diff options
| author | Hannes Reinecke <hare@suse.de> | 2021-07-16 13:30:35 +0200 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2021-07-21 09:55:40 +0200 |
| commit | 5396fdac56d87d04e75e5068c0c92d33625f51e7 (patch) | |
| tree | e408a4a51c5cb8346153afededaf514483374a46 /drivers/nvme/host/core.c | |
| parent | 7764656b108cd308c39e9a8554353b8f9ca232a3 (diff) | |
nvme: fix refcounting imbalance when all paths are down
When the last path to a ns_head drops the current code
removes the ns_head from the subsystem list, but will only
delete the disk itself if the last reference to the ns_head
drops. This is causing an refcounting imbalance eg when
applications have a reference to the disk, as then they'll
never get notified that the disk is in fact dead.
This patch moves the call 'del_gendisk' into nvme_mpath_check_last_path(),
ensuring that the disk can be properly removed and applications get the
appropriate notifications.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'drivers/nvme/host/core.c')
| -rw-r--r-- | drivers/nvme/host/core.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 11779be42186..17c05a4595f0 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -3807,6 +3807,8 @@ static void nvme_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid, static void nvme_ns_remove(struct nvme_ns *ns) { + bool last_path = false; + if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags)) return; @@ -3815,8 +3817,6 @@ static void nvme_ns_remove(struct nvme_ns *ns) mutex_lock(&ns->ctrl->subsys->lock); list_del_rcu(&ns->siblings); - if (list_empty(&ns->head->list)) - list_del_init(&ns->head->entry); mutex_unlock(&ns->ctrl->subsys->lock); synchronize_rcu(); /* guarantee not available in head->list */ @@ -3836,7 +3836,15 @@ static void nvme_ns_remove(struct nvme_ns *ns) list_del_init(&ns->list); up_write(&ns->ctrl->namespaces_rwsem); - nvme_mpath_check_last_path(ns); + /* Synchronize with nvme_init_ns_head() */ + mutex_lock(&ns->head->subsys->lock); + if (list_empty(&ns->head->list)) { + list_del_init(&ns->head->entry); + last_path = true; + } + mutex_unlock(&ns->head->subsys->lock); + if (last_path) + nvme_mpath_shutdown_disk(ns->head); nvme_put_ns(ns); } |