diff options
| author | Shaohua Li <shli@kernel.org> | 2014-04-15 09:12:54 +0800 |
|---|---|---|
| committer | NeilBrown <neilb@suse.de> | 2014-04-17 17:05:28 +1000 |
| commit | c7a6d35e463caacab08ca0333bdec5b8bdce8bbb (patch) | |
| tree | bf4abac968402f11ba3d26e238ab62173f2bb23a | |
| parent | e240c1839d11152b0355442f8ac6d2d2d921be36 (diff) | |
| download | linux-c7a6d35e463caacab08ca0333bdec5b8bdce8bbb.tar.bz2 | |
raid5: fix a race of stripe count check
I hit another BUG_ON with e240c1839d11152b0355442. In __get_priority_stripe(),
stripe count equals to 0 initially. Between atomic_inc and BUG_ON,
get_active_stripe() finds the stripe. So the stripe count isn't 1 any more.
V2: keeps the BUG_ON suggested by Neil.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
| -rw-r--r-- | drivers/md/raid5.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 25247a852912..ad1b9bea446e 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -4370,8 +4370,7 @@ static struct stripe_head *__get_priority_stripe(struct r5conf *conf, int group) sh->group = NULL; } list_del_init(&sh->lru); - atomic_inc(&sh->count); - BUG_ON(atomic_read(&sh->count) != 1); + BUG_ON(atomic_inc_return(&sh->count) != 1); return sh; } |