diff options
| author | Mike Snitzer <snitzer@redhat.com> | 2017-06-21 02:14:30 +0300 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2017-06-21 19:04:50 +0300 |
| commit | feb7695fe9fb83084aa29de0094774f4c9d4c9fc (patch) | |
| tree | dbdc175a3abd214ec6cef8531d07944407610421 | |
| parent | 7def52b78a5fda14864aab9b6fd14f09a4d4ff72 (diff) | |
| download | linux-feb7695fe9fb83084aa29de0094774f4c9d4c9fc.tar.xz | |
dm io: fix duplicate bio completion due to missing ref count
If only a subset of the devices associated with multiple regions support
a given special operation (eg. DISCARD) then the dec_count() that is
used to set error for the region must increment the io->count.
Otherwise, when the dec_count() is called it can cause the dm-io
caller's bio to be completed multiple times. As was reported against
the dm-mirror target that had mirror legs with a mix of discard
capabilities.
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=196077
Reported-by: Zhang Yi <yizhan@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| -rw-r--r-- | drivers/md/dm-io.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c index 3702e502466d..8d5ca30f6551 100644 --- a/drivers/md/dm-io.c +++ b/drivers/md/dm-io.c @@ -317,8 +317,8 @@ static void do_region(int op, int op_flags, unsigned region, else if (op == REQ_OP_WRITE_SAME) special_cmd_max_sectors = q->limits.max_write_same_sectors; if ((op == REQ_OP_DISCARD || op == REQ_OP_WRITE_ZEROES || - op == REQ_OP_WRITE_SAME) && - special_cmd_max_sectors == 0) { + op == REQ_OP_WRITE_SAME) && special_cmd_max_sectors == 0) { + atomic_inc(&io->count); dec_count(io, region, -EOPNOTSUPP); return; } |