md: using GFP_NOIO to allocate bio for flush request

flush request is issued in transaction commit code path usually, so looks using
GFP_KERNEL to allocate memory for flush request bio falls into the classic deadlock issue. dm already gets it right.

Signed-off-by Shaohua Li <[email protected]>

---
 drivers/md/md.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux/drivers/md/md.c
===================================================================

drivers/md/md.c +1 -1

@@ -450,7 +450,7 @@ static void submit_flushes(struct work_s
 			atomic_inc(&rdev->nr_pending);
 			atomic_inc(&rdev->nr_pending);
 			rcu_read_unlock();
-			bi = bio_alloc_mddev(GFP_KERNEL, 0, mddev);
+			bi = bio_alloc_mddev(GFP_NOIO, 0, mddev);
 			bi->bi_end_io = md_end_flush;
 			bi->bi_private = rdev;
 			bi->bi_bdev = rdev->bdev;

Quoted 5 lines · Shaohua Li

flush request is issued in transaction commit code path usually, so looks using
GFP_KERNEL to allocate memory for flush request bio falls into the classic deadlock issue. dm already gets it right.

ping!

Quoted 8 lines · Shaohua Li

Quoted 5 lines · Shaohua Li

flush request is issued in transaction commit code path usually, so looks using
GFP_KERNEL to allocate memory for flush request bio falls into the classic deadlock issue. dm already gets it right.

ping!

This one should probably also be queued for -stable right?