Commit 08937bcd authored by Hannes Reinecke's avatar Hannes Reinecke Committed by Christoph Hellwig
Browse files

nvme-multipath: sysfs links may not be created for devices 



When rapidly rescanning for new namespaces nvme_mpath_add_sysfs_link() may be
called for a block device not added to sysfs. But NVME_NS_SYSFS_ATTR_LINK
had already been set, so when checking this device a second time we will fail
to create the link.

Fix this by exchanging the order of the block device check and the
NVME_NS_SYSFS_ATTR_LINK bit check.

Fixes: 4dbd2b2e ("nvme-multipath: Add visibility for round-robin io-policy")
Signed-off-by: default avatarHannes Reinecke <hare@kernel.org>
Reviewed-by: default avatarSagi Grimberg <sagi@grimberg.me&gt;**>
Reviewed-by: default avatarNilay Shroff <nilay@linux.ibm.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 26d7fb4f

drivers/nvme/host/multipath.c

+7 −7
Original line number Diff line number Diff line
@@ -1050,6 +1050,13 @@ void nvme_mpath_add_sysfs_link(struct nvme_ns_head *head) 
	srcu_idx = srcu_read_lock(&head->srcu);



	list_for_each_entry_rcu(ns, &head->list, siblings) {

		/*

		 * Ensure that ns path disk node is already added otherwise we

		 * may get invalid kobj name for target

		 */

		if (!test_bit(GD_ADDED, &ns->disk->state))

			continue;



		/*

		 * Avoid creating link if it already exists for the given path.

		 * When path ana state transitions from optimized to non-
@@ -1065,13 +1072,6 @@ void nvme_mpath_add_sysfs_link(struct nvme_ns_head *head) 
		if (test_and_set_bit(NVME_NS_SYSFS_ATTR_LINK, &ns->flags))

			continue;



		/*

		 * Ensure that ns path disk node is already added otherwise we

		 * may get invalid kobj name for target

		 */

		if (!test_bit(GD_ADDED, &ns->disk->state))

			continue;



		target = disk_to_dev(ns->disk);

		/*

		 * Create sysfs link from head gendisk kobject @kobj to the