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 148CFC43381 for ; Thu, 28 Mar 2019 23:11:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0A892184C for ; Thu, 28 Mar 2019 23:11:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728500AbfC1XLH (ORCPT ); Thu, 28 Mar 2019 19:11:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57140 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727670AbfC1XLH (ORCPT ); Thu, 28 Mar 2019 19:11:07 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5A8643086223; Thu, 28 Mar 2019 23:11:06 +0000 (UTC) Received: from localhost (ovpn-12-24.pek2.redhat.com [10.72.12.24]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 577A6600C0; Thu, 28 Mar 2019 23:11:03 +0000 (UTC) Date: Fri, 29 Mar 2019 07:11:00 +0800 From: "bhe@redhat.com" To: Junichi Nomura Cc: Borislav Petkov , Dave Young , "fanc.fnst@cn.fujitsu.com" , "kasong@redhat.com" , "x86@kernel.org" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v2] x86/boot: Use EFI setup data if provided Message-ID: <20190328231100.GC1877@MiWiFi-R3L-srv> References: <701c8e69-e1d4-c653-1d87-1c41789d3d54@ce.jp.nec.com> <20190325120149.GI12016@zn.tnic> <20190325122302.GC13160@dhcp-128-65.nay.redhat.com> <20190325123229.GL12016@zn.tnic> <20190325231000.GA9184@jeru.linux.bs1.fc.nec.co.jp> <20190326135714.GG1867@zn.tnic> <20190327014852.GA3659@MiWiFi-R3L-srv> <73322ba9-e436-68db-7863-afd31607d969@ce.jp.nec.com> <20190328064343.GA1877@MiWiFi-R3L-srv> <20190328074337.GA9470@jeru.linux.bs1.fc.nec.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190328074337.GA9470@jeru.linux.bs1.fc.nec.co.jp> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Thu, 28 Mar 2019 23:11:06 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/28/19 at 07:43am, Junichi Nomura wrote: > On 2019/03/28 15:43, bhe@redhat.com wrote: > > On 03/28/19 at 04:17am, Junichi Nomura wrote: > >> I still don't get it... We still need systab for kexec case as well > >> to get nr_tables. Don't we? > > > > Yes, simpler. > > > > As Dave replied in another mail, efi/kexec is only added for x86_64. See > > how it does in setup_linux_system_parameters() of kexec_tools utility, > > and we only have bzImage64 handling in kernel for kexec_file loading, > > see prepare_add_efi_setup_data(). > > > > You may only need to get kexec ei_info to use directly. > > OK, let me try. How does this look? Yes, it looks great. Thanks. Some tiny concenrns added in inline comments, please check. > > 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 > that will crash because the table address is virtual when the kernel > was booted by kexec. > > Since kexec(1) provides physical address of the table via efi_setup_data, > early boot code of kexec-ed kernel should look for setup_data in the same > way as efi_systab_init() in arch/x86/platform/efi/efi.c does. > > 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 > Cc: Dave Young > Cc: Baoquan He > > diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c > --- a/arch/x86/boot/compressed/acpi.c > +++ b/arch/x86/boot/compressed/acpi.c > @@ -44,17 +44,106 @@ static acpi_physical_address get_acpi_rsdp(void) > return addr; > } > > +static unsigned long efi_get_kexec_setup_data_addr(void) > +{ > +#ifdef CONFIG_EFI > + struct setup_data *data; > + u64 pa_data; > + > + pa_data = boot_params->hdr.setup_data; > + while (pa_data) { > + data = (struct setup_data *) pa_data; > + if (data->type == SETUP_EFI) > + return pa_data + sizeof(struct setup_data); > + pa_data = data->next; > + } > +#endif > + return 0; > +} > + > /* Search EFI system tables for RSDP. */ > -static acpi_physical_address efi_get_rsdp_addr(void) > +static acpi_physical_address __efi_get_rsdp_addr(unsigned long config_tables, unsigned int nr_tables, int size, bool efi_64) Here parameter 'size' and 'efi_64' seems a little duplicated on functionality. Only passing efi_64 can deduce the size? Personal opinion. > { > acpi_physical_address rsdp_addr = 0; > > #ifdef CONFIG_EFI > - unsigned long systab, systab_tables, config_tables; > + int i; > + > + /* Get EFI tables from systab. */ > + for (i = 0; i < nr_tables; i++) { > + acpi_physical_address table; > + efi_guid_t guid; > + > + config_tables += size; > + > + if (efi_64) { > + efi_config_table_64_t *tbl = (efi_config_table_64_t *)config_tables; > + > + guid = tbl->guid; > + table = tbl->table; > + > + if (!IS_ENABLED(CONFIG_X86_64) && table >> 32) { > + debug_putstr("Error getting RSDP address: EFI config table located above 4GB.\n"); > + return 0; > + } > + } else { > + efi_config_table_32_t *tbl = (efi_config_table_32_t *)config_tables; > + > + guid = tbl->guid; > + table = tbl->table; > + } > + > + if (!(efi_guidcmp(guid, ACPI_TABLE_GUID))) > + rsdp_addr = table; > + else if (!(efi_guidcmp(guid, ACPI_20_TABLE_GUID))) > + return table; > + } > +#endif > + return rsdp_addr; > +} > + It might be worth adding code comments here to tell why we only care about 64bit kexec booting? > +static acpi_physical_address kexec_get_rsdp_addr(void) > +{ > +#ifdef CONFIG_EFI > + struct efi_setup_data *esd; > + efi_system_table_64_t *systab; > + struct efi_info *ei; > + char *sig; > + > + esd = (struct efi_setup_data *) efi_get_kexec_setup_data_addr(); > + if (!esd) > + return 0; > + if (!esd->tables) { > + debug_putstr("Wrong kexec SETUP_EFI data.\n"); > + return 0; > + } > + > + ei = &boot_params->efi_info; > + sig = (char *)&ei->efi_loader_signature; > + if (strncmp(sig, EFI64_LOADER_SIGNATURE, 4)) { > + debug_putstr("Wrong EFI loader signature.\n"); > + return 0; > + } > + > + /* Get systab from boot params. */ > + systab = (efi_system_table_64_t *) (ei->efi_systab | ((__u64)ei->efi_systab_hi << 32)); > + if (!systab) > + error("EFI system table not found."); > + > + return __efi_get_rsdp_addr((unsigned long) esd->tables, systab->nr_tables, sizeof(efi_config_table_64_t), true); > +#else > + return 0; > +#endif > +} > + > +static acpi_physical_address efi_get_rsdp_addr(void) > +{ > +#ifdef CONFIG_EFI > + unsigned long systab, config_tables; > unsigned int nr_tables; > struct efi_info *ei; > bool efi_64; > - int size, i; > + int size; > char *sig; > > ei = &boot_params->efi_info; > @@ -100,37 +189,10 @@ static acpi_physical_address efi_get_rsdp_addr(void) > if (!config_tables) > error("EFI config tables not found."); > > - /* Get EFI tables from systab. */ > - for (i = 0; i < nr_tables; i++) { > - acpi_physical_address table; > - efi_guid_t guid; > - > - config_tables += size; > - > - if (efi_64) { > - efi_config_table_64_t *tbl = (efi_config_table_64_t *)config_tables; > - > - guid = tbl->guid; > - table = tbl->table; > - > - if (!IS_ENABLED(CONFIG_X86_64) && table >> 32) { > - debug_putstr("Error getting RSDP address: EFI config table located above 4GB.\n"); > - return 0; > - } > - } else { > - efi_config_table_32_t *tbl = (efi_config_table_32_t *)config_tables; > - > - guid = tbl->guid; > - table = tbl->table; > - } > - > - if (!(efi_guidcmp(guid, ACPI_TABLE_GUID))) > - rsdp_addr = table; > - else if (!(efi_guidcmp(guid, ACPI_20_TABLE_GUID))) > - return table; > - } > + return __efi_get_rsdp_addr(config_tables, nr_tables, size, efi_64); > +#else > + return 0; > #endif > - return rsdp_addr; > } > > static u8 compute_checksum(u8 *buffer, u32 length) > @@ -221,6 +283,9 @@ acpi_physical_address get_rsdp_addr(void) > pa = boot_params->acpi_rsdp_addr; > > if (!pa) > + pa = kexec_get_rsdp_addr(); > + > + if (!pa) > pa = efi_get_rsdp_addr(); > > if (!pa)