From mboxrd@z Thu Jan 1 00:00:00 1970 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=-8.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 B32D1C4741F for ; Sat, 26 Sep 2020 04:19:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 78416208FE for ; Sat, 26 Sep 2020 04:19:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601093966; bh=4XYbOkZD/X+maFrZDRd5RAzqJJ9LoJUpJToY3T3h3R0=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=0OjTe+COY0QbO2FP/yJi5tuY5CYV8IfSrpcuMwH7JHSVtjNXUSiWOUTfRyx2NFYr8 5++Vg2fljktz75atWHhlKJIyKB9Z5oMEQgDkoZslPWh3YVM8/dcz/VfKYXZ0dvgmBO ywDX7eKIMEwE3wKXmEBSENS0q7VEY0vlQVAn2Uvc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730015AbgIZET0 (ORCPT ); Sat, 26 Sep 2020 00:19:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:52008 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729035AbgIZET0 (ORCPT ); Sat, 26 Sep 2020 00:19:26 -0400 Received: from localhost.localdomain (c-71-198-47-131.hsd1.ca.comcast.net [71.198.47.131]) (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 DF92D207C4; Sat, 26 Sep 2020 04:19:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601093965; bh=4XYbOkZD/X+maFrZDRd5RAzqJJ9LoJUpJToY3T3h3R0=; h=Date:From:To:Subject:In-Reply-To:From; b=ARY3by6ITqp2ZnsjOsPvXl+rGGDcHv8XbLOpId2hoXAJYDuU33VhrEDACHeGCnZjR 9n91SUl1xCKp3tjXuT8Qf0r7v9lmsrcvsunSEVd4++RIROvmA21hg5jWaBnCAd9vFX cwn6ysHBq1VfNYgqtGTRudh+891wxKG0QhjTznM0= Date: Fri, 25 Sep 2020 21:19:24 -0700 From: Andrew Morton To: akpm@linux-foundation.org, dan.j.wiilliams@intel.com, hch@lst.de, hpa@zytor.com, jack@suse.cz, jmoyer@redhat.com, linux-mm@kvack.org, mawilcox@microsoft.com, mingo@elte.hu, mingo@redhat.com, mm-commits@vger.kernel.org, mpatocka@redhat.com, ross.zwisler@linux.intel.com, stable@vger.kernel.org, tglx@linutronix.de, torvalds@linux-foundation.org, toshi.kani@hpe.com, viro@zeniv.linux.org.uk Subject: [patch 7/9] arch/x86/lib/usercopy_64.c: fix __copy_user_flushcache() cache writeback Message-ID: <20200926041924.JrUcL1D_9%akpm@linux-foundation.org> In-Reply-To: <20200925211725.0fea54be9e9715486efea21f@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Mikulas Patocka Subject: arch/x86/lib/usercopy_64.c: fix __copy_user_flushcache() cache writeback If we copy less than 8 bytes and if the destination crosses a cache line, __copy_user_flushcache would invalidate only the first cache line. This patch makes it invalidate the second cache line as well. Link: https://lkml.kernel.org/r/alpine.LRH.2.02.2009161451140.21915@file01.intranet.prod.int.rdu2.redhat.com Fixes: 0aed55af88345b ("x86, uaccess: introduce copy_from_iter_flushcache for pmem / cache-bypass operations") Signed-off-by: Mikulas Patocka Reviewed-by: Dan Williams Cc: Jan Kara Cc: Jeff Moyer Cc: Ingo Molnar Cc: Christoph Hellwig Cc: Toshi Kani Cc: "H. Peter Anvin" Cc: Al Viro Cc: Thomas Gleixner Cc: Matthew Wilcox Cc: Ross Zwisler Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Signed-off-by: Andrew Morton --- arch/x86/lib/usercopy_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/lib/usercopy_64.c~arch-x86-lib-usercopy_64c-fix-__copy_user_flushcache-cache-writeback +++ a/arch/x86/lib/usercopy_64.c @@ -120,7 +120,7 @@ long __copy_user_flushcache(void *dst, c */ if (size < 8) { if (!IS_ALIGNED(dest, 4) || size != 4) - clean_cache_range(dst, 1); + clean_cache_range(dst, size); } else { if (!IS_ALIGNED(dest, 8)) { dest = ALIGN(dest, boot_cpu_data.x86_clflush_size); _