Commit 0670e08bdfc67272f8c3087030417465629b8073
Committed by
Linus Torvalds
1 parent
099fca3225
Exists in
master
and in
4 other branches
cgroups: don't change release_agent when remount failed
Remount can fail in either case: - wrong mount options is specified, or option 'noprefix' is changed. - a to-be-added subsys is already mounted/active. When using remount to change 'release_agent', for the above former failure case, remount will return errno with release_agent unchanged, but for the latter case, remount will return EBUSY with relase_agent changed, which is unexpected I think: # mount -t cgroup -o cpu xxx /cgrp1 # mount -t cgroup -o cpuset,release_agent=agent1 yyy /cgrp2 # cat /cgrp2/release_agent agent1 # mount -t cgroup -o remount,cpuset,noprefix,release_agent=agent2 yyy /cgrp2 mount: /cgrp2 not mounted already, or bad option # cat /cgrp2/release_agent agent1 <-- ok # mount -t cgroup -o remount,cpu,cpuset,release_agent=agent2 yyy /cgrp2 mount: /cgrp2 is busy # cat /cgrp2/release_agent agent2 <-- unexpected! Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Paul Menage <menage@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing 1 changed file with 3 additions and 2 deletions Side-by-side Diff
kernel/cgroup.c
... | ... | @@ -915,10 +915,11 @@ |
915 | 915 | } |
916 | 916 | |
917 | 917 | ret = rebind_subsystems(root, opts.subsys_bits); |
918 | + if (ret) | |
919 | + goto out_unlock; | |
918 | 920 | |
919 | 921 | /* (re)populate subsystem files */ |
920 | - if (!ret) | |
921 | - cgroup_populate_dir(cgrp); | |
922 | + cgroup_populate_dir(cgrp); | |
922 | 923 | |
923 | 924 | if (opts.release_agent) |
924 | 925 | strcpy(root->release_agent_path, opts.release_agent); |