From a46624580376a3a0beb218d94cbc7f258696e29f Mon Sep 17 00:00:00 2001 From: Michal Suchanek Date: Tue, 30 Jun 2020 17:49:24 +0200 Subject: [PATCH] dm writecache: reject asynchronous pmem devices DM writecache does not handle asynchronous pmem. Reject it when supplied as cache. Link: https://lore.kernel.org/linux-nvdimm/87lfk5hahc.fsf@linux.ibm.com/ Fixes: 6e84200c0a29 ("virtio-pmem: Add virtio pmem driver") Signed-off-by: Michal Suchanek Acked-by: Mikulas Patocka Cc: stable@vger.kernel.org # 5.3+ Signed-off-by: Mike Snitzer --- drivers/md/dm-writecache.c | 6 ++++++ 1 file changed, 6 insertions(+) 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";