dm block manager: reinstate message when validator fails

Reinstate a useful error message when the block manager buffer validator fails.
This was mistakenly eliminated when the block manager was converted to use
dm-bufio.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/md/persistent-data/dm-block-manager.c b/drivers/md/persistent-data/dm-block-manager.c
index 5ba277768d9..47b683e67a7 100644
--- a/drivers/md/persistent-data/dm-block-manager.c
+++ b/drivers/md/persistent-data/dm-block-manager.c
@@ -428,8 +428,11 @@ static int dm_bm_validate_buffer(struct dm_block_manager *bm,
                 if (!v)
                         return 0;
                 r = v->check(v, (struct dm_block *) buf, dm_bufio_get_block_size(bm->bufio));
-                if (unlikely(r))
+                if (unlikely(r)) {
+                        DMERR("%s validator check failed for block %llu", v->name,
+                              (unsigned long long) dm_bufio_get_block_number(buf));
                         return r;
+                }
                 aux->validator = v;
         } else {
                 if (unlikely(aux->validator != v)) {