From: Mike Snitzer Fix a significant memory leak inadvertently introduced during simplification of cell_release_singleton() in commit 6f94a4c45a6f744383f9f695dde019998db3df55 ("dm thin: fix stacked bi_next usage"). A cell's hlist_del() must be accompanied by a mempool_free(). Use __cell_release() to do this, like before. Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon --- drivers/md/dm-thin.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) Index: linux-3.4-rc6/drivers/md/dm-thin.c =================================================================== --- linux-3.4-rc6.orig/drivers/md/dm-thin.c +++ linux-3.4-rc6/drivers/md/dm-thin.c @@ -279,8 +279,10 @@ static void __cell_release(struct cell * hlist_del(&cell->list); - bio_list_add(inmates, cell->holder); - bio_list_merge(inmates, &cell->bios); + if (inmates) { + bio_list_add(inmates, cell->holder); + bio_list_merge(inmates, &cell->bios); + } mempool_free(cell, prison->cell_pool); } @@ -303,9 +305,10 @@ static void cell_release(struct cell *ce */ static void __cell_release_singleton(struct cell *cell, struct bio *bio) { - hlist_del(&cell->list); BUG_ON(cell->holder != bio); BUG_ON(!bio_list_empty(&cell->bios)); + + __cell_release(cell, NULL); } static void cell_release_singleton(struct cell *cell, struct bio *bio)