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[23.128.96.18]) by mx.google.com with ESMTP id i3si1713189edn.135.2020.05.01.07.12.22; Fri, 01 May 2020 07:12:45 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=kckmiiqb; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729288AbgEAOK5 (ORCPT + 99 others); Fri, 1 May 2020 10:10:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57258 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1729219AbgEAOKy (ORCPT ); Fri, 1 May 2020 10:10:54 -0400 Received: from mail-wr1-x443.google.com (mail-wr1-x443.google.com [IPv6:2a00:1450:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7F96EC061A0C; Fri, 1 May 2020 07:10:54 -0700 (PDT) Received: by mail-wr1-x443.google.com with SMTP id g13so11642843wrb.8; Fri, 01 May 2020 07:10:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=M/HjbUxD/OrDoik15Fa+gZu3/yY1bEZ62TD4ptiqSXA=; b=kckmiiqbEzAbel6pdnVbEDSy+pW8D0WJK1OZvYnksJUAhkt5Tz6/SF0CMeb6iFzpI8 4RhY/aus+atQ+Iy3xsb9aGeWhZ8IqnQ/kPROgLq7Mn8gdK/0O8mvLE3H5Ihfp+chIFdQ 13ak6/4FxVcQR3ptdXHI1K+ggyG2qwhjyv9z4UZz6K3blSJLE1nlUUt1qaM/4vN0Ejc3 emX4KOmQ66g5AMpwZWx1Rk+Ewy7/xz5+OCrURluri3z1kUcwNBcA4+/HO4hNZ99SKoPC fhoSaVXfxUSF+S1mkNJGWBPcE2BCWZULtlE1PPBBi62TzXSvelgEzjTPEwNF5UceDzbv Al5Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=M/HjbUxD/OrDoik15Fa+gZu3/yY1bEZ62TD4ptiqSXA=; b=C6FThzCOKJSX8vRE9+H73kFTiu36wTs6Y7yrZI2sW+M+Nlok/GbbAH2ZL7O0L8ESQC s2f45y6Nh/wsJYwGNxagNWajgsOR2wVTKlf9EytCaiHUIrQZ+dmy/KxUGLiI2EyGwkpb 6WzWnwW4W5QkcjgQGITzNMJ1qJyP/FxZRk0Vk1EIaYwTr3X/12lciwSDptmQbkRrgf+J Rc0MOxaofOEjJryQo+/28+wp/GW5LeMvPIhWFwT5HXcjdI4Tg1gxjjjnkDnpG64xm1In FswhBO4fkuO2eRPqbXyXg0EkLfyaXlVCBnRAMED1+y4IVW08TRD2rviMDhq41dNLpAkw GB8A== X-Gm-Message-State: AGi0Pua5YJspWn/f61/Jksz7e3JZ+TvNOlDO3ANT6IkzLBaKyLS2UgmV p4K+0j1ABVJJ1EJO3TlHhLI= X-Received: by 2002:a5d:66ce:: with SMTP id k14mr4707770wrw.73.1588342252993; Fri, 01 May 2020 07:10:52 -0700 (PDT) Received: from localhost.localdomain ([109.126.133.135]) by smtp.gmail.com with ESMTPSA id j17sm4837390wrb.46.2020.05.01.07.10.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 01 May 2020 07:10:52 -0700 (PDT) From: Pavel Begunkov To: Jens Axboe , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/3] io_uring: check non-sync defer_list carefully Date: Fri, 1 May 2020 17:09:37 +0300 Message-Id: X-Mailer: git-send-email 2.24.0 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org io_req_defer() do double-checked locking. Use proper helpers for that, i.e. list_empty_careful(). Signed-off-by: Pavel Begunkov --- fs/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index e7d7e83e3d56..e5d560f2ce12 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -5028,7 +5028,7 @@ static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe) int ret; /* Still need defer if there is pending req in defer list. */ - if (!req_need_defer(req) && list_empty(&ctx->defer_list)) + if (!req_need_defer(req) && list_empty_careful(&ctx->defer_list)) return 0; if (!req->io && io_alloc_async_ctx(req)) -- 2.24.0