This is a note to let you know that I've just added the patch titled block/rnbd: replace REQ_OP_FLUSH with REQ_OP_WRITE to the 6.3-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: block-rnbd-replace-req_op_flush-with-req_op_write.patch and it can be found in the queue-6.3 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b4b4b59441c432247ad384f7a74113235572b1e3 Author: Guoqing Jiang <guoqing.jiang@xxxxxxxxx> Date: Fri May 12 11:46:31 2023 +0800 block/rnbd: replace REQ_OP_FLUSH with REQ_OP_WRITE [ Upstream commit 5e6e08087a4acb4ee3574cea32dbff0f63c7f608 ] Since flush bios are implemented as writes with no data and the preflush flag per Christoph's comment [1]. And we need to change it in rnbd accordingly. Otherwise, I got splatting when create fs from rnbd client. [ 464.028545] ------------[ cut here ]------------ [ 464.028553] WARNING: CPU: 0 PID: 65 at block/blk-core.c:751 submit_bio_noacct+0x32c/0x5d0 [ ... ] [ 464.028668] CPU: 0 PID: 65 Comm: kworker/0:1H Tainted: G OE 6.4.0-rc1 #9 [ 464.028671] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014 [ 464.028673] Workqueue: ib-comp-wq ib_cq_poll_work [ib_core] [ 464.028717] RIP: 0010:submit_bio_noacct+0x32c/0x5d0 [ 464.028720] Code: 03 0f 85 51 fe ff ff 48 8b 43 18 8b 88 04 03 00 00 85 c9 0f 85 3f fe ff ff e9 be fd ff ff 0f b6 d0 3c 0d 74 26 83 fa 01 74 21 <0f> 0b b8 0a 00 00 00 e9 56 fd ff ff 4c 89 e7 e8 70 a1 03 00 84 c0 [ 464.028722] RSP: 0018:ffffaf3680b57c68 EFLAGS: 00010202 [ 464.028724] RAX: 0000000000060802 RBX: ffffa09dcc18bf00 RCX: 0000000000000000 [ 464.028726] RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffffa09dde081d00 [ 464.028727] RBP: ffffaf3680b57c98 R08: ffffa09dde081d00 R09: ffffa09e38327200 [ 464.028729] R10: 0000000000000000 R11: 0000000000000000 R12: ffffa09dde081d00 [ 464.028730] R13: ffffa09dcb06e1e8 R14: 0000000000000000 R15: 0000000000200000 [ 464.028733] FS: 0000000000000000(0000) GS:ffffa09e3bc00000(0000) knlGS:0000000000000000 [ 464.028735] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 464.028736] CR2: 000055a4e8206c40 CR3: 0000000119f06000 CR4: 00000000003506f0 [ 464.028738] Call Trace: [ 464.028740] <TASK> [ 464.028746] submit_bio+0x1b/0x80 [ 464.028748] rnbd_srv_rdma_ev+0x50d/0x10c0 [rnbd_server] [ 464.028754] ? percpu_ref_get_many.constprop.0+0x55/0x140 [rtrs_server] [ 464.028760] ? __this_cpu_preempt_check+0x13/0x20 [ 464.028769] process_io_req+0x1dc/0x450 [rtrs_server] [ 464.028775] rtrs_srv_inv_rkey_done+0x67/0xb0 [rtrs_server] [ 464.028780] __ib_process_cq+0xbc/0x1f0 [ib_core] [ 464.028793] ib_cq_poll_work+0x2b/0xa0 [ib_core] [ 464.028804] process_one_work+0x2a9/0x580 [1]. https://lore.kernel.org/all/ZFHgefWofVt24tRl@xxxxxxxxxxxxx/ Signed-off-by: Guoqing Jiang <guoqing.jiang@xxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Chaitanya Kulkarni <kch@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230512034631.28686-1-guoqing.jiang@xxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/block/rnbd/rnbd-proto.h b/drivers/block/rnbd/rnbd-proto.h index ea7ac8bca63cf..da1d0542d7e2c 100644 --- a/drivers/block/rnbd/rnbd-proto.h +++ b/drivers/block/rnbd/rnbd-proto.h @@ -241,7 +241,7 @@ static inline blk_opf_t rnbd_to_bio_flags(u32 rnbd_opf) bio_opf = REQ_OP_WRITE; break; case RNBD_OP_FLUSH: - bio_opf = REQ_OP_FLUSH | REQ_PREFLUSH; + bio_opf = REQ_OP_WRITE | REQ_PREFLUSH; break; case RNBD_OP_DISCARD: bio_opf = REQ_OP_DISCARD;