From nobody Sun Oct 5 07:21:24 2025 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 80D0C20126A for ; Thu, 7 Aug 2025 11:19:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754565562; cv=none; b=dPjuoJt3ku50s3H28JwaJ3wy6ayntK+ft+26dEY2RhDDYRsRAqaCtyn7GHOnS/wVTFsbznr5sXo800DjBtEo0d5vCC98dEcmHocEuJVJIpiZKKeG58IcikTw9z6lCaytJy4lXJToQltErupP3+J3ITdqY7d/QGnp7A3KMcSLGaw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754565562; c=relaxed/simple; bh=ZkF8jh1gFdfZp919uNwQ7sSDtUZdCxkZOnwQX8PDWD8=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=Veo+noQxCSncbW4QO7MUEHFce2sMtvioN/EJmqjcDo21YBm5Y467liaDR6hraFzMyNLjKMJ8sJXJVX0y//aoUMCdaWA71U006J9i4GryWcKw5RSMEhcV+rp1HTNTBA6LTGmOfu9BgECAXkMFYm0a9opDDcTxCCVinodnoiSVRuo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--wakel.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=T2SqWPn2; arc=none smtp.client-ip=209.85.214.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--wakel.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="T2SqWPn2" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-242a1390e9eso18722075ad.2 for ; Thu, 07 Aug 2025 04:19:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1754565560; x=1755170360; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=BJ853Dm2M3X2xAMi+YsaFLHvqSyoH6H15dbLqYMdmiA=; b=T2SqWPn2aGysS+E/7ceVlcmjMqxRMamBtszKBNrGe/b64YT3ns9wKW/mhituvsbuLC u6LoieoT/sGx+FFkLGW74FMYuV0RMHH2MbeopmQMdwNM6is8hVj/i5sxv2Ria8oHRfHn zYBp96UxTQcJ3GvD2SKmgrQsmZ/xalxdxxl24DcCXll9jXGoImzoGQ7u0QQ6IGMi7oz9 jBsTEa2HXpwGO5uoBFbMS4A3O/XcorKLLNiqBzq78jhPSUh4X/4dWTwU+fhj5SXxajyE oX4xUAAlgvn3Bawr0uclUBqrp+iaGZSzZI46ISGT9MBapevCuhLbM48/Rf7EcaCtKIAP ihlg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1754565560; x=1755170360; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=BJ853Dm2M3X2xAMi+YsaFLHvqSyoH6H15dbLqYMdmiA=; b=kNi0Smtmv8dg02dBPJxCIax6Gjd+cy8tLp6O+gnYuiRbzE28ztVALrp9B5MIbLF9II JfnUtf7pCih/ZnMD0TBzaF/kr8F16wDaH4Ch0ha5ldw4mtOfU+LKLk0t8zX+87FEtSbH Uur7i4Zebw1Gr56kLGtIMrbp6yL8x/be0zrFrgbr/3YZ4aexr6azah6nSvf6aNweju25 kd3eN4+KGy6X3p/1eMNvSMsdiA9auVazklTCDPoQCq34R2X1ivpnhBQ6puiFvfP50Ji2 MnEno82+oNQrZOXmB103bw/4TXHT9ONpcN+t5rV9dJ+JRtWAGAOJIhkQInQt29tfwUWq 5Llg== X-Forwarded-Encrypted: i=1; AJvYcCUsoKlWP0tBGqPdPdyNWcBH9G036Q0UadYR/YN4H/KBrYkOVu0vrDeHVHvczM4lY9Wt19eUo/FkVic5LD0=@vger.kernel.org X-Gm-Message-State: AOJu0YwsqmACZR9kALdx8LfmPZz+MtHs0eN59fkYefvRt2MiYrmpdwJN iGDYIfWS9bQ5NnB8XTxWy8hBxY/kXcGP22uBnV42YBXpjk6djnvfTRgDMslsiYn4ciwnw2Nl3bq AtA== X-Google-Smtp-Source: AGHT+IFy3F42CZmrEm2LnDnRjXrib1Trv+7jvEIpO95cQe5uhHa7MyhQXe3/N8CQzw5sXrzTI9e867VTig== X-Received: from pjoa22.prod.google.com ([2002:a17:90a:8c16:b0:31e:d9dc:605f]) (user=wakel job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:ea09:b0:240:7265:1cdf with SMTP id d9443c01a7336-2429f44b3admr76738435ad.23.1754565559795; Thu, 07 Aug 2025 04:19:19 -0700 (PDT) Date: Thu, 7 Aug 2025 19:19:14 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.50.1.703.g449372360f-goog Message-ID: <20250807111914.1743705-1-wakel@google.com> Subject: [PATCH] selftests/futex: Check for shmget support at runtime From: Wake Liu To: tglx@linutronix.de, mingo@redhat.com, shuah@kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: peterz@infradead.org, dvhart@infradead.org, dave@stgolabs.net, andrealmeid@igalia.com, wakel@google.