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=-13.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 2EB7EC433ED for ; Sat, 15 May 2021 15:30:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 085AB611C9 for ; Sat, 15 May 2021 15:30:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232658AbhEOPbq (ORCPT ); Sat, 15 May 2021 11:31:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:33114 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232483AbhEOPbf (ORCPT ); Sat, 15 May 2021 11:31:35 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 136E1611C9; Sat, 15 May 2021 15:30:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1621092622; bh=GvpOdLUN0BGGVqLx+hc71U4t5c+VkOe8e4mFWqfjXQ8=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=ZQxYSeTYPcDcDgDbt7aoO9YAZtoRFRxwwL5RnbAwsSYdvG83qx0XtFKiFvsxB9pXi utt2eD4j8xvKeNhtxF6CE17aBwwLrtRaY3KGjOmkJpzcqVlASBSDGfPNjhGwu1lsag yy2EWc3hhODxf797rScxP+9IkifgA+u9LC0VplxgUImQyvKp/KbCfWr9+KCOIbg1Qv 0j+tFIeLesu6Oiw25XC+ziv8t35QnUL+pizzCSYiWehiRgnIUm+Hk/Fl8pUV9Y8Ctf RLXoBEBGjeAMGvLAYF6acv3XA5zkwDZRUDr4lYcVN0Lp/jkSm4yn180OXPP3vScs+8 7l7yV4cC6HjdA== Subject: Re: [PATCH v2 6/9] x86/kexec: set_[gi]dt() -> native_[gi]dt_invalidate() in machine_kexec_*.c To: "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , Borislav Petkov Cc: Linux Kernel Mailing List References: <20210515014400.2999028-1-hpa@zytor.com> <20210515014400.2999028-7-hpa@zytor.com> From: Andy Lutomirski Message-ID: Date: Sat, 15 May 2021 08:30:21 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <20210515014400.2999028-7-hpa@zytor.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/14/21 6:43 PM, H. Peter Anvin wrote: > From: "H. Peter Anvin (Intel)" > > These files contain private set_gdt() functions which are only used to > invalid the gdt; machine_kexec_64.c also contains a set_idt() > function to invalidate the idt. > > phys_to_virt(0) *really* doesn't make any sense for creating an > invalid GDT. A NULL pointer (virtual 0) makes a lot more sense; > although neither will allow any actual memory reference, a NULL > pointer stands out more. > > Replace these calls with native_[gi]dt_invalidate(). > > Signed-off-by: H. Peter Anvin (Intel) Acked-by: Andy Lutomirski