4.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Disseldorp <ddiss@xxxxxxx> commit 2224d879c7c0f85c14183ef82eb48bd875ceb599 upstream. As of 5a60e87603c4c533492c515b7f62578189b03c9c, RBD object request allocations are made via rbd_obj_request_create() with GFP_NOIO. However, subsequent OSD request allocations in rbd_osd_req_create*() use GFP_ATOMIC. With heavy page cache usage (e.g. OSDs running on same host as krbd client), rbd_osd_req_create() order-1 GFP_ATOMIC allocations have been observed to fail, where direct reclaim would have allowed GFP_NOIO allocations to succeed. Suggested-by: Vlastimil Babka <vbabka@xxxxxxx> Suggested-by: Neil Brown <neilb@xxxxxxxx> Signed-off-by: David Disseldorp <ddiss@xxxxxxx> Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/block/rbd.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1955,7 +1955,7 @@ static struct ceph_osd_request *rbd_osd_ osdc = &rbd_dev->rbd_client->client->osdc; osd_req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false, - GFP_ATOMIC); + GFP_NOIO); if (!osd_req) return NULL; /* ENOMEM */ @@ -2004,7 +2004,7 @@ rbd_osd_req_create_copyup(struct rbd_obj rbd_dev = img_request->rbd_dev; osdc = &rbd_dev->rbd_client->client->osdc; osd_req = ceph_osdc_alloc_request(osdc, snapc, num_osd_ops, - false, GFP_ATOMIC); + false, GFP_NOIO); if (!osd_req) return NULL; /* ENOMEM */ @@ -2506,7 +2506,7 @@ static int rbd_img_request_fill(struct r bio_chain_clone_range(&bio_list, &bio_offset, clone_size, - GFP_ATOMIC); + GFP_NOIO); if (!obj_request->bio_list) goto out_unwind; } else if (type == OBJ_REQUEST_PAGES) { -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html