The pages allocated for struct request contain pointers to other slab allocations (via ops->init_request). Since kmemleak does not track/scan page allocations, the slab objects will be reported as leaks (false positives). This patch adds kmemleak callbacks to allow tracking of such pages.
Signed-off-by: Catalin Marinas <catalin.mari...@arm.com> Reported-by: Bart Van Assche <bart.vanass...@sandisk.com> Tested-by: Bart Van Assche<bart.vanass...@sandisk.com> Cc: Christoph Hellwig <h...@infradead.org> Cc: Jens Axboe <ax...@kernel.dk> --- Jens, I just realised that no-one has picked this patch up for -rc1. It was discussed here previously: http://lkml.kernel.org/r/20150803104309.gb4...@e104818-lin.cambridge.arm.com Since it touches the block layer, are you fine with merging it? Thanks, Catalin block/blk-mq.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/block/blk-mq.c b/block/blk-mq.c index f2d67b4047a0..2077f0d2f95f 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -9,6 +9,7 @@ #include <linux/backing-dev.h> #include <linux/bio.h> #include <linux/blkdev.h> +#include <linux/kmemleak.h> #include <linux/mm.h> #include <linux/init.h> #include <linux/slab.h> @@ -1438,6 +1439,11 @@ static void blk_mq_free_rq_map(struct blk_mq_tag_set *set, while (!list_empty(&tags->page_list)) { page = list_first_entry(&tags->page_list, struct page, lru); list_del_init(&page->lru); + /* + * Remove kmemleak object previously allocated in + * blk_mq_init_rq_map(). + */ + kmemleak_free(page_address(page)); __free_pages(page, page->private); } @@ -1510,6 +1516,11 @@ static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, list_add_tail(&page->lru, &tags->page_list); p = page_address(page); + /* + * Allow kmemleak to scan these pages as they contain pointers + * to additional allocations like via ops->init_request(). + */ + kmemleak_alloc(p, order_to_size(this_order), 1, GFP_KERNEL); entries_per_page = order_to_size(this_order) / rq_size; to_do = min(entries_per_page, set->queue_depth - i); left -= to_do * rq_size; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/