From 0bc5f001dbf25ea264a9b61aafd3d7362f53b7be Mon Sep 17 00:00:00 2001 From: Dan Streetman Date: Sat, 21 Mar 2020 11:19:44 -0400 Subject: [PATCH] cgroup-util: check for SYSFS_MAGIC when detecting cgroup format When nothing at all is mounted at /sys/fs/cgroup, the fs.f_type is SYSFS_MAGIC (0x62656572) which results in the confusing debug log: "Unknown filesystem type 62656572 mounted on /sys/fs/cgroup." Instead, if the f_type is SYSFS_MAGIC, a more accurate message is: "No filesystem is currently mounted on /sys/fs/cgroup." --- src/basic/cgroup-util.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c index be73cfa3f0..33575e65ef 100644 --- a/src/basic/cgroup-util.c +++ b/src/basic/cgroup-util.c @@ -2010,6 +2010,9 @@ int cg_unified_cached(bool flush) { unified_cache = CGROUP_UNIFIED_NONE; } } + } else if (F_TYPE_EQUAL(fs.f_type, SYSFS_MAGIC)) { + return log_debug_errno(SYNTHETIC_ERRNO(ENOMEDIUM), + "No filesystem is currently mounted on /sys/fs/cgroup."); } else return log_debug_errno(SYNTHETIC_ERRNO(ENOMEDIUM), "Unknown filesystem type %llx mounted on /sys/fs/cgroup.",