path: root/drivers/md
diff options
authorMikulas Patocka <>2021-05-25 13:16:21 -0400
committerMike Snitzer <>2021-05-25 16:16:47 -0400
commitf16dba5dc6f094041ab8c356e1e3a48ee0e3c8cd (patch)
treed23c77eb0d30a6419382061a3ccfb4491ae7ef1e /drivers/md
parent0c1f3193b1cdd21e7182f97dc9bca7d284d18a15 (diff)
dm snapshot: revert "fix a crash when an origin has no snapshots"
Commit 7ee06ddc4038f936b0d4459d37a7d4d844fb03db ("dm snapshot: fix a crash when an origin has no snapshots") introduced a regression in snapshot merging - causing the lvm2 test got stuck in an infinite loop. Even though commit 7ee06ddc4038f936b0d4459d37a7d4d844fb03db was marked for stable@ the stable team was notified to _not_ backport it. Fixes: 7ee06ddc4038 ("dm snapshot: fix a crash when an origin has no snapshots") Signed-off-by: Mikulas Patocka <> Signed-off-by: Mike Snitzer <>
Diffstat (limited to 'drivers/md')
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index b8e4d31124ea..75e59294ef77 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -855,11 +855,12 @@ static int dm_add_exception(void *context, chunk_t old, chunk_t new)
static uint32_t __minimum_chunk_size(struct origin *o)
struct dm_snapshot *snap;
- unsigned chunk_size = rounddown_pow_of_two(UINT_MAX);
+ unsigned chunk_size = 0;
if (o)
list_for_each_entry(snap, &o->snapshots, list)
- chunk_size = min(chunk_size, snap->store->chunk_size);
+ chunk_size = min_not_zero(chunk_size,
+ snap->store->chunk_size);
return (uint32_t) chunk_size;