Patch "rbd: use GFP_NOIO for parent stat and data requests" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

rbd: use GFP_NOIO for parent stat and data requests

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
rbd-use-gfp_noio-for-parent-stat-and-data-requests.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Ilya Dryomov <[email protected]>
Date: Mon, 6 Nov 2017 11:33:36 +0100
Subject: rbd: use GFP_NOIO for parent stat and data requests

From: Ilya Dryomov <[email protected]>

commit 1e37f2f84680fa7f8394fd444b6928e334495ccc upstream.

rbd_img_obj_exists_submit() and rbd_img_obj_parent_read_full() are on the writeback path for cloned images -- we attempt a stat on the parent object to see if it exists and potentially read it in to call copyup. GFP_NOIO should be used instead of GFP_KERNEL here.

---
 drivers/block/rbd.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -2788,7 +2788,7 @@ static int rbd_img_obj_parent_read_full(
 	 * from the parent.
 	 */
 	page_count = (u32)calc_pages_for(0, length);
-	pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
+	pages = ceph_alloc_page_vector(page_count, GFP_NOIO);
 	if (IS_ERR(pages)) {
 		result = PTR_ERR(pages);
 		pages = NULL;

@@ -2922,7 +2922,7 @@ static int rbd_img_obj_exists_submit(str
 	 */
 	size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32);
 	page_count = (u32)calc_pages_for(0, size);
-	pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
+	pages = ceph_alloc_page_vector(page_count, GFP_NOIO);
 	if (IS_ERR(pages)) {
 		ret = PTR_ERR(pages);
 		goto fail_stat_request;

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/rbd-use-gfp_noio-for-parent-stat-and-data-requests.patch