Commits
Mike Snitzer committed d132cc6d9e9
dm cache: prevent corruption caused by discard_block_size > cache_block_size If the discard block size is larger than the cache block size we will not properly quiesce IO to a region that is about to be discarded. This results in a race between a cache migration where no copy is needed, and a write to an adjacent cache block that's within the same large discard block. Workaround this by limiting the discard_block_size to cache_block_size. Also limit the max_discard_sectors to cache_block_size. A more comprehensive fix that introduces range locking support in the bio_prison and proper quiescing of a discard range that spans multiple cache blocks is already in development. Reported-by: Morgan Mears <Morgan.Mears@netapp.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com> Acked-by: Heinz Mauelshagen <heinzm@redhat.com> Cc: stable@vger.kernel.org