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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,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 35A37C65BAE for ; Thu, 13 Dec 2018 20:23:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F0ACC20851 for ; Thu, 13 Dec 2018 20:23:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="UglCcAHg" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F0ACC20851 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=alien8.de 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 S1728743AbeLMUXb (ORCPT ); Thu, 13 Dec 2018 15:23:31 -0500 Received: from mail.skyhub.de ([5.9.137.197]:35386 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726437AbeLMUXa (ORCPT ); Thu, 13 Dec 2018 15:23:30 -0500 Received: from zn.tnic (p200300EC2BCC680084911476902B5E84.dip0.t-ipconnect.de [IPv6:2003:ec:2bcc:6800:8491:1476:902b:5e84]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id C680C1EC08EA; Thu, 13 Dec 2018 21:23:28 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1544732609; 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: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=8blBEzpgaCgxxxZX/oLptrY8jAWxvolU5XO+o2vTI1s=; b=UglCcAHgg+HyXJC+5Wuj4NgdqPJqxkE6xZlwR6nEYKHBoEX+sg4MWjHO7XQX+miXpbBUjD aIYqbmCrI4qhj0nkqirb0/6Akd8UnzJAHPZojaxVwKHUeyTNP59f3igUFJZVeNxPkNtbY4 aYayImfPF1S/6a9Ea/xrpleF3LBQvpk= Date: Thu, 13 Dec 2018 21:23:04 +0100 From: Borislav Petkov To: Chao Fan Cc: linux-kernel@vger.kernel.org, x86@kernel.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, keescook@chromium.org, bhe@redhat.com, msys.mizuma@gmail.com, indou.takao@jp.fujitsu.com, caoj.fnst@cn.fujitsu.com Subject: Re: [PATCH v13 3/6] x86/boot: Introduce efi_get_rsdp_addr() to find RSDP from EFI table Message-ID: <20181213202304.GG25287@zn.tnic> References: <20181212031053.1815-1-fanc.fnst@cn.fujitsu.com> <20181212031053.1815-4-fanc.fnst@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20181212031053.1815-4-fanc.fnst@cn.fujitsu.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 12, 2018 at 11:10:50AM +0800, Chao Fan wrote: > Memory information in SRAT is necessary to fix the conflict between > KASLR and memory-hotremove. So RSDP and SRAT should be parsed. > > When booting form KEXEC/EFI/BIOS, the methods to compute RSDP > are different. When booting from EFI, EFI table points to RSDP. > So parse the EFI table and find the RSDP. > > Signed-off-by: Chao Fan > --- > arch/x86/boot/compressed/acpi.c | 79 +++++++++++++++++++++++++++++++++ > 1 file changed, 79 insertions(+) > > diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c > index cad15686f82c..c96008712ec9 100644 > --- a/arch/x86/boot/compressed/acpi.c > +++ b/arch/x86/boot/compressed/acpi.c > @@ -28,3 +28,82 @@ static acpi_physical_address get_acpi_rsdp(void) > return 0; > #endif > } > + > +/* Search EFI table for RSDP. */ > +static acpi_physical_address efi_get_rsdp_addr(void) > +{ > +#ifdef CONFIG_EFI > + acpi_physical_address rsdp_addr = 0; > + efi_system_table_t *systab; > + struct efi_info *e; > + bool efi_64; > + char *sig; > + int size; > + int i; > + > + e = &boot_params->efi_info; > + sig = (char *)&e->efi_loader_signature; > + > + if (!strncmp(sig, EFI64_LOADER_SIGNATURE, 4)) > + efi_64 = true; > + else if (!strncmp(sig, EFI32_LOADER_SIGNATURE, 4)) > + efi_64 = false; > + else { > + debug_putstr("Wrong EFI loader signature.\n"); > + return 0; > + } Use curly braces for all three branches above. > + > + /* Get systab from boot params. Based on efi_init(). */ > +#ifdef CONFIG_X86_64 > + systab = (efi_system_table_t *)(e->efi_systab | ((__u64)e->efi_systab_hi<<32)); > +#else > + if (e->efi_systab_hi || e->efi_memmap_hi) { > + debug_putstr("Error getting RSDP address: EFI system table located above 4GB.\n"); > + return 0; > + } > + systab = (efi_system_table_t *)e->efi_systab; > +#endif > + > + if (!systab) > + return 0; > + > + /* > + * Get EFI tables from systab. Based on efi_config_init() and > + * efi_config_parse_tables(). > + */ > + size = efi_64 ? sizeof(efi_config_table_64_t) : > + sizeof(efi_config_table_32_t); > + > + for (i = 0; i < systab->nr_tables; i++) { > + void *config_tables; > + unsigned long table; > + efi_guid_t guid; > + > + config_tables = (void *)(systab->tables + size * i); > + if (efi_64) { > + efi_config_table_64_t *tmp_table; > + > + tmp_table = (efi_config_table_64_t *)config_tables; > + guid = tmp_table->guid; > + table = tmp_table->table; > + > + if (!IS_ENABLED(CONFIG_X86_64) && table >> 32) { > + debug_putstr("Error getting RSDP address: EFI system table located above 4GB.\n"); Do s/system/config/ here so that this error message is different from the one above. > + return 0; > + } > + } else { > + efi_config_table_32_t *tmp_table; > + > + tmp_table = (efi_config_table_32_t *)config_tables; > + guid = tmp_table->guid; > + table = tmp_table->table; > + } > + > + if (!(efi_guidcmp(guid, ACPI_TABLE_GUID))) > + rsdp_addr = (acpi_physical_address)table; > + else if (!(efi_guidcmp(guid, ACPI_20_TABLE_GUID))) > + return (acpi_physical_address)table; > + } > + return rsdp_addr; > +#endif } #endif return rsdp_addr; } IOW, you have: static acpi_physical_address efi_get_rsdp_addr(void) { acpi_physical_address rsdp_addr = 0; #ifdef CONFIG_EFI ... #endif return rsdp_addr; } -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.