The writecache driver does not handle asynchronous pmem. Reject it when supplied as cache.
Link: https://lore.kernel.org/linux-nvdimm/87lfk5hahc....@linux.ibm.com/ Fixes: 6e84200c0a29 ("virtio-pmem: Add virtio pmem driver") Signed-off-by: Michal Suchanek <msucha...@suse.de> --- 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..57b0a972f6fd 100644 --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -2277,6 +2277,12 @@ static int writecache_ctr(struct dm_target *ti, unsigned argc, char **argv) wc->memory_map_size -= (uint64_t)wc->start_sector << SECTOR_SHIFT; + if (!dax_synchronous(wc->ssd_dev->dax_dev)) { + r = -EOPNOTSUPP; + ti->error = "Asynchronous persistent memory not supported as pmem cache"; + goto bad; + } + bio_list_init(&wc->flush_list); wc->flush_thread = kthread_create(writecache_flush_thread, wc, "dm_writecache_flush"); if (IS_ERR(wc->flush_thread)) { -- 2.26.2
