diff options
| author | Hannes Reinecke <hare@suse.de> | 2011-09-28 08:07:01 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-10-03 11:41:13 -0700 |
| commit | c2b387f0295ffaeb5e96f0d6f745fde507abd651 (patch) | |
| tree | 9d817f12f4ecfa480ac1cc3b471af31837b30c8c | |
| parent | f0e47138b26bd26d312aa63522a579acac5552c6 (diff) | |
block: Free queue resources at blk_release_queue()
commit 777eb1bf15b8532c396821774bf6451e563438f5 upstream.
A kernel crash is observed when a mounted ext3/ext4 filesystem is
physically removed. The problem is that blk_cleanup_queue() frees up
some resources eg by calling elevator_exit(), which are not checked for
in normal operation. So we should rather move these calls to the
destructor function blk_release_queue() as at that point all remaining
references are gone. However, in doing so we have to ensure that any
externally supplied queue_lock is disconnected as the driver might free
up the lock after the call of blk_cleanup_queue(),
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | block/blk-core.c | 13 | ||||
| -rw-r--r-- | block/blk-sysfs.c | 5 |
2 files changed, 11 insertions, 7 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 1d49e1c7c90..847d04ef9f1 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -348,9 +348,10 @@ void blk_put_queue(struct request_queue *q) EXPORT_SYMBOL(blk_put_queue); /* - * Note: If a driver supplied the queue lock, it should not zap that lock - * unexpectedly as some queue cleanup components like elevator_exit() and - * blk_throtl_exit() need queue lock. + * Note: If a driver supplied the queue lock, it is disconnected + * by this function. The actual state of the lock doesn't matter + * here as the request_queue isn't accessible after this point + * (QUEUE_FLAG_DEAD is set) and no other requests will be queued. */ void blk_cleanup_queue(struct request_queue *q) { @@ -367,10 +368,8 @@ void blk_cleanup_queue(struct request_queue *q) queue_flag_set_unlocked(QUEUE_FLAG_DEAD, q); mutex_unlock(&q->sysfs_lock); - if (q->elevator) - elevator_exit(q->elevator); - - blk_throtl_exit(q); + if (q->queue_lock != &q->__queue_lock) + q->queue_lock = &q->__queue_lock; blk_put_queue(q); } diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index d935bd859c8..45c56d86b82 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -472,6 +472,11 @@ static void blk_release_queue(struct kobject *kobj) blk_sync_queue(q); + if (q->elevator) + elevator_exit(q->elevator); + + blk_throtl_exit(q); + if (rl->rq_pool) mempool_destroy(rl->rq_pool); |