[PATCH 4.10 77/81] nvme/core: Fix race kicking freed request_queue

Greg Kroah-Hartman
2017-04-06T08:49:59Z

From: Keith Busch <keith.busch@intel.com>

commit f33447b90e96076483525b21cc4e0a8977cdd07c upstream.

If a namespace has already been marked dead, we don't want to kick the
request_queue again since we may have just freed it from another thread.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/nvme/host/core.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -2034,9 +2034,9 @@ void nvme_kill_queues(struct nvme_ctrl *
* Revalidating a dead namespace sets capacity to 0. This will
* end buffered writers dirtying pages that can't be synced.
*/
- if (ns->disk && !test_and_set_bit(NVME_NS_DEAD, &ns->flags))
- revalidate_disk(ns->disk);
-
+ if (!ns->disk || test_and_set_bit(NVME_NS_DEAD, &ns->flags))
+ continue;
+ revalidate_disk(ns->disk);
blk_set_queue_dying(ns->queue);
blk_mq_abort_requeue_list(ns->queue);
blk_mq_start_stopped_hw_queues(ns->queue, true);