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 30C10C04EB9 for ; Fri, 30 Nov 2018 01:25:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E092D2086B for ; Fri, 30 Nov 2018 01:25:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E092D2086B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=cn.fujitsu.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 S1727169AbeK3Mcl (ORCPT ); Fri, 30 Nov 2018 07:32:41 -0500 Received: from mail.cn.fujitsu.com ([183.91.158.132]:1821 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726393AbeK3Mcl (ORCPT ); Fri, 30 Nov 2018 07:32:41 -0500 X-IronPort-AV: E=Sophos;i="5.56,296,1539619200"; d="scan'208";a="48850056" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 30 Nov 2018 09:25:08 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id D599B4B734A7; Fri, 30 Nov 2018 09:25:08 +0800 (CST) Received: from localhost.localdomain (10.167.225.56) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.408.0; Fri, 30 Nov 2018 09:25:09 +0800 Date: Fri, 30 Nov 2018 09:24:54 +0800 From: Chao Fan To: Masayoshi Mizuma CC: , , , , , , , , , Subject: Re: [PATCH v12 4/5] x86/boot: Parse SRAT table from RSDP and store immovable memory Message-ID: <20181130012454.GB1527@localhost.localdomain> References: <20181129081631.11139-1-fanc.fnst@cn.fujitsu.com> <20181129081631.11139-5-fanc.fnst@cn.fujitsu.com> <20181129175520.xcmj3bv4yhdr7kk3@gabell> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20181129175520.xcmj3bv4yhdr7kk3@gabell> User-Agent: Mutt/1.10.1 (2018-07-13) X-Originating-IP: [10.167.225.56] X-yoursite-MailScanner-ID: D599B4B734A7.ACE76 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: fanc.fnst@cn.fujitsu.com Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 29, 2018 at 12:55:21PM -0500, Masayoshi Mizuma wrote: >On Thu, Nov 29, 2018 at 04:16:30PM +0800, Chao Fan wrote: >> To fix the conflict between KASLR and memory-hotremove, SRAT table >> should be parsed by RSDP pointer, then find the immovable >> memory regions and store them in an array called immovable_mem[]. >> The array called immovable_mem[] will extern to KASLR, then >> KASLR will avoid to extract kernel to these regions. >> >> Add 'CONFIG_EARLY_PARSE_RSDP' which depends on RANDOMIZE_BASE && >> MEMORY_HOTREMOVE, cause only when both KASLR and memory-hotremove >> are enabled, RSDP needs to be parsed in compressed period. >> >> Signed-off-by: Chao Fan >> --- >> arch/x86/Kconfig | 10 +++ >> arch/x86/boot/compressed/Makefile | 2 + >> arch/x86/boot/compressed/acpitb.c | 125 ++++++++++++++++++++++++++++++ >> arch/x86/boot/compressed/kaslr.c | 4 - >> arch/x86/boot/compressed/misc.h | 20 +++++ >> 5 files changed, 157 insertions(+), 4 deletions(-) >> >> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig >> index a29d49ef4d56..bc775968557b 100644 >> --- a/arch/x86/Kconfig >> +++ b/arch/x86/Kconfig >> @@ -2146,6 +2146,16 @@ config X86_NEED_RELOCS >> def_bool y >> depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) >> > >> +config CONFIG_EARLY_PARSE_RSDP > >config EARLY_PARSE_RSDP > >> + bool "Parse RSDP pointer on compressed period for KASLR" >> + def_bool n > >Should be def_bool y? I will change it to y. >It is better to enable EARLY_PARSE_RSDP by default if >RANDOMIZE_BASE and MEMORY_HOTREMOVE are enabled. > >> + depends on RANDOMIZE_BASE && MEMORY_HOTREMOVE >> + help >> + This option parses RSDP pointer in compressed period. Works >> + for KASLR to get memory information by SRAT table and choose >> + immovable memory to extract kernel. >> + Say Y if you want to use both KASLR and memory-hotremove. >> + >> config PHYSICAL_ALIGN >> hex "Alignment value to which kernel should be aligned" >> default "0x200000" >> diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile >> index 466f66c8a7f8..4cbfb58bf083 100644 >> --- a/arch/x86/boot/compressed/Makefile >> +++ b/arch/x86/boot/compressed/Makefile >> @@ -84,6 +84,8 @@ ifdef CONFIG_X86_64 >> vmlinux-objs-y += $(obj)/pgtable_64.o >> endif >> >> +vmlinux-objs-$(CONFIG_EARLY_PARSE_RSDP) += $(obj)/acpitb.o >> + >> $(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone >> >> vmlinux-objs-$(CONFIG_EFI_STUB) += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o \ >> diff --git a/arch/x86/boot/compressed/acpitb.c b/arch/x86/boot/compressed/acpitb.c >> index 82d27c4b8978..023b33d0cd3b 100644 >> --- a/arch/x86/boot/compressed/acpitb.c >> +++ b/arch/x86/boot/compressed/acpitb.c >> @@ -195,3 +195,128 @@ static acpi_physical_address bios_get_rsdp_addr(void) >> return (acpi_physical_address)address; >> } >> } >> + >> +/* Used to determine RSDP table, based on acpi_os_get_root_pointer(). */ >> +static acpi_physical_address get_rsdp_addr(void) >> +{ >> + acpi_physical_address pa = 0; >> + >> + pa = get_acpi_rsdp(); >> + >> + if (!pa) >> + pa = efi_get_rsdp_addr(); >> + >> + if (!pa) >> + pa = bios_get_rsdp_addr(); >> + >> + return pa; >> +} >> + >> +/* Compute SRAT table from RSDP. */ >> +static struct acpi_table_header *get_acpi_srat_table(void) >> +{ >> + acpi_physical_address acpi_table; >> + acpi_physical_address root_table; >> + struct acpi_table_header *header; >> + struct acpi_table_rsdp *rsdp; >> + int num_entries; >> + char arg[10]; >> + u8 *entry; >> + u32 size; >> + u32 len; >> + >> + rsdp = (struct acpi_table_rsdp *)get_rsdp_addr(); >> + if (!rsdp) >> + return NULL; >> + >> + /* Get RSDT or XSDT from RSDP. */ > >> + if (!(cmdline_find_option("acpi", arg, sizeof(arg)) == 4 && >> + !strncmp(arg, "rsdt", 4)) && >> + rsdp->xsdt_physical_address && >> + rsdp->revision > 1) { >> + root_table = rsdp->xsdt_physical_address; >> + size = ACPI_XSDT_ENTRY_SIZE; >> + } else { >> + root_table = rsdp->rsdt_physical_address; >> + size = ACPI_RSDT_ENTRY_SIZE; >> + } >> + >> + /* Get ACPI root table from RSDT or XSDT.*/ >> + header = (struct acpi_table_header *)root_table; >> + if (!header) >> + return NULL; >> + >> + len = header->length; >> + num_entries = (u32)((len - sizeof(struct acpi_table_header)) / size); > >> + if (num_entries > MAX_ACPI_SIG) >> + return NULL; > >I think this check isn't needed... > >> + >> + entry = ACPI_ADD_PTR(u8, header, sizeof(struct acpi_table_header)); >> + >> + while (num_entries--) { >> + u64 address64; >> + >> + if (size == ACPI_RSDT_ENTRY_SIZE) >> + acpi_table = ((acpi_physical_address) >> + (*ACPI_CAST_PTR(u32, entry))); >> + else { >> + *(u64 *)(void *)&address64 = *(u64 *)(void *)entry; >> + acpi_table = (acpi_physical_address) address64; >> + } >> + >> + if (acpi_table) { >> + header = (struct acpi_table_header *)acpi_table; >> + >> + if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_SRAT)) >> + return header; >> + } >> + entry += size; >> + } >> + return NULL; >> +} >> + >> +/* >> + * According to ACPI