block: kmemleak: Track the page allocations for struct request
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.marinas@arm.com>
Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Tested-by: Bart Van Assche<bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index f2d67b4..2077f0d 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 @@
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 @@
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;