This patch introduces new boot option named "efi_fake_mem_mirror". By specifying this parameter, you can mark specific memory as mirrored memory. This is useful for debugging of Address Range Mirroring feature. For example, if you specify "efi_fake_mem_mirror=2G@4G,2G@0x10a0000000", the original (firmware provided) EFI memmap will be updated so that the specified memory regions have EFI_MEMORY_MORE_RELIABLE attribute: <original EFI memmap> efi: mem00: [Boot Data | | | | | | |WB|WT|WC|UC] range=[0x0000000000000000-0x0000000000001000) (0MB) efi: mem01: [Loader Data | | | | | | |WB|WT|WC|UC] range=[0x0000000000001000-0x0000000000002000) (0MB) ... efi: mem35: [Boot Data | | | | | | |WB|WT|WC|UC] range=[0x0000000047ee6000-0x0000000048014000) (1MB) efi: mem36: [Conventional Memory| | | | | | |WB|WT|WC|UC] range=[0x0000000100000000-0x00000020a0000000) (129536MB) efi: mem37: [Reserved |RT| | | | | | | | |UC] range=[0x0000000060000000-0x0000000090000000) (768MB) <updated EFI memmap> efi: mem00: [Boot Data | | | | | | |WB|WT|WC|UC] range=[0x0000000000000000-0x0000000000001000) (0MB) efi: mem01: [Loader Data | | | | | | |WB|WT|WC|UC] range=[0x0000000000001000-0x0000000000002000) (0MB) ... efi: mem35: [Boot Data | | | | | | |WB|WT|WC|UC] range=[0x0000000047ee6000-0x0000000048014000) (1MB) efi: mem36: [Conventional Memory| |MR| | | | |WB|WT|WC|UC] range=[0x0000000100000000-0x0000000180000000) (2048MB) efi: mem37: [Conventional Memory| | | | | | |WB|WT|WC|UC] range=[0x0000000180000000-0x00000010a0000000) (61952MB) efi: mem38: [Conventional Memory| |MR| | | | |WB|WT|WC|UC] range=[0x00000010a0000000-0x0000001120000000) (2048MB) efi: mem39: [Conventional Memory| | | | | | |WB|WT|WC|UC] range=[0x0000001120000000-0x00000020a0000000) (63488MB) efi: mem40: [Reserved |RT| | | | | | | | |UC] range=[0x0000000060000000-0x0000000090000000) (768MB) And you will find that the following message is output: efi: Memory: 4096M/131455M mirrored memory Signed-off-by: Taku Izumi <izumi.taku@xxxxxxxxxxxxxx> --- Documentation/kernel-parameters.txt | 8 ++ arch/x86/include/asm/efi.h | 1 + arch/x86/kernel/setup.c | 4 +- arch/x86/platform/efi/efi.c | 2 +- drivers/firmware/efi/Kconfig | 12 +++ drivers/firmware/efi/Makefile | 1 + drivers/firmware/efi/fake_mem.c | 204 ++++++++++++++++++++++++++++++++++++ include/linux/efi.h | 6 ++ 8 files changed, 236 insertions(+), 2 deletions(-) create mode 100644 drivers/firmware/efi/fake_mem.c diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 1d6f045..0efded6 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1092,6 +1092,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted. you are really sure that your UEFI does sane gc and fulfills the spec otherwise your board may brick. + efi_fake_mem_mirror=nn[KMG]@ss[KMG][,nn[KMG]@ss[KMG],..] [EFI; X86] + Mark specific memory as mirrored memory and update + EFI memory map. + Region of memory to be marked is from ss to ss+nn. + Using this parameter you can do debugging of Address + Range Mirroring feature even if your box doesn't support + it. + eisa_irq_edge= [PARISC,HW] See header of drivers/parisc/eisa.c. diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index 155162e..479fd51 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -93,6 +93,7 @@ extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable); extern int __init efi_memblock_x86_reserve_range(void); extern pgd_t * __init efi_call_phys_prolog(void); extern void __init efi_call_phys_epilog(pgd_t *save_pgd); +extern void __init print_efi_memmap(void); extern void __init efi_unmap_memmap(void); extern void __init efi_memory_uc(u64 addr, unsigned long size); extern void __init efi_map_region(efi_memory_desc_t *md); diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 80f874b..e3ed628 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1104,8 +1104,10 @@ void __init setup_arch(char **cmdline_p) memblock_set_current_limit(ISA_END_ADDRESS); memblock_x86_fill(); - if (efi_enabled(EFI_BOOT)) + if (efi_enabled(EFI_BOOT)) { + efi_fake_memmap(); efi_find_mirror(); + } /* * The EFI specification says that boot service code won't be called diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index e4308fe..eee8068 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -222,7 +222,7 @@ int __init efi_memblock_x86_reserve_range(void) return 0; } -static void __init print_efi_memmap(void) +void __init print_efi_memmap(void) { #ifdef EFI_DEBUG efi_memory_desc_t *md; diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index 54071c1..4fafebe 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -52,6 +52,18 @@ config EFI_RUNTIME_MAP See also Documentation/ABI/testing/sysfs-firmware-efi-runtime-map. +config EFI_FAKE_MEMMAP + bool "Enable EFI Fake memory mirror" + depends on EFI && X86 + default n + help + Saying Y here will enable "efi_fake_mem_miror" boot option. + By specifying this parameter, you can mark specific memory as + mirrored memory by updating original (firmware provided) EFI