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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 EB915C43140 for ; Thu, 21 Jun 2018 13:27:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A164A20883 for ; Thu, 21 Jun 2018 13:27:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A164A20883 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933013AbeFUN1f (ORCPT ); Thu, 21 Jun 2018 09:27:35 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:34082 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932677AbeFUN1e (ORCPT ); Thu, 21 Jun 2018 09:27:34 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id F3FC44010227; Thu, 21 Jun 2018 13:27:33 +0000 (UTC) Received: from 192.168.1.107 (ovpn-12-52.pek2.redhat.com [10.72.12.52]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 8CCC12156880; Thu, 21 Jun 2018 13:27:28 +0000 (UTC) Subject: Re: [PATCH 2/4 V3] Allocate pages for kdump without encryption when SME is enabled To: Baoquan He Cc: linux-kernel@vger.kernel.org, thomas.lendacky@amd.com, iommu@lists.linux-foundation.org, dyoung@redhat.com, kexec@lists.infradead.org References: <20180616082714.32035-1-lijiang@redhat.com> <20180616082714.32035-3-lijiang@redhat.com> <20180621015306.GG29979@MiWiFi-R3L-srv> <20180621102321.GK29979@MiWiFi-R3L-srv> From: lijiang Message-ID: <49706f0e-03b6-8c43-c35f-c0b0338a17bd@redhat.com> Date: Thu, 21 Jun 2018 21:27:23 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: <20180621102321.GK29979@MiWiFi-R3L-srv> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Thu, 21 Jun 2018 13:27:34 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Thu, 21 Jun 2018 13:27:34 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'lijiang@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2018年06月21日 18:23, Baoquan He 写道: > On 06/21/18 at 01:06pm, lijiang wrote: >> 在 2018年06月21日 09:53, Baoquan He 写道: >>> On 06/16/18 at 04:27pm, Lianbo Jiang wrote: >>>> When SME is enabled in the first kernel, we will allocate pages >>>> for kdump without encryption in order to be able to boot the >>>> second kernel in the same manner as kexec, which helps to keep >>>> the same code style. >>>> >>>> Signed-off-by: Lianbo Jiang >>>> --- >>>> kernel/kexec_core.c | 12 ++++++++++++ >>>> 1 file changed, 12 insertions(+) >>>> >>>> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c >>>> index 20fef1a..3c22a9b 100644 >>>> --- a/kernel/kexec_core.c >>>> +++ b/kernel/kexec_core.c >>>> @@ -471,6 +471,16 @@ static struct page *kimage_alloc_crash_control_pages(struct kimage *image, >>>> } >>>> } >>>> >>>> + if (pages) { >>>> + unsigned int count, i; >>>> + >>>> + pages->mapping = NULL; >>>> + set_page_private(pages, order); >>>> + count = 1 << order; >>>> + for (i = 0; i < count; i++) >>>> + SetPageReserved(pages + i); >>> >>> I guess you might imitate the kexec case, however kexec get pages from >>> buddy. Crash pages are reserved in memblock, these codes might make no sense. >>> >> Thanks for your comments. >> We have changed the attribute of pages, so the original attribute of pages will be >> restored when they free. > > Hmm, you can check what kimage_free() is doing, and where > kimage->control_pages, dest_pages, unusable_pages is assigned. Do you > know where these original attribute of pages comes from and they are > used/needed in CRASH case, if you care about them? > Originally, we want to have an opportunity to restore the previous attribute of pages, that should be more better if the pages are remembered in 'image->control_pages'. If we remove these codes, it is also harmless for kdump, but it will become strange, maybe someone could ask where to restore the previous attribute of pages. Thanks. >> >>>> + arch_kexec_post_alloc_pages(page_address(pages), 1 << order, 0); >>>> + } >>>> return pages; >>>> } >>>> >>>> @@ -865,6 +875,7 @@ static int kimage_load_crash_segment(struct kimage *image, >>>> result = -ENOMEM; >>>> goto out; >>>> } >>>> + arch_kexec_post_alloc_pages(page_address(page), 1, 0); >>>> ptr = kmap(page); >>>> ptr += maddr & ~PAGE_MASK; >>>> mchunk = min_t(size_t, mbytes, >>>> @@ -882,6 +893,7 @@ static int kimage_load_crash_segment(struct kimage *image, >>>> result = copy_from_user(ptr, buf, uchunk); >>>> kexec_flush_icache_page(page); >>>> kunmap(page); >>>> + arch_kexec_pre_free_pages(page_address(page), 1); >>>> if (result) { >>>> result = -EFAULT; >>>> goto out; >>>> -- >>>> 2.9.5 >>>> >>>> >>>> _______________________________________________ >>>> kexec mailing list >>>> kexec@lists.infradead.org >>>> http://lists.infradead.org/mailman/listinfo/kexec