From patchwork Fri Jun 5 14:14:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 224809 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0646EC433DF for ; Fri, 5 Jun 2020 14:16:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D19E82086A for ; Fri, 5 Jun 2020 14:16:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591366591; bh=fCZJ/XHdKHiSHStzGsvusFWRTMUu6YnQ/9xTD63G/qo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mGXFLH4fG3oLRTPi5RnsMKPO6NLmZyo4jU8UdTCPhrk0hGw3apj3mEENh1u9xNRWh 0JwIbDXdfh7SdtJr9sOzLJAOCPBaxFN1ZlSVHIrbFWX3MeA8wF2n1jD6sZwHsm7BH+ r7GZIgOt2ZVvZfBrT0KRnsQh/IdFxlUGBrOaTenk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728243AbgFEOQa (ORCPT ); Fri, 5 Jun 2020 10:16:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:45582 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728232AbgFEOQ1 (ORCPT ); Fri, 5 Jun 2020 10:16:27 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EA97B20897; Fri, 5 Jun 2020 14:16:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591366587; bh=fCZJ/XHdKHiSHStzGsvusFWRTMUu6YnQ/9xTD63G/qo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=z1X+6oRCd7Kn1j74iZ7kmRjhzofJnOe2V/Q3lnPLca3EyQbexxd7NQhiGHvzryfaz THZM3TiG+2HhGWhCWZ8dh77scOw5nvWl3NzXhVjlO3+hRq1dKBhnimxvu3hV7LEtKC gT5fAeNaPc5qTK1m1OMugLE2Tao31LQx8MM9qqj4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pavel Begunkov , Jens Axboe , Sasha Levin Subject: [PATCH 5.6 13/43] io_uring: dont prepare DRAIN reqs twice Date: Fri, 5 Jun 2020 16:14:43 +0200 Message-Id: <20200605140153.218553972@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200605140152.493743366@linuxfoundation.org> References: <20200605140152.493743366@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Pavel Begunkov [ Upstream commit 650b548129b60b0d23508351800108196f4aa89f ] If req->io is not NULL, it's already prepared. Don't do it again, it's dangerous. Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- fs/io_uring.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 8bdf2629f7fd..aa800f70c55e 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -4262,12 +4262,13 @@ static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe) if (!req_need_defer(req) && list_empty_careful(&ctx->defer_list)) return 0; - if (!req->io && io_alloc_async_ctx(req)) - return -EAGAIN; - - ret = io_req_defer_prep(req, sqe); - if (ret < 0) - return ret; + if (!req->io) { + if (io_alloc_async_ctx(req)) + return -EAGAIN; + ret = io_req_defer_prep(req, sqe); + if (ret < 0) + return ret; + } spin_lock_irq(&ctx->completion_lock); if (!req_need_defer(req) && list_empty(&ctx->defer_list)) {