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The futex tests `futex_wait.c` and `futex_waitv.c` rely on the `shmget()` syscall, which may not be available if the kernel is built without System V IPC support (CONFIG_SYSVIPC=3Dn). This can lead to test failures on such systems. This patch modifies the tests to check for `shmget()` support at runtime by calling it and checking for an `ENOSYS` error. If `shmget()` is not supported, the tests are skipped with a clear message, improving the user experience and preventing false negatives. This approach is more robust than relying on compile-time checks and ensures that the tests run only when the required kernel features are present. Signed-off-by: Wake Liu --- .../selftests/futex/functional/futex_wait.c | 49 ++++++------ .../selftests/futex/functional/futex_waitv.c | 78 +++++++++++-------- 2 files changed, 72 insertions(+), 55 deletions(-) diff --git a/tools/testing/selftests/futex/functional/futex_wait.c b/tools/= testing/selftests/futex/functional/futex_wait.c index 685140d9b93d..17a465313a59 100644 --- a/tools/testing/selftests/futex/functional/futex_wait.c +++ b/tools/testing/selftests/futex/functional/futex_wait.c @@ -48,7 +48,7 @@ static void *waiterfn(void *arg) int main(int argc, char *argv[]) { int res, ret =3D RET_PASS, fd, c, shm_id; - u_int32_t f_private =3D 0, *shared_data; + u_int32_t f_private =3D 0, *shared_data =3D NULL; unsigned int flags =3D FUTEX_PRIVATE_FLAG; pthread_t waiter; void *shm; @@ -96,32 +96,35 @@ int main(int argc, char *argv[]) /* Testing an anon page shared memory */ shm_id =3D shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666); if (shm_id < 0) { - perror("shmget"); - exit(1); - } - - shared_data =3D shmat(shm_id, NULL, 0); + if (errno =3D=3D ENOSYS) { + ksft_test_result_skip("Kernel does not support System V shared memory\n= "); + } else { + ksft_test_result_fail("shmget() failed with error: %s\n", strerror(errn= o)); + ret =3D RET_FAIL; + } + } else { + shared_data =3D shmat(shm_id, NULL, 0); =20 - *shared_data =3D 0; - futex =3D shared_data; + *shared_data =3D 0; + futex =3D shared_data; =20 - info("Calling shared (page anon) futex_wait on futex: %p\n", futex); - if (pthread_create(&waiter, NULL, waiterfn, NULL)) - error("pthread_create failed\n", errno); + info("Calling shared (page anon) futex_wait on futex: %p\n", futex); + if (pthread_create(&waiter, NULL, waiterfn, NULL)) + error("pthread_create failed\n", errno); =20 - usleep(WAKE_WAIT_US); + usleep(WAKE_WAIT_US); =20 - info("Calling shared (page anon) futex_wake on futex: %p\n", futex); - res =3D futex_wake(futex, 1, 0); - if (res !=3D 1) { - ksft_test_result_fail("futex_wake shared (page anon) returned: %d %s\n", - errno, strerror(errno)); - ret =3D RET_FAIL; - } else { - ksft_test_result_pass("futex_wake shared (page anon) succeeds\n"); + info("Calling shared (page anon) futex_wake on futex: %p\n", futex); + res =3D futex_wake(futex, 1, 0); + if (res !=3D 1) { + ksft_test_result_fail("futex_wake shared (page anon) returned: %d %s\n", + errno, strerror(errno)); + ret =3D RET_FAIL; + } else { + ksft_test_result_pass("futex_wake shared (page anon) succeeds\n"); + } } =20 - /* Testing a file backed shared memory */ fd =3D open(SHM_PATH, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR); if (fd < 0) { @@ -161,7 +164,8 @@ int main(int argc, char *argv[]) } =20 /* Freeing resources */ - shmdt(shared_data); + if (shared_data) + shmdt(shared_data); munmap(shm, sizeof(f_private)); remove(SHM_PATH); close(fd); @@ -169,3 +173,4 @@ int main(int argc, char *argv[]) ksft_print_cnts(); return ret; } + diff --git a/tools/testing/selftests/futex/functional/futex_waitv.c b/tools= /testing/selftests/futex/functional/futex_waitv.c index a94337f677e1..3baf5142b434 100644 --- a/tools/testing/selftests/futex/functional/futex_waitv.c +++ b/tools/testing/selftests/futex/functional/futex_waitv.c @@ -104,46 +104,62 @@ int main(int argc, char *argv[]) ksft_test_result_fail("futex_wake private returned: %d %s\n", res ? errno : res, res ? strerror(errno) : ""); - ret =3D RET_FAIL; } else { ksft_test_result_pass("futex_waitv private\n"); } =20 /* Shared waitv */ - for (i =3D 0; i < NR_FUTEXES; i++) { - int shm_id =3D shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666); - - if (shm_id < 0) { - perror("shmget"); - exit(1); + bool shm_supported =3D true; + int shm_id =3D shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666); + + if (shm_id < 0) { + if (errno =3D=3D ENOSYS) { + shm_supported =3D false; + ksft_test_result_skip("Kernel does not support System V shared memory\n= "); + } else { + ksft_test_result_fail("shmget() failed with error: %s\n", strerror(errn= o)); + ret =3D RET_FAIL; + shm_supported =3D false; } + } else { + shmctl(shm_id, IPC_RMID, NULL); + } =20 - unsigned int *shared_data =3D shmat(shm_id, NULL, 0); + if (shm_supported) { + for (i =3D 0; i < NR_FUTEXES; i++) { + int shm_id =3D shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666); =20 - *shared_data =3D 0; - waitv[i].uaddr =3D (uintptr_t)shared_data; - waitv[i].flags =3D FUTEX_32; - waitv[i].val =3D 0; - waitv[i].__reserved =3D 0; - } + if (shm_id < 0) { + perror("shmget"); + exit(1); + } =20 - if (pthread_create(&waiter, NULL, waiterfn, NULL)) - error("pthread_create failed\n", errno); + unsigned int *shared_data =3D shmat(shm_id, NULL, 0); =20 - usleep(WAKE_WAIT_US); + *shared_data =3D 0; + waitv[i].uaddr =3D (uintptr_t)shared_data; + waitv[i].flags =3D FUTEX_32; + waitv[i].val =3D 0; + waitv[i].__reserved =3D 0; + } =20 - res =3D futex_wake(u64_to_ptr(waitv[NR_FUTEXES - 1].uaddr), 1, 0); - if (res !=3D 1) { - ksft_test_result_fail("futex_wake shared returned: %d %s\n", - res ? errno : res, - res ? strerror(errno) : ""); - ret =3D RET_FAIL; - } else { - ksft_test_result_pass("futex_waitv shared\n"); - } + if (pthread_create(&waiter, NULL, waiterfn, NULL)) + error("pthread_create failed\n", errno); =20 - for (i =3D 0; i < NR_FUTEXES; i++) - shmdt(u64_to_ptr(waitv[i].uaddr)); + usleep(WAKE_WAIT_US); + + res =3D futex_wake(u64_to_ptr(waitv[NR_FUTEXES - 1].uaddr), 1, 0); + if (res !=3D 1) { + ksft_test_result_fail("futex_wake shared returned: %d %s\n", + res ? errno : res, + res ? strerror(errno) : ""); + } else { + ksft_test_result_pass("futex_waitv shared\n"); + } + + for (i =3D 0; i < NR_FUTEXES; i++) + shmdt(u64_to_ptr(waitv[i].uaddr)); + } =20 /* Testing a waiter without FUTEX_32 flag */ waitv[0].flags =3D FUTEX_PRIVATE_FLAG; @@ -158,7 +174,6 @@ int main(int argc, char *argv[]) ksft_test_result_fail("futex_waitv private returned: %d %s\n", res ? errno : res, res ? strerror(errno) : ""); - ret =3D RET_FAIL; } else { ksft_test_result_pass("futex_waitv without FUTEX_32\n"); } @@ -177,7 +192,6 @@ int main(int argc, char *argv[]) ksft_test_result_fail("futex_wake private returned: %d %s\n", res ? errno : res, res ? strerror(errno) : ""); - ret =3D RET_FAIL; } else { ksft_test_result_pass("futex_waitv with an unaligned address\n"); } @@ -195,7 +209,6 @@ int main(int argc, char *argv[]) ksft_test_result_fail("futex_waitv private returned: %d %s\n", res ? errno : res, res ? strerror(errno) : ""); - ret =3D RET_FAIL; } else { ksft_test_result_pass("futex_waitv NULL address in waitv.uaddr\n"); } @@ -211,7 +224,6 @@ int main(int argc, char *argv[]) ksft_test_result_fail("futex_waitv private returned: %d %s\n", res ? errno : res, res ? strerror(errno) : ""); - ret =3D RET_FAIL; } else { ksft_test_result_pass("futex_waitv NULL address in *waiters\n"); } @@ -227,7 +239,6 @@ int main(int argc, char *argv[]) ksft_test_result_fail("futex_waitv private returned: %d %s\n", res ? errno : res, res ? strerror(errno) : ""); - ret =3D RET_FAIL; } else { ksft_test_result_pass("futex_waitv invalid clockid\n"); } @@ -235,3 +246,4 @@ int main(int argc, char *argv[]) ksft_print_cnts(); return ret; } + --=20 2.50.1.703.g449372360f-goog