From: Nikos Tsironis ntsironis@arrikto.com
commit cca2c6aebe86f68103a8615074b3578e854b5016 upstream.
Metadata resize shouldn't happen in the ctr. The ctr loads a temporary (inactive) table that will only become active upon resume. That is why resize should always be done in terms of resume. Otherwise a load (ctr) whose inactive table never becomes active will incorrectly resize the metadata.
Also, perform the resize directly in preresume, instead of using the worker to do it.
The worker might run other metadata operations, e.g., it could start digestion, before resizing the metadata. These operations will end up using the old size.
This could lead to errors, like:
device-mapper: era: metadata_digest_transcribe_writeset: dm_array_set_value failed device-mapper: era: process_old_eras: digest step failed, stopping digestion
The reason of the above error is that the worker started the digestion of the archived writeset using the old, larger size.
As a result, metadata_digest_transcribe_writeset tried to write beyond the end of the era array.
Fixes: eec40579d84873 ("dm: add era target") Cc: stable@vger.kernel.org # v3.15+ Signed-off-by: Nikos Tsironis ntsironis@arrikto.com Signed-off-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/md/dm-era-target.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-)
--- a/drivers/md/dm-era-target.c +++ b/drivers/md/dm-era-target.c @@ -1501,15 +1501,6 @@ static int era_ctr(struct dm_target *ti, } era->md = md;
- era->nr_blocks = calc_nr_blocks(era); - - r = metadata_resize(era->md, &era->nr_blocks); - if (r) { - ti->error = "couldn't resize metadata"; - era_destroy(era); - return -ENOMEM; - } - era->wq = alloc_ordered_workqueue("dm-" DM_MSG_PREFIX, WQ_MEM_RECLAIM); if (!era->wq) { ti->error = "could not create workqueue for metadata object"; @@ -1584,9 +1575,17 @@ static int era_preresume(struct dm_targe dm_block_t new_size = calc_nr_blocks(era);
if (era->nr_blocks != new_size) { - r = in_worker1(era, metadata_resize, &new_size); - if (r) + r = metadata_resize(era->md, &new_size); + if (r) { + DMERR("%s: metadata_resize failed", __func__); + return r; + } + + r = metadata_commit(era->md); + if (r) { + DMERR("%s: metadata_commit failed", __func__); return r; + }
era->nr_blocks = new_size; }