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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 5F6A8C43381 for ; Mon, 25 Mar 2019 06:19:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2FA5E2087F for ; Mon, 25 Mar 2019 06:19:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729689AbfCYGTi (ORCPT ); Mon, 25 Mar 2019 02:19:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37952 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729568AbfCYGTh (ORCPT ); Mon, 25 Mar 2019 02:19:37 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B36D8308FED2; Mon, 25 Mar 2019 06:19:36 +0000 (UTC) Received: from dhcp-128-65.nay.redhat.com (ovpn-12-109.pek2.redhat.com [10.72.12.109]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9F4F660BF7; Mon, 25 Mar 2019 06:19:33 +0000 (UTC) Date: Mon, 25 Mar 2019 14:19:29 +0800 From: Dave Young To: Junichi Nomura Cc: "fanc.fnst@cn.fujitsu.com" , "x86@kernel.org" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Borislav Petkov , "bp@suse.de" Subject: Re: [PATCH] x86/boot: Use EFI setup data if provided Message-ID: <20190325061929.GC9385@dhcp-128-65.nay.redhat.com> References: <20190322110342.GA16202@jeru.linux.bs1.fc.nec.co.jp> <20190322152328.GD12472@zn.tnic> <20190325002740.GA6637@jeru.linux.bs1.fc.nec.co.jp> <20190325060128.GB9385@dhcp-128-65.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190325060128.GB9385@dhcp-128-65.nay.redhat.com> User-Agent: Mutt/1.11.3 (2019-02-01) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Mon, 25 Mar 2019 06:19:36 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/25/19 at 02:01pm, Dave Young wrote: > On 03/25/19 at 12:27am, Junichi Nomura wrote: > > On Fri, Mar 22, 2019 at 04:23:28PM +0100, Borislav Petkov wrote: > > > On Fri, Mar 22, 2019 at 11:03:43AM +0000, Junichi Nomura wrote: > > > > Commit 3a63f70bf4c3a ("x86/boot: Early parse RSDP and save it in > > > > boot_params") broke kexec boot on EFI systems. efi_get_rsdp_addr() > > > > in the early parsing code tries to search RSDP from EFI table but > > > > whose address is virtual. > > > > > > > > Since kexec(1) provides physical address of config_table via boot_params, > > > > efi_get_rsdp_addr() should look for setup_data in the same way as > > > > efi_systab_init() in arch/x86/platform/efi/efi.c does. > > > > > > If the kexec kernel should continue to use efi_systab_init() then you > > > should make efi_get_rsdp_addr() exit early in the kexec-ed kernel. > > > > I'm not sure which way kexec devel is going. Added kexec list. > > Here is the version that exits early in efi_get_rsdp_addr(). > > > > [PATCH] x86/boot: Don't try to search RSDP from EFI when kexec-booted > > > > Commit 3a63f70bf4c3a ("x86/boot: Early parse RSDP and save it in > > boot_params") broke kexec boot on EFI systems. efi_get_rsdp_addr() > > in the early parsing code tries to search RSDP from EFI table but > > whose address is virtual. > > > > Normally kexec(1) provides physical address of config_table via boot_params > > and EFI code uses that during initialization. > > For the early boot code, we just exit efi_get_rsdp_addr() early if the kernel > > is booted by kexec. > > > > Fixes: 3a63f70bf4c3a ("x86/boot: Early parse RSDP and save it in boot_params") > > Signed-off-by: Jun'ichi Nomura > > Cc: Chao Fan > > Cc: Borislav Petkov > > > > diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c > > index 0ef4ad5..1cefc43 100644 > > --- a/arch/x86/boot/compressed/acpi.c > > +++ b/arch/x86/boot/compressed/acpi.c > > @@ -44,6 +44,24 @@ static acpi_physical_address get_acpi_rsdp(void) > > return addr; > > } > > > > +static bool is_kexec_booted(void) > > +{ > > + struct setup_data *data; > > + > > + /* > > + * kexec-tools provides EFI setup data so that kexec-ed kernel > > + * can find proper tables. > > + */ > > + data = (struct setup_data *) boot_params->hdr.setup_data; > > + while (data) { > > + if (data->type == SETUP_EFI) > > + return true; > > + data = (struct setup_data *) data->next; > > + } > > + > > + return false; > > +} > > + > > /* Search EFI system tables for RSDP. */ > > static acpi_physical_address efi_get_rsdp_addr(void) > > { > > @@ -57,6 +75,10 @@ static acpi_physical_address efi_get_rsdp_addr(void) > > int size, i; > > char *sig; > > > > + /* If the system is kexec-booted, poking EFI systab may not work. */ > > + if (is_kexec_booted()) > > + return 0; > > + > > ei = &boot_params->efi_info; > > sig = (char *)&ei->efi_loader_signature; > > > > > > _______________________________________________ > > kexec mailing list > > kexec@lists.infradead.org > > http://lists.infradead.org/mailman/listinfo/kexec > > Good catch, this way looks good to me. But the function > is_kexec_booted can be compiled when #ifdef CONFIG_EFI > > Otherwise: > > Acked-by: Dave Young > Hold on, I replied too quick. One question is does the above patch passed your test? It can workaround and skip the wrong phys addr issue, but the acpi early parsing still fails because efi_get_rsdp_addr return 0? If this is the case you may need go with your old patch. I think normally people do not see this bug, because kernel will set the rsdp in boot_params->acpi_rsdp_addr. Maybe you are testing with different kernel versions, eg. old kernel kexec to new kernel. And the old kernel does not set boot_params->acpi_rsdp_addr Is this correct? Thanks Dave