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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 20F30C76195 for ; Sat, 25 Mar 2023 03:00:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=P8oNVAB1RyQhqlugHxU5X4iHpOWiB3YMRSkylUtDz1c=; b=mxQS2Itw6EYniV Q7HZHphPnSUwkh85SW4ycFyz4GWFDiLn2jV46qNbfDC0inH27OHUfiC7Pt1P33Jv9MO/3d4v06JUr YEjhFtHoO5XP7emsrNuOeCQvj/wjS7zYVxLTh1K8KZpQIGeQnESdTzYapJxjSC2Bc8GVdV+RmD/ZX vSUdK4HGx0uHNJBf2kKV6evDszn/qGyxeipzGl579LN596qx0rZRn5jiLEFX7sD1vSycMcOPRAp6S uN1lALt7C+ujdXpknfcv3fzu2PkCn9/WUQvxFyxAUiC+5R/pnRKRJ6xvrB/LqR341jLg6YfpS7Edy M+JuhBAue4kH4QRY/W/w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pfu8w-0060w6-2u; Sat, 25 Mar 2023 03:00:34 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pfu8t-0060uo-1Q for kexec@lists.infradead.org; Sat, 25 Mar 2023 03:00:33 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1679713227; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=aDkgtInWoMj0Kl4LkfGevv4ADacM/sg4LTkpZaBnKrc=; b=UgYRqXvVtMhnhb0UdUDBPpsrYHlHut5Uc+GdZvThZOCT5vvSQhd1rbrYxTmqjg49/zSl4u 5wpvMINnQSZzsVCK1ePIdxLU4u9UsLPVGFUu5Q3xsFOadXEfDYOblPserIhKgut+dS8qYj 51JhebjLUmgguudhlIQ+Y+kmPoDwtBg= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-632-thQ0X1QGPmmYShG0G3q_5A-1; Fri, 24 Mar 2023 23:00:23 -0400 X-MC-Unique: thQ0X1QGPmmYShG0G3q_5A-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5FC5887B2A1; Sat, 25 Mar 2023 03:00:22 +0000 (UTC) Received: from localhost (ovpn-12-29.pek2.redhat.com [10.72.12.29]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CD24140C6E67; Sat, 25 Mar 2023 03:00:15 +0000 (UTC) Date: Sat, 25 Mar 2023 11:00:11 +0800 From: Baoquan He To: "Leizhen (ThunderTown)" Cc: Catalin Marinas , linux-kernel@vger.kernel.org, horms@kernel.org, John.p.donnelly@oracle.com, will@kernel.org, kexec@lists.infradead.org, ardb@kernel.org, rppt@kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 0/3] arm64: kdump : take off the protection on crashkernel memory region Message-ID: References: <20230324131838.409996-1-bhe@redhat.com> <9ca6f729-989d-654a-83e6-c89d8f65c69d@huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <9ca6f729-989d-654a-83e6-c89d8f65c69d@huawei.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230324_200031_693289_6C186667 X-CRM114-Status: GOOD ( 16.48 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On 03/25/23 at 10:14am, Leizhen (ThunderTown) wrote: > > > On 2023/3/25 1:11, Catalin Marinas wrote: > > On Fri, Mar 24, 2023 at 09:18:35PM +0800, Baoquan He wrote: > >> Baoquan He (3): > >> arm64: kdump : take off the protection on crashkernel memory region > >> arm64: kdump: do not map crashkernel region specifically > >> arm64: kdump: defer the crashkernel reservation for platforms with no > >> DMA memory zones > >> > >> arch/arm64/include/asm/kexec.h | 6 ----- > >> arch/arm64/include/asm/memory.h | 5 ---- > >> arch/arm64/kernel/machine_kexec.c | 20 -------------- > >> arch/arm64/mm/init.c | 6 +---- > >> arch/arm64/mm/mmu.c | 43 ------------------------------- > >> 5 files changed, 1 insertion(+), 79 deletions(-) > > > > This series works for me and it has a negative diffstat as well (though > > I'm sure people will try to bring it back ;)). > > After the write protection is removed, it is recommended that crc32 check > be added. However, it can be added later. That's a great catch. We have calculated the checusum with sha256 in user space and kernel, and verify it in purgatory in user space. However, arm64 seems to not do the verifying in kernel if kexec_file_load is used. Please see kexec_calculate_store_digests(). If stamping happened, the checksum verification can help us spot it. Yes, this can be added later. Thanks for raising that. _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec