From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 10E2C1AAE17 for ; Mon, 12 May 2025 10:01:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747044100; cv=none; b=axZiTejx253ctZm1qarXgXjAGcrFyvuqvECBccxigYIIkZMdjKm7sbddjklJ06/u2tVckXHNZ4HOIHIQbiZ3iBYjSpsoaDuGvBo/s5GJZq9gsYAZNgG/A+Re4m7nrcGqdtOunTRBIIKd3YSMzfO9cSPRGKepGAiSxlj3nyd3XdU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747044100; c=relaxed/simple; bh=ztpojngx31mfz9MhrBCk4M3ax4EVYhNrVmRwzfScW50=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=n6HqOeL4XiF8NG3pB8m4lBX+Kq0kcudyMKGVF5RIRxULvznDBNi7XlFxydnDVMNmoJmHdYHRhXgEGd5dPHpa1oeWYk2QGHkX8Yqa/P9vydVAFJKd20vBEFNZXGUImw4jh8hQ598LqvTl2rvs0nY5rWc0k2Bg8kBnYFX8J8G5ju4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=I4dORnzO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="I4dORnzO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0D2E4C4CEE7; Mon, 12 May 2025 10:01:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1747044099; bh=ztpojngx31mfz9MhrBCk4M3ax4EVYhNrVmRwzfScW50=; h=Subject:To:Cc:From:Date:From; b=I4dORnzOWgjCPhvsxjMj8FqLjM/+odWqhRbhyD/DMgpHjEtF4sJL8xXMzenSH4rrV RzEDyJDCq2eAf/jerbEsaeqYWhvIy/bvuc4RanDMd9v3tx4PgL6ZBIEcR3KaAis9bj SnwO44ZOZKSTXv3CAqUNtVidJxGXsC67lyTR7h3E= Subject: FAILED: patch "[PATCH] io_uring: always arm linked timeouts prior to issue" failed to apply to 6.12-stable tree To: axboe@kernel.dk,chase@path.net Cc: From: Date: Mon, 12 May 2025 12:01:25 +0200 Message-ID: <2025051225-maximize-tingly-00b5@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.12-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y git checkout FETCH_HEAD git cherry-pick -x b53e523261bf058ea4a518b482222e7a277b186b # git commit -s git send-email --to '' --in-reply-to '2025051225-maximize-tingly-00b5@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b53e523261bf058ea4a518b482222e7a277b186b Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Sun, 4 May 2025 08:06:28 -0600 Subject: [PATCH] io_uring: always arm linked timeouts prior to issue There are a few spots where linked timeouts are armed, and not all of them adhere to the pre-arm, attempt issue, post-arm pattern. This can be problematic if the linked request returns that it will trigger a callback later, and does so before the linked timeout is fully armed. Consolidate all the linked timeout handling into __io_issue_sqe(), rather than have it spread throughout the various issue entry points. Cc: stable@vger.kernel.org Link: https://github.com/axboe/liburing/issues/1390 Reported-by: Chase Hiltz Signed-off-by: Jens Axboe diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index a2b256e96d5d..769814d71153 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -448,24 +448,6 @@ static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req) return req->link; } -static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req) -{ - if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT))) - return NULL; - return __io_prep_linked_timeout(req); -} - -static noinline void __io_arm_ltimeout(struct io_kiocb *req) -{ - io_queue_linked_timeout(__io_prep_linked_timeout(req)); -} - -static inline void io_arm_ltimeout(struct io_kiocb *req) -{ - if (unlikely(req->flags & REQ_F_ARM_LTIMEOUT)) - __io_arm_ltimeout(req); -} - static void io_prep_async_work(struct io_kiocb *req) { const struct io_issue_def *def = &io_issue_defs[req->opcode]; @@ -518,7 +500,6 @@ static void io_prep_async_link(struct io_kiocb *req) static void io_queue_iowq(struct io_kiocb *req) { - struct io_kiocb *link = io_prep_linked_timeout(req); struct io_uring_task *tctx = req->tctx; BUG_ON(!tctx); @@ -543,8 +524,6 @@ static void io_queue_iowq(struct io_kiocb *req) trace_io_uring_queue_async_work(req, io_wq_is_hashed(&req->work)); io_wq_enqueue(tctx->io_wq, &req->work); - if (link) - io_queue_linked_timeout(link); } static void io_req_queue_iowq_tw(struct io_kiocb *req, io_tw_token_t tw) @@ -1724,15 +1703,22 @@ static bool io_assign_file(struct io_kiocb *req, const struct io_issue_def *def, return !!req->file; } +#define REQ_ISSUE_SLOW_FLAGS (REQ_F_CREDS | REQ_F_ARM_LTIMEOUT) + static inline int __io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags, const struct io_issue_def *def) { const struct cred *creds = NULL; + struct io_kiocb *link = NULL; int ret; - if (unlikely((req->flags & REQ_F_CREDS) && req->creds != current_cred())) - creds = override_creds(req->creds); + if (unlikely(req->flags & REQ_ISSUE_SLOW_FLAGS)) { + if ((req->flags & REQ_F_CREDS) && req->creds != current_cred()) + creds = override_creds(req->creds); + if (req->flags & REQ_F_ARM_LTIMEOUT) + link = __io_prep_linked_timeout(req); + } if (!def->audit_skip) audit_uring_entry(req->opcode); @@ -1742,8 +1728,12 @@ static inline int __io_issue_sqe(struct io_kiocb *req, if (!def->audit_skip) audit_uring_exit(!ret, ret); - if (creds) - revert_creds(creds); + if (unlikely(creds || link)) { + if (creds) + revert_creds(creds); + if (link) + io_queue_linked_timeout(link); + } return ret; } @@ -1769,7 +1759,6 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) if (ret == IOU_ISSUE_SKIP_COMPLETE) { ret = 0; - io_arm_ltimeout(req); /* If the op doesn't have a file, we're not polling for it */ if ((req->ctx->flags & IORING_SETUP_IOPOLL) && def->iopoll_queue) @@ -1824,8 +1813,6 @@ void io_wq_submit_work(struct io_wq_work *work) else req_ref_get(req); - io_arm_ltimeout(req); - /* either cancelled or io-wq is dying, so don't touch tctx->iowq */ if (atomic_read(&work->flags) & IO_WQ_WORK_CANCEL) { fail: @@ -1941,15 +1928,11 @@ struct file *io_file_get_normal(struct io_kiocb *req, int fd) static void io_queue_async(struct io_kiocb *req, int ret) __must_hold(&req->ctx->uring_lock) { - struct io_kiocb *linked_timeout; - if (ret != -EAGAIN || (req->flags & REQ_F_NOWAIT)) { io_req_defer_failed(req, ret); return; } - linked_timeout = io_prep_linked_timeout(req); - switch (io_arm_poll_handler(req, 0)) { case IO_APOLL_READY: io_kbuf_recycle(req, 0); @@ -1962,9 +1945,6 @@ static void io_queue_async(struct io_kiocb *req, int ret) case IO_APOLL_OK: break; } - - if (linked_timeout) - io_queue_linked_timeout(linked_timeout); } static inline void io_queue_sqe(struct io_kiocb *req)