diff options
| author | Joe Thornber <ejt@redhat.com> | 2014-03-03 15:46:42 +0000 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2014-03-05 15:26:58 -0500 |
| commit | 18adc57779866ba451237dccca2ebf019be2fa20 (patch) | |
| tree | a0f3a9d473fd433b7ffd5a7160ee55ad6d2ffd62 /drivers/md | |
| parent | 3e1a0699095803e53072699a4a1485af7744601d (diff) | |
| download | linux-18adc57779866ba451237dccca2ebf019be2fa20.tar.bz2 | |
dm thin: fix deadlock in __requeue_bio_list
The spin lock in requeue_io() was held for too long, allowing deadlock.
Don't worry, due to other issues addressed in the following "dm thin:
fix noflush suspend IO queueing" commit, this code was never called.
Fix this by taking the spin lock for a much shorter period of time.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-thin.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index 38a063f7afa4..f39876dd307d 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -369,14 +369,18 @@ struct dm_thin_endio_hook { struct dm_thin_new_mapping *overwrite_mapping; }; -static void __requeue_bio_list(struct thin_c *tc, struct bio_list *master) +static void requeue_bio_list(struct thin_c *tc, struct bio_list *master) { struct bio *bio; struct bio_list bios; + unsigned long flags; bio_list_init(&bios); + + spin_lock_irqsave(&tc->pool->lock, flags); bio_list_merge(&bios, master); bio_list_init(master); + spin_unlock_irqrestore(&tc->pool->lock, flags); while ((bio = bio_list_pop(&bios))) { struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook)); @@ -391,12 +395,9 @@ static void __requeue_bio_list(struct thin_c *tc, struct bio_list *master) static void requeue_io(struct thin_c *tc) { struct pool *pool = tc->pool; - unsigned long flags; - spin_lock_irqsave(&pool->lock, flags); - __requeue_bio_list(tc, &pool->deferred_bios); - __requeue_bio_list(tc, &pool->retry_on_resume_list); - spin_unlock_irqrestore(&pool->lock, flags); + requeue_bio_list(tc, &pool->deferred_bios); + requeue_bio_list(tc, &pool->retry_on_resume_list); } static void error_retry_list(struct pool *pool) |