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 428DD2D9EC2 for ; Mon, 29 Dec 2025 12:21:29 +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=1767010889; cv=none; b=iEE8yKmPzjlMjqhGHo16mtSrmtnuPLThooA+jIbZhSAfoBDklTluWLKkn4zpX/xnPAbAk7ojGPm4Egb+9fxvQVJydIahZZ/I6eLpY5PSsR2t2kS255kcm/UpLS4llat41wCtdXDJPcq5ep0+nOr6jyq6upRsm0tQufN5CM7ys50= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767010889; c=relaxed/simple; bh=bvZPWtH78xTFw0Hg8Tkzsnnxi9M7OqZGUKF6dIsCZ4k=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=dGjzf3kolgxiBo5SoNj/agfRXWrbx9++v9MKBwwprG76C2nP5rHipgYp2mgVTSqI9Iq3lfHkgugbuf9PkPMGXMn1t84FYpH/Z3+Qwfbuh7tuHrsFeltwPY7107VbZ96nfZ1vQwdSvuEN5ONkLHf4nLuTQTva4oo4ePJW2G/kjgg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0BJMoExz; 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="0BJMoExz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A6BD6C116C6; Mon, 29 Dec 2025 12:21:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1767010889; bh=bvZPWtH78xTFw0Hg8Tkzsnnxi9M7OqZGUKF6dIsCZ4k=; h=Subject:To:Cc:From:Date:From; b=0BJMoExz7ApQlx+uivIzxk8mB330X+8EYG/NrfW868YNM6eTpbtkPpU50sMrBSAce dYGcmESFEjgLCJAZUvpGSRlJKBZMh9PLe1exl/7NZkSCpLkkIb1OusBGz12cm5CUct O1RveYfGtgfjqeeAvp7pk2Z9xdOb/CsqXQXEIev0= Subject: FAILED: patch "[PATCH] io_uring/poll: correctly handle io_poll_add() return value on" failed to apply to 6.6-stable tree To: axboe@kernel.dk Cc: From: Date: Mon, 29 Dec 2025 13:21:26 +0100 Message-ID: <2025122926-disarray-agile-9880@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 6.6-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-6.6.y git checkout FETCH_HEAD git cherry-pick -x 84230ad2d2afbf0c44c32967e525c0ad92e26b4e # git commit -s git send-email --to '' --in-reply-to '2025122926-disarray-agile-9880@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 84230ad2d2afbf0c44c32967e525c0ad92e26b4e Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 1 Dec 2025 13:25:22 -0700 Subject: [PATCH] io_uring/poll: correctly handle io_poll_add() return value on update 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 diff --git a/io_uring/poll.c b/io_uring/poll.c index 8aa4e3a31e73..3f1d716dcfab 100644 --- a/io_uring/poll.c +++ b/io_uring/poll.c @@ -937,12 +937,17 @@ int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags) ret2 = io_poll_add(preq, issue_flags & ~IO_URING_F_UNLOCKED); /* successfully updated, don't complete poll request */ - if (!ret2 || ret2 == -EIOCBQUEUED) + if (ret2 == IOU_ISSUE_SKIP_COMPLETE) goto out; + /* request completed as part of the update, complete it */ + else if (ret2 == IOU_COMPLETE) + goto complete; } - req_set_fail(preq); io_req_set_res(preq, -ECANCELED, 0); +complete: + if (preq->cqe.res < 0) + req_set_fail(preq); preq->io_task_work.func = io_req_task_complete; io_req_task_work_add(preq); out: