kernel/linux.git/io_uring/poll.c, branch v6.1.168

io_uring/cancel: support opcode based lookup and cancelation

2026-03-04T12:20:02+00:00

[ Upstream commit d7b8b079a8f6bc007d06d9ee468659dae6053e13 ] Add IORING_ASYNC_CANCEL_OP flag for cancelation, which allows the application to target cancelation based on the opcode of the original request. Signed-off-by: Jens Axboe Stable-dep-of: 22dbb0987bd1 ("io_uring/cancel: de-unionize file and user_data in struct io_cancel_data") Signed-off-by: Sasha Levin

io_uring/poll: correctly handle io_poll_add() return value on update

2026-01-11T14:18:56+00:00

Commit 84230ad2d2afbf0c44c32967e525c0ad92e26b4e upstream. When the core of io_uring was updated to handle completions consistently and with fixed return codes, the POLL_REMOVE opcode with updates got slightly broken. If a POLL_ADD is pending and then POLL_REMOVE is used to update the events of that request, if that update causes the POLL_ADD to now trigger, then that completion is lost and a CQE is never posted. Additionally, ensure that if an update does cause an existing POLL_ADD to complete, that the completion value isn't always overwritten with -ECANCELED. For that case, whatever io_poll_add() set the value to should just be retained. Cc: stable@vger.kernel.org Fixes: 97b388d70b53 ("io_uring: handle completions in the core") Reported-by: syzbot+641eec6b7af1f62f2b99@syzkaller.appspotmail.com Tested-by: syzbot+641eec6b7af1f62f2b99@syzkaller.appspotmail.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

io_uring: include dying ring in task_work "should cancel" state

2025-09-25T08:58:53+00:00

Commit 3539b1467e94336d5854ebf976d9627bfb65d6c3 upstream. When running task_work for an exiting task, rather than perform the issue retry attempt, the task_work is canceled. However, this isn't done for a ring that has been closed. This can lead to requests being successfully completed post the ring being closed, which is somewhat confusing and surprising to an application. Rather than just check the task exit state, also include the ring ref state in deciding whether or not to terminate a given request when run from task_work. Cc: stable@vger.kernel.org # 6.1+ Link: https://github.com/axboe/liburing/discussions/1459 Reported-by: Benedek Thaler Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

io_uring: backport io_should_terminate_tw()

2025-09-25T08:58:53+00:00

Parts of commit b6f58a3f4aa8dba424356c7a69388a81f4459300 upstream. Backport io_should_terminate_tw() helper to judge whether task_work should be run or terminated. Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

io_uring/poll: fix POLLERR handling

2025-07-24T06:51:48+00:00

commit c7cafd5b81cc07fb402e3068d134c21e60ea688c upstream. 8c8492ca64e7 ("io_uring/net: don't retry connect operation on EPOLLERR") is a little dirty hack that 1) wrongfully assumes that POLLERR equals to a failed request, which breaks all POLLERR users, e.g. all error queue recv interfaces. 2) deviates the connection request behaviour from connect(2), and 3) racy and solved at a wrong level. Nothing can be done with 2) now, and 3) is beyond the scope of the patch. At least solve 1) by moving the hack out of generic poll handling into io_connect(). Cc: stable@vger.kernel.org Fixes: 8c8492ca64e79 ("io_uring/net: don't retry connect operation on EPOLLERR") Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/3dc89036388d602ebd84c28e5042e457bdfc952b.1752682444.git.asml.silence@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

io_uring: fix multishots with selected buffers

2025-02-21T12:49:53+00:00

[ upstream commit d63b0e8a628e62ca85a0f7915230186bb92f8bb4 ] We do io_kbuf_recycle() when arming a poll but every iteration of a multishot can grab more buffers, which is why we need to flush the kbuf ring state before continuing with waiting. Cc: stable@vger.kernel.org Fixes: b3fdea6ecb55c ("io_uring: multishot recv") Reported-by: Muhammad Ramdhan Reported-by: Bing-Jhong Billy Jheng Reported-by: Jacob Soo Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/1bfc9990fe435f1fc6152ca9efeba5eb3e68339c.1738025570.git.asml.silence@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

io_uring/net: don't retry connect operation on EPOLLERR

2025-02-21T12:49:50+00:00

commit 8c8492ca64e79c6e0f433e8c9d2bcbd039ef83d0 upstream. If a socket is shutdown before the connection completes, POLLERR is set in the poll mask. However, connect ignores this as it doesn't know, and attempts the connection again. This may lead to a bogus -ETIMEDOUT result, where it should have noticed the POLLERR and just returned -ECONNRESET instead. Have the poll logic check for whether or not POLLERR is set in the mask, and if so, mark the request as failed. Then connect can appropriately fail the request rather than retry it. Reported-by: Sergey Galas Cc: stable@vger.kernel.org Link: https://github.com/axboe/liburing/discussions/1335 Fixes: 3fb1bd688172 ("io_uring/net: handle -EINPROGRESS correct for IORING_OP_CONNECT") Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

io_uring: always lock in io_apoll_task_func

2023-09-19T10:27:54+00:00

From: Dylan Yudaken [ upstream commit c06c6c5d276707e04cedbcc55625e984922118aa ] This is required for the failure case (io_req_complete_failed) and is missing. The alternative would be to only lock in the failure path, however all of the non-error paths in io_poll_check_events that do not do not return IOU_POLL_NO_ACTION end up locking anyway. The only extraneous lock would be for the multishot poll overflowing the CQE ring, however multishot poll would probably benefit from being locked as it will allow completions to be batched. So it seems reasonable to lock always. Signed-off-by: Dylan Yudaken Link: https://lore.kernel.org/r/20221124093559.3780686-3-dylany@meta.com Signed-off-by: Jens Axboe Signed-off-by: Pavel Begunkov Signed-off-by: Greg Kroah-Hartman

io_uring/poll: serialize poll linked timer start with poll removal

2023-06-28T09:12:27+00:00

Commit ef7dfac51d8ed961b742218f526bd589f3900a59 upstream. We selectively grab the ctx->uring_lock for poll update/removal, but we really should grab it from the start to fully synchronize with linked timeouts. Normally this is indeed the case, but if requests are forced async by the application, we don't fully cover removal and timer disarm within the uring_lock. Make this simpler by having consistent locking state for poll removal. Cc: stable@vger.kernel.org # 6.1+ Reported-by: Querijn Voet Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

io_uring/poll: clear single/double poll flags on poll arming

2023-04-06T10:10:51+00:00

commit 005308f7bdacf5685ed1a431244a183dbbb9e0e8 upstream. Unless we have at least one entry queued, then don't call into io_poll_remove_entries(). Normally this isn't possible, but if we retry poll then we can have ->nr_entries cleared again as we're setting it up. If this happens for a poll retry, then we'll still have at least REQ_F_SINGLE_POLL set. io_poll_remove_entries() then thinks it has entries to remove. Clear REQ_F_SINGLE_POLL and REQ_F_DOUBLE_POLL unconditionally when arming a poll request. Fixes: c16bda37594f ("io_uring/poll: allow some retries for poll triggering spuriously") Cc: stable@vger.kernel.org Reported-by: Pengfei Xu Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman