.net>
In-Reply-To: <20230526-nolibc-test-no-dump-v1-0-62e724a96db2@weissschuh.net>
To:     Willy Tarreau <w@1wt.eu>, Shuah Khan <shuah@kernel.org>
Cc:     linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
        =?utf-8?q?Thomas_Wei=C3=9Fschuh?= <linux@weissschuh.net>
Precedence: bulk

The child process forked during stackprotector tests intentionally gets
killed with SIGABRT. By default this will trigger writing a coredump.
The writing of the coredump can spam the systems coredump machinery and
take some time.

Timings for the full run of nolibc-test:
Before: 200ms
After:   20ms

This is on a desktop x86 system with systemd-coredumpd enabled.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/nolibc-test.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 76a9a0f362b1..40fb684eaac9 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -831,6 +831,7 @@ static int run_protection(int min, int max)
 		close(STDOUT_FILENO);
 		close(STDERR_FILENO);
 
+		prctl(PR_SET_DUMPABLE, 0, 0, 0, 0);
 		smash_stack();
 		return 1;
 

-- 
2.40.1