table, filter the immovable memory regions >> + * and store them in immovable_mem[]. >> + */ >> +void get_immovable_mem(void) >> +{ >> + struct acpi_table_header *table_header; >> + struct acpi_subtable_header *table; >> + struct acpi_srat_mem_affinity *ma; >> + unsigned long table_end; >> + char arg[10]; >> + int i = 0; >> + >> + if (cmdline_find_option("acpi", arg, sizeof(arg)) == 3 && >> + !strncmp(arg, "off", 3)) >> + return; >> + >> + table_header = get_acpi_srat_table(); >> + if (!table_header) >> + return; >> + >> + table_end = (unsigned long)table_header + table_header->length; >> + table = (struct acpi_subtable_header *) >> + ((unsigned long)table_header + sizeof(struct acpi_table_srat)); >> + >> + while (((unsigned long)table) + >> + sizeof(struct acpi_subtable_header) < table_end) { >> + if (table->type == ACPI_SRAT_TYPE_MEMORY_AFFINITY) { >> + ma = (struct acpi_srat_mem_affinity *)table; >> + if (!(ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE)) { >> + immovable_mem[i].start = ma->base_address; >> + immovable_mem[i].size = ma->length; >> + i++; >> + } >> + >> + if (i >= MAX_NUMNODES*2) { >> + debug_putstr("Too many immovable memory regions, aborting.\n"); >> + return; >> + } >> + } >> + table = (struct acpi_subtable_header *) >> + ((unsigned long)table + table->length); >> + } >> + num_immovable_mem = i; >> +} >> diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c >> index 9ed9709d9947..b251572e77af 100644 >> --- a/arch/x86/boot/compressed/kaslr.c >> +++ b/arch/x86/boot/compressed/kaslr.c >> @@ -87,10 +87,6 @@ static unsigned long get_boot_seed(void) >> #define KASLR_COMPRESSED_BOOT >> #include "../../lib/kaslr.c" >> >> -struct mem_vector { >> - unsigned long long start; >> - unsigned long long size; >> -}; >> >> /* Only supporting at most 4 unusable memmap regions with kaslr */ >> #define MAX_MEMMAP_REGIONS 4 >> diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h >> index 809c31effa4b..d94e2a419c13 100644 >> --- a/arch/x86/boot/compressed/misc.h >> +++ b/arch/x86/boot/compressed/misc.h >> @@ -77,6 +77,11 @@ void choose_random_location(unsigned long input, >> unsigned long *output, >> unsigned long output_size, >> unsigned long *virt_addr); >> +struct mem_vector { >> + unsigned long long start; >> + unsigned long long size; >> +}; >> + >> /* cpuflags.c */ >> bool has_cpuflag(int flag); >> #else >> @@ -118,5 +123,20 @@ void set_sev_encryption_mask(void); >> #endif >> >> /* acpitb.c */ >> +#ifdef CONFIG_RANDOMIZE_BASE >> +/* Store the amount of immovable memory regions */ >> +int num_immovable_mem; >> +#endif >> + >> +#ifdef CONFIG_EARLY_PARSE_RSDP >> +void get_immovable_mem(void); > >> +/* There are 72 kinds of ACPI_SIG in head file of ACPI. */ >> +#define MAX_ACPI_SIG 72 > >The 72 isn't the specification of ACPI, right? So the number Yes, it's from ACPI code, include/acpi/actbl*h. Boris said there should be a check for the num_entries, I didn't get a good idea, so I use the max number to check it. So do you have some advice? Thanks, Chao Fan >of SIG may increase and decrease in the future. >This macro and the check I commented above isn't needed... > >Thanks, >Masa > >> +#else >> +static void get_immovable_mem(void) >> +{ >> +} >> +#endif >> + >> #define BOOT_STRING >> extern int kstrtoull(const char *s, unsigned int base, unsigned long long *res); >> -- >> 2.19.1 >> >> >> > >