From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yafang Shao Subject: [RFC PATCH bpf-next 5/8] selftests/bpf: Fix issues in setup_classid_environment() Date: Fri, 22 Sep 2023 11:28:43 +0000 Message-ID: <20230922112846.4265-6-laoar.shao@gmail.com> References: <20230922112846.4265-1-laoar.shao@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1695382155; x=1695986955; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=YxmghcOcb4Lv1mKG5g6exWWWkajf/SPl1xKizlQXNEE=; b=C1yvSKtcf8b8zMSnHslJ+/+kgpI+4RtJkLSPcVu3s31pgu2yciBb853YLfg8Lfb6rU MkWmrhENjSgJgfisqGTO73tewSBuTZTAfI8gtZ54IHXUuo7lhUoIykDbzUleUjAJ5Xd7 yMbPu2xXEF11kqSVobl1JcmVSd3dt+ubrbCSlCKL066r8hPFEA+fz4MpW8kFSYxs3jVV ZJZOlccuxf1zBb1t5E03PzjrwfMUE/j26fJr1Xt05lEVd1Mk25A18rjs5eraYQBQRIZN YDUujeAcVrW8NpsMp2uCnTfRKy+XTnQudb+96jgTI6b8ScJVklO5zbE4UBMj2b/dQRHM CQpQ== In-Reply-To: <20230922112846.4265-1-laoar.shao-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> List-ID: Content-Type: text/plain; charset="us-ascii" To: ast-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, daniel-FeC+5ew28dpmcu3hnIyYJQ@public.gmane.org, john.fastabend-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, andrii-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, martin.lau-fxUVXftIFDnyG1zEObXtfA@public.gmane.org, song-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, yonghong.song-fxUVXftIFDnyG1zEObXtfA@public.gmane.org, kpsingh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, sdf-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, haoluo-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, jolsa-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, lizefan.x-EC8Uxl6Npydl57MIdRCFDg@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, yosryahmed-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, mkoutny-IBi9RG/b67k@public.gmane.org Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, bpf-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Yafang Shao If the net_cls subsystem is already mounted, attempting to mount it again in setup_classid_environment() will result in a failure with the error code EBUSY. Despite this, tmpfs will have been successfully mounted at /sys/fs/cgroup/net_cls. Consequently, the /sys/fs/cgroup/net_cls directory will be empty, causing subsequent setup operations to fail. Here's an error log excerpt illustrating the issue when net_cls has already been mounted at /sys/fs/cgroup/net_cls prior to running setup_classid_environment(): - Before that change $ tools/testing/selftests/bpf/test_progs --name=cgroup_v1v2 test_cgroup_v1v2:PASS:server_fd 0 nsec test_cgroup_v1v2:PASS:client_fd 0 nsec test_cgroup_v1v2:PASS:cgroup_fd 0 nsec test_cgroup_v1v2:PASS:server_fd 0 nsec run_test:PASS:skel_open 0 nsec run_test:PASS:prog_attach 0 nsec test_cgroup_v1v2:PASS:cgroup-v2-only 0 nsec (cgroup_helpers.c:248: errno: No such file or directory) Opening Cgroup Procs: /sys/fs/cgroup/net_cls/cgroup.procs (cgroup_helpers.c:540: errno: No such file or directory) Opening cgroup classid: /sys/fs/cgroup/net_cls/cgroup-test-work-dir/net_cls.classid run_test:PASS:skel_open 0 nsec run_test:PASS:prog_attach 0 nsec (cgroup_helpers.c:248: errno: No such file or directory) Opening Cgroup Procs: /sys/fs/cgroup/net_cls/cgroup-test-work-dir/cgroup.procs run_test:FAIL:join_classid unexpected error: 1 (errno 2) test_cgroup_v1v2:FAIL:cgroup-v1v2 unexpected error: -1 (errno 2) (cgroup_helpers.c:248: errno: No such file or directory) Opening Cgroup Procs: /sys/fs/cgroup/net_cls/cgroup.procs #44 cgroup_v1v2:FAIL Summary: 0/0 PASSED, 0 SKIPPED, 1 FAILED - After that change $ tools/testing/selftests/bpf/test_progs --name=cgroup_v1v2 #44 cgroup_v1v2:OK Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Yafang Shao --- tools/testing/selftests/bpf/cgroup_helpers.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/bpf/cgroup_helpers.c b/tools/testing/selftests/bpf/cgroup_helpers.c index 24ba56d42f2d..9c36d1db9f94 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.c +++ b/tools/testing/selftests/bpf/cgroup_helpers.c @@ -518,10 +518,20 @@ int setup_classid_environment(void) return 1; } - if (mount("net_cls", NETCLS_MOUNT_PATH, "cgroup", 0, "net_cls") && - errno != EBUSY) { - log_err("mount cgroup net_cls"); - return 1; + if (mount("net_cls", NETCLS_MOUNT_PATH, "cgroup", 0, "net_cls")) { + if (errno != EBUSY) { + log_err("mount cgroup net_cls"); + return 1; + } + + if (rmdir(NETCLS_MOUNT_PATH)) { + log_err("rmdir cgroup net_cls"); + return 1; + } + if (umount(CGROUP_MOUNT_DFLT)) { + log_err("umount cgroup base"); + return 1; + } } cleanup_classid_environment(); -- 2.30.1 (Apple Git-130)