diff options
| author |   Joe Thornber <ejt@redhat.com> | 2014-04-08 11:08:41 +0100 |
|---|---|---|
| committer |   Mike Snitzer <snitzer@redhat.com> | 2014-04-08 10:10:51 -0400 |
| commit | 5e3283e2920a0bd8a806964d80274b8756e0dd7f (patch) | |
| tree | 3472cec2ea93f35e013a1c1997b231e16c32f264 /drivers/md | |
| parent | dm cache: fix a lock-inversion (diff) | |
| download | linux-dev-5e3283e2920a0bd8a806964d80274b8756e0dd7f.tar.xz linux-dev-5e3283e2920a0bd8a806964d80274b8756e0dd7f.zip | |
dm thin: irqsave must always be used with the pool->lock spinlock
Commit c140e1c4e23 ("dm thin: use per thin device deferred bio lists")
incorrectly stopped disabling irqs when taking the pool's spinlock.
Irqs must be disabled when taking the pool's spinlock otherwise a thread
could spin_lock(), then get interrupted to service thin_endio() in
interrupt context, which would then deadlock in spin_lock_irqsave().
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 | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index 53728be84dee..ae5fd0b9c75c 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -3101,6 +3101,7 @@ static int thin_ctr(struct dm_target *ti, unsigned argc, char **argv) struct thin_c *tc; struct dm_dev *pool_dev, *origin_dev; struct mapped_device *pool_md; + unsigned long flags; mutex_lock(&dm_thin_pool_table.mutex); @@ -3191,9 +3192,9 @@ static int thin_ctr(struct dm_target *ti, unsigned argc, char **argv) mutex_unlock(&dm_thin_pool_table.mutex); - spin_lock(&tc->pool->lock); + spin_lock_irqsave(&tc->pool->lock, flags); list_add_tail_rcu(&tc->list, &tc->pool->active_thins); - spin_unlock(&tc->pool->lock); + spin_unlock_irqrestore(&tc->pool->lock, flags); /* * This synchronize_rcu() call is needed here otherwise we risk a * wake_worker() call finding no bios to process (because the newly |