nvme: fixup crash on failed discovery

When the initial discovery fails the subsystem hasn't been setup yet
in nvme_mpath_stop, and we can't dereference ctrl->subsys.

Fixes: 0d0b660f ("nvme: add ANA support")
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index c643872..5a95628 100644 (file)
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -22,7 +22,7 @@ MODULE_PARM_DESC(multipath,
 
 inline bool nvme_ctrl_use_ana(struct nvme_ctrl *ctrl)
 {
-       return multipath && (ctrl->subsys->cmic & (1 << 3));
+       return multipath && ctrl->subsys && (ctrl->subsys->cmic & (1 << 3));
 }
 
 /*