Merge tag 'for-5.8/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - A request-based DM fix to not use a waitqueue to wait for blk-mq IO
   completion because doing so is racey.

 - A couple more DM zoned target fixes to address issues introduced
   during the 5.8 cycle.

 - A DM core fix to use proper interface to cleanup DM's static flush
   bio.

 - A DM core fix to prevent mm recursion during memory allocation needed
   by dm_kobject_uevent.

* tag 'for-5.8/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm: use noio when sending kobject event
  dm zoned: Fix zone reclaim trigger
  dm zoned: fix unused but set variable warnings
  dm writecache: reject asynchronous pmem devices
  dm: use bio_uninit instead of bio_disassociate_blkg
  dm: do not use waitqueue for request-based DM

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 30505d70f423..5358894bb9fd 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -2266,6 +2266,12 @@ invalid_optional:
 	}
 
 	if (WC_MODE_PMEM(wc)) {
+		if (!dax_synchronous(wc->ssd_dev->dax_dev)) {
+			r = -EOPNOTSUPP;
+			ti->error = "Asynchronous persistent memory not supported as pmem cache";
+			goto bad;
+		}
+
 		r = persistent_memory_claim(wc);
 		if (r) {
 			ti->error = "Unable to map persistent memory for cache";