diff options
| author | Tejun Heo <tj@kernel.org> | 2015-07-09 16:39:48 -0400 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2015-07-09 14:41:08 -0600 |
| commit | 144232b34258c1fc19729e077c6fb161e30da07b (patch) | |
| tree | 8f048fd73d864a8f41917068d6e610fc5b0e0f0b /block/blk-flush.c | |
| parent | 838f13bf4b6737d4aec508558e45f81798fc2677 (diff) | |
blkcg: blkcg_css_alloc() should grab blkcg_pol_mutex while iterating blkcg_policy[]
An entry in blkcg_policy[] is stable while there are non-bypassing
in-flight IOs on a request_queue which has the policy activated. This
is why most derefs of blkcg_policy[] don't need explicit locking;
however, blkcg_css_alloc() isn't invoked from IO path and thus doesn't
have this protection and may race policies being added and removed.
Fix it by adding explicit blkcg_pol_mutex protection around
blkcg_policy[] iteration in blkcg_css_alloc().
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: e48453c386f3 ("block, cgroup: implement policy-specific per-blkcg data")
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block/blk-flush.c')
0 files changed, 0 insertions, 0 deletions