This is a note to let you know that I've just added the patch titled io_uring: dont remove file from msg_ring reqs to the 6.0-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: io_uring-dont-remove-file-from-msg_ring-reqs.patch and it can be found in the queue-6.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From ef0ec1ad03119b8b46b035dad42bca7d6da7c2e5 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov <asml.silence@xxxxxxxxx> Date: Wed, 7 Dec 2022 03:53:26 +0000 Subject: io_uring: dont remove file from msg_ring reqs From: Pavel Begunkov <asml.silence@xxxxxxxxx> commit ef0ec1ad03119b8b46b035dad42bca7d6da7c2e5 upstream. We should not be messing with req->file outside of core paths. Clearing it makes msg_ring non reentrant, i.e. luckily io_msg_send_fd() fails the request on failed io_double_lock_ctx() but clearly was originally intended to do retries instead. Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx> Link: https://lore.kernel.org/r/e5ac9edadb574fe33f6d727cb8f14ce68262a684.1670384893.git.asml.silence@xxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- io_uring/io_uring.c | 2 +- io_uring/msg_ring.c | 4 ---- io_uring/opdef.c | 7 +++++++ io_uring/opdef.h | 2 ++ 4 files changed, 10 insertions(+), 5 deletions(-) --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -1607,7 +1607,7 @@ static int io_issue_sqe(struct io_kiocb return ret; /* If the op doesn't have a file, we're not polling for it */ - if ((req->ctx->flags & IORING_SETUP_IOPOLL) && req->file) + if ((req->ctx->flags & IORING_SETUP_IOPOLL) && def->iopoll_queue) io_iopoll_req_issued(req, issue_flags); return 0; --- a/io_uring/msg_ring.c +++ b/io_uring/msg_ring.c @@ -169,9 +169,5 @@ done: if (ret < 0) req_set_fail(req); io_req_set_res(req, ret, 0); - /* put file to avoid an attempt to IOPOLL the req */ - if (!(req->flags & REQ_F_FIXED_FILE)) - io_put_file(req->file); - req->file = NULL; return IOU_OK; } --- a/io_uring/opdef.c +++ b/io_uring/opdef.c @@ -63,6 +63,7 @@ const struct io_op_def io_op_defs[] = { .audit_skip = 1, .ioprio = 1, .iopoll = 1, + .iopoll_queue = 1, .async_size = sizeof(struct io_async_rw), .name = "READV", .prep = io_prep_rw, @@ -80,6 +81,7 @@ const struct io_op_def io_op_defs[] = { .audit_skip = 1, .ioprio = 1, .iopoll = 1, + .iopoll_queue = 1, .async_size = sizeof(struct io_async_rw), .name = "WRITEV", .prep = io_prep_rw, @@ -103,6 +105,7 @@ const struct io_op_def io_op_defs[] = { .audit_skip = 1, .ioprio = 1, .iopoll = 1, + .iopoll_queue = 1, .async_size = sizeof(struct io_async_rw), .name = "READ_FIXED", .prep = io_prep_rw, @@ -118,6 +121,7 @@ const struct io_op_def io_op_defs[] = { .audit_skip = 1, .ioprio = 1, .iopoll = 1, + .iopoll_queue = 1, .async_size = sizeof(struct io_async_rw), .name = "WRITE_FIXED", .prep = io_prep_rw, @@ -275,6 +279,7 @@ const struct io_op_def io_op_defs[] = { .audit_skip = 1, .ioprio = 1, .iopoll = 1, + .iopoll_queue = 1, .async_size = sizeof(struct io_async_rw), .name = "READ", .prep = io_prep_rw, @@ -290,6 +295,7 @@ const struct io_op_def io_op_defs[] = { .audit_skip = 1, .ioprio = 1, .iopoll = 1, + .iopoll_queue = 1, .async_size = sizeof(struct io_async_rw), .name = "WRITE", .prep = io_prep_rw, @@ -475,6 +481,7 @@ const struct io_op_def io_op_defs[] = { .needs_file = 1, .plug = 1, .name = "URING_CMD", + .iopoll_queue = 1, .async_size = uring_cmd_pdu_size(1), .prep = io_uring_cmd_prep, .issue = io_uring_cmd, --- a/io_uring/opdef.h +++ b/io_uring/opdef.h @@ -25,6 +25,8 @@ struct io_op_def { unsigned ioprio : 1; /* supports iopoll */ unsigned iopoll : 1; + /* have to be put into the iopoll list */ + unsigned iopoll_queue : 1; /* opcode specific path will handle ->async_data allocation if needed */ unsigned manual_alloc : 1; /* size of async data needed, if any */ Patches currently in stable-queue which might be from asml.silence@xxxxxxxxx are queue-6.0/io_uring-dont-remove-file-from-msg_ring-reqs.patch