From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-6.0 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 47F867D089 for ; Tue, 18 Dec 2018 07:34:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726346AbeLRHey (ORCPT ); Tue, 18 Dec 2018 02:34:54 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47778 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726316AbeLRHey (ORCPT ); Tue, 18 Dec 2018 02:34:54 -0500 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 666C5C02E632; Tue, 18 Dec 2018 07:34:54 +0000 (UTC) Received: from localhost.localdomain (ovpn-12-60.pek2.redhat.com [10.72.12.60]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7D3D7100190E; Tue, 18 Dec 2018 07:34:47 +0000 (UTC) Subject: Re: [PATCH 2/2 v3] kdump,vmcoreinfo: Export the value of sme mask to vmcoreinfo To: Borislav Petkov Cc: linux-kernel@vger.kernel.org, kexec@lists.infradead.org, tglx@linutronix.de, mingo@redhat.com, x86@kernel.org, akpm@linux-foundation.org, bhe@redhat.com, dyoung@redhat.com, linux-doc@vger.kernel.org References: <20181216131617.2612-1-lijiang@redhat.com> <20181216131617.2612-3-lijiang@redhat.com> <20181217130129.GE12165@zn.tnic> From: lijiang Message-ID: Date: Tue, 18 Dec 2018 15:34:43 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181217130129.GE12165@zn.tnic> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Tue, 18 Dec 2018 07:34:54 +0000 (UTC) Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org 在 2018年12月17日 21:01, Borislav Petkov 写道: > On Sun, Dec 16, 2018 at 09:16:17PM +0800, Lianbo Jiang wrote: >> For AMD machine with SME feature, makedumpfile tools need to know >> whether the crash kernel was encrypted or not. If SME is enabled >> in the first kernel, the crash kernel's page table(pgd/pud/pmd/pte) >> contains the memory encryption mask, so need to remove the sme mask >> to obtain the true physical address. >> >> Signed-off-by: Lianbo Jiang >> --- >> arch/x86/kernel/machine_kexec_64.c | 14 ++++++++++++++ >> 1 file changed, 14 insertions(+) >> >> diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c >> index 4c8acdfdc5a7..1860fe24117d 100644 >> --- a/arch/x86/kernel/machine_kexec_64.c >> +++ b/arch/x86/kernel/machine_kexec_64.c >> @@ -352,10 +352,24 @@ void machine_kexec(struct kimage *image) >> >> void arch_crash_save_vmcoreinfo(void) >> { >> + u64 sme_mask = sme_me_mask; >> + >> VMCOREINFO_NUMBER(phys_base); >> VMCOREINFO_SYMBOL(init_top_pgt); >> vmcoreinfo_append_str("NUMBER(pgtable_l5_enabled)=%d\n", >> pgtable_l5_enabled()); >> + /* >> + * Currently, the local variable 'sme_mask' stores the value of >> + * sme_me_mask(bit 47), and also write the value of sme_mask to >> + * the vmcoreinfo. >> + * If need, the bit(sme_mask) might be redefined in the future, >> + * but the 'bit63' will be reserved. >> + * For example: >> + * [ misc ][ enc bit ][ other misc SME info ] >> + * 0000_0000_0000_0000_1000_0000_0000_0000_0000_0000_..._0000 >> + * 63 59 55 51 47 43 39 35 31 27 ... 3 >> + */ > > This text belongs into the document. > Ok, i will move it into VMCOREINFO document. Thanks.