When completing an overwrite bio ,in overwrite_endio(), the associated migration should not be added to the 'completed_migrations' until the bio's fields are restored with dm_unhook_bio(). Otherwise, do_worker() can race to process 'completed_migrations' before dm_unhook_bio() -- so the bio's bi_end_io is incorrect. This is unlikely to cause any problems given the current code but should be fixed on the basis of correctness. Also, the cache's spinlock only needs to be held when manipulating the 'completed_migrations' list -- other changes don't need protection. Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> Acked-by: Joe Thornber <ejt@xxxxxxxxxx> --- drivers/md/dm-cache-target.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index cd24a05..ed4cffe 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -1002,13 +1002,15 @@ static void overwrite_endio(struct bio *bio, int err) struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); unsigned long flags; + dm_unhook_bio(&pb->hook_info, bio); + if (err) mg->err = true; + mg->requeue_holder = false; + spin_lock_irqsave(&cache->lock, flags); list_add_tail(&mg->list, &cache->completed_migrations); - dm_unhook_bio(&pb->hook_info, bio); - mg->requeue_holder = false; spin_unlock_irqrestore(&cache->lock, flags); wake_worker(cache); -- 1.8.1.4 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel