From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 67AFB400984; Thu, 16 Jul 2026 13:43:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784209439; cv=none; b=JSGgLvCmPXZkuV4wHxgj3vvXSBwBhJEV1Wg2UtnidlGCHeFKotYEl69rFARsG4FVFlKWe5wI9LtBK+sNu8TdVhqpEEsqO8daHr1FepsQxbsVm0XecfdTHHkqbmC/u8h7kW707Xkfbb164NogoLWR/ZuNFHWER3AdE1RD3DjS2k0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784209439; c=relaxed/simple; bh=8Ub5g93GpZ7MbBpkyWoFKuTTox7k3s7TZYEbmvClokA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gk826OW70QUj2FharMFIPM+Ev1tsu0L8S81On0Tizx8fW+/zQUNQlyImBuNNoVx1aS7i13B4SnfGYT6/A7kuipmJnZti9311egHfcimSLOux6V87F0Q+yPUVDRLyAH5SEcyvaCMsldSYwjwf3f0N+3wFspypovelZcQ3N+o8ksc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=sY+Mwn2c; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="sY+Mwn2c" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC4A81F000E9; Thu, 16 Jul 2026 13:43:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784209437; bh=pC+jg4xH6q5QD/BZAG2X8ECUjolJG69VqWZmjP5VC/o=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=sY+Mwn2cLIFWMT9reEqvUYbsWM7phUIyx6Cc1XsO/vJ/McSNYIVgrOhGJbBr8HPak N2sDyjO+H6CSjBw/0zEdIDYVpOGaXVPpBJ/2CDG5b3sejzMYiQVdMw+8O3JyI/XDzR sh/d7qhR5sucZ5/MZsKrKkwfNg1cSEBG448KHAck= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Runyu Xiao , Jens Axboe Subject: [PATCH 7.1 185/518] io_uring/io-wq: re-check IO_WQ_BIT_EXIT for each linked work item Date: Thu, 16 Jul 2026 15:27:33 +0200 Message-ID: <20260716133051.884406112@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260716133047.772246337@linuxfoundation.org> References: <20260716133047.772246337@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Runyu Xiao commit 29bef9934b2521f787bb15dd1985d4c0d12ae02a upstream. commit 10dc95939817 ("io_uring/io-wq: check IO_WQ_BIT_EXIT inside work run loop") fixed the obvious case where io_worker_handle_work() took one exit-bit snapshot before draining pending work, but the fix stops one level too early. io_worker_handle_work() now re-checks IO_WQ_BIT_EXIT in its outer work run loop, yet it still snapshots that bit once before processing a whole dependent linked-work chain. If io_wq_exit_start() sets IO_WQ_BIT_EXIT after the first linked item has started, the remaining linked items can still reuse stale do_kill = false, skip IO_WQ_WORK_CANCEL, and continue running after exit has begun. Move the check further inside, so it covers linked items too. Note: this is a syzbot special as it loves setting up tons of slow linked work on weird devices like msr that take forever to read, and immediately close the ring. Exit then takes a long time. Fixes: 10dc95939817 ("io_uring/io-wq: check IO_WQ_BIT_EXIT inside work run loop") Cc: stable@vger.kernel.org Signed-off-by: Runyu Xiao Link: https://patch.msgid.link/20260527172203.2043962-1-runyu.xiao@seu.edu.cn Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- io_uring/io-wq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/io_uring/io-wq.c +++ b/io_uring/io-wq.c @@ -602,7 +602,6 @@ static void io_worker_handle_work(struct struct io_wq *wq = worker->wq; do { - bool do_kill = test_bit(IO_WQ_BIT_EXIT, &wq->state); struct io_wq_work *work; /* @@ -638,6 +637,7 @@ static void io_worker_handle_work(struct /* handle a whole dependent link */ do { + bool do_kill = test_bit(IO_WQ_BIT_EXIT, &wq->state); struct io_wq_work *next_hashed, *linked; unsigned int work_flags = atomic_read(&work->flags); unsigned int hash = __io_wq_is_hashed(work_flags)