From patchwork Wed Aug 18 00:29:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Luck X-Patchwork-Id: 12442407 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 8F076C4320A for ; Wed, 18 Aug 2021 00:29:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 73D9561051 for ; Wed, 18 Aug 2021 00:29:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235847AbhHRAa1 (ORCPT ); Tue, 17 Aug 2021 20:30:27 -0400 Received: from mga12.intel.com ([192.55.52.136]:60945 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234818AbhHRAa0 (ORCPT ); Tue, 17 Aug 2021 20:30:26 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10079"; a="195807460" X-IronPort-AV: E=Sophos;i="5.84,330,1620716400"; d="scan'208";a="195807460" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Aug 2021 17:29:52 -0700 X-IronPort-AV: E=Sophos;i="5.84,330,1620716400"; d="scan'208";a="520687348" Received: from agluck-desk2.sc.intel.com ([10.3.52.146]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Aug 2021 17:29:52 -0700 From: Tony Luck To: Borislav Petkov Cc: Jue Wang , Ding Hui , naoya.horiguchi@nec.com, osalvador@suse.de, Youquan Song , huangcun@sangfor.com.cn, x86@kernel.org, linux-edac@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Tony Luck Subject: [PATCH v2 3/3] x86/mce: Drop copyin special case for #MC Date: Tue, 17 Aug 2021 17:29:42 -0700 Message-Id: <20210818002942.1607544-4-tony.luck@intel.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210818002942.1607544-1-tony.luck@intel.com> References: <20210706190620.1290391-1-tony.luck@intel.com> <20210818002942.1607544-1-tony.luck@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org Fixes to the iterator code to handle faults that are not on page boundaries mean that the special case for machine check during copy from user is no longer needed. Signed-off-by: Tony Luck --- arch/x86/lib/copy_user_64.S | 13 ------------- 1 file changed, 13 deletions(-) diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S index 57b79c577496..2797e630b9b1 100644 --- a/arch/x86/lib/copy_user_64.S +++ b/arch/x86/lib/copy_user_64.S @@ -234,24 +234,11 @@ EXPORT_SYMBOL(copy_user_enhanced_fast_string) */ SYM_CODE_START_LOCAL(.Lcopy_user_handle_tail) movl %edx,%ecx - cmp $X86_TRAP_MC,%eax /* check if X86_TRAP_MC */ - je 3f 1: rep movsb 2: mov %ecx,%eax ASM_CLAC ret - /* - * Return zero to pretend that this copy succeeded. This - * is counter-intuitive, but needed to prevent the code - * in lib/iov_iter.c from retrying and running back into - * the poison cache line again. The machine check handler - * will ensure that a SIGBUS is sent to the task. - */ -3: xorl %eax,%eax - ASM_CLAC - ret - _ASM_EXTABLE_CPY(1b, 2b) SYM_CODE_END(.Lcopy_user_handle_tail)