memmap. + This is useful for debugging of Memory Address Range Mirroring + feature. + + config EFI_PARAMS_FROM_FDT bool help diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index 6fd3da9..c24f005 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -9,3 +9,4 @@ obj-$(CONFIG_UEFI_CPER) += cper.o obj-$(CONFIG_EFI_RUNTIME_MAP) += runtime-map.o obj-$(CONFIG_EFI_RUNTIME_WRAPPERS) += runtime-wrappers.o obj-$(CONFIG_EFI_STUB) += libstub/ +obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c new file mode 100644 index 0000000..2645d4a --- /dev/null +++ b/drivers/firmware/efi/fake_mem.c @@ -0,0 +1,204 @@ +/* + * fake_mem.c + * + * Copyright (C) 2015 FUJITSU LIMITED + * Author: Taku Izumi <izumi.taku@xxxxxxxxxxxxxx> + * + * This code introduces new boot option named "efi_fake_mem_mirror" + * By specifying this parameter, you can mark specific memory as + * mirrored memory by updating original (firmware provided) EFI + * memmap. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, see <http://www.gnu.org/licenses/>. + * + * The full GNU General Public License is included in this distribution in + * the file called "COPYING". + */ + +#include <linux/kernel.h> +#include <linux/efi.h> +#include <linux/init.h> +#include <linux/memblock.h> +#include <linux/types.h> +#include <asm/efi.h> + +#define EFI_MAX_FAKE_MIRROR 8 +static struct range fake_mirrors[EFI_MAX_FAKE_MIRROR]; +static int num_fake_mirror; + +void __init efi_fake_memmap(void) +{ + u64 start, end, m_start, m_end; + int new_nr_map = memmap.nr_map; + efi_memory_desc_t *md; + u64 new_memmap_phy; + void *new_memmap; + void *old, *new; + int i; + + if (!num_fake_mirror) + return; + + /* count up the number of EFI memory descriptor */ + for (old = memmap.map; old < memmap.map_end; old += memmap.desc_size) { + md = old; + start = md->phys_addr; + end = start + (md->num_pages << EFI_PAGE_SHIFT) - 1; + + for (i = 0; i < num_fake_mirror; i++) { + /* mirroring range */ + m_start = fake_mirrors[i].start; + m_end = fake_mirrors[i].end; + + if (m_start <= start) { + /* split into 2 parts */ + if (start < m_end && m_end < end) + new_nr_map++; + } + if (start < m_start && m_start < end) { + /* split into 3 parts */ + if (m_end < end) + new_nr_map += 2; + /* split into 2 parts */ + if (end <= m_end) + new_nr_map++; + } + } + } + + /* allocate memory for new EFI memmap */ + new_memmap_phy = memblock_alloc(memmap.desc_size * new_nr_map, + PAGE_SIZE); + if (!new_memmap_phy) + return; + + /* create new EFI memmap */ + new_memmap = early_memremap(new_memmap_phy, + memmap.desc_size * new_nr_map); + for (old = memmap.map, new = new_memmap; + old < memmap.map_end; + old += memmap.desc_size, new += memmap.desc_size) { + + /* copy original EFI memory descriptor */ + memcpy(new, old, memmap.desc_size); + md = new; + start = md->phys_addr; + end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1; + + for (i = 0; i < num_fake_mirror; i++) { + /* mirroring range */ + m_start = fake_mirrors[i].start; + m_end = fake_mirrors[i].end; + + if (m_start <= start && end <= m_end) + md->attribute |= EFI_MEMORY_MORE_RELIABLE; + + if (m_start <= start && + (start < m_end && m_end < end)) { + /* first part */ + md->attribute |= EFI_MEMORY_MORE_RELIABLE; + md->num_pages = (m_end - md->phys_addr + 1) >> + EFI_PAGE_SHIFT; + /* latter part */ + new += memmap.desc_size; + memcpy(new, old, memmap.desc_size); + md = new; + md->phys_addr = m_end + 1; + md->num_pages = (end - md->phys_addr + 1) >> + EFI_PAGE_SHIFT; + } + + if ((start < m_start && m_start < end) && m_end < end) { + /* first part */ + md->num_pages = (m_start - md->phys_addr) >> + EFI_PAGE_SHIFT; + /* middle part */ + new += memmap.desc_size; + memcpy(new, old, memmap.desc_size); + md = new; + md->attribute |= EFI_MEMORY_MORE_RELIABLE; + md->phys_addr = m_start; + md->num_pages = (m_end - m_start + 1) >> + EFI_PAGE_SHIFT; + /* last part */ + new += memmap.desc_size; + memcpy(new, old, memmap.desc_size); + md = new; + md->phys_addr = m_end + 1; + md->num_pages = (end - m_end) >> + EFI_PAGE_SHIFT; + } + + if ((start < m_start && m_start < end) && + (end <= m_end)) { + /* first part */ + md->num_pages = (m_start - md->phys_addr) >> + EFI_PAGE_SHIFT; + /* latter part */ + new += memmap.desc_size; + memcpy(new, old, memmap.desc_size); + md = new; + md->phys_addr = m_start; + md->num_pages = (end - md->phys_addr + 1) >> + EFI_PAGE_SHIFT; + md->attribute |= EFI_MEMORY_MORE_RELIABLE; + } + } + } + + /* swap into new EFI memmap */ + efi_unmap_memmap(); + memmap.map = new_memmap; + memmap.phys_map = (void *)new_memmap_phy; + memmap.nr_map = new_nr_map; + memmap.map_end = memmap.map + memmap.nr_map * memmap.desc_size; + set_bit(EFI_MEMMAP, &efi.flags); + + /* print new EFI memmap */ + print_efi_memmap(); +} + +static int __init setup_fake_mem_mirror(char *p) +{ + u64 start = 0, mem_size = 0; + int i; + + if (!p) + return -EINVAL; + + while (*p != '\0') { + mem_size = memparse(p, &p); + if (*p == '@') + start = memparse(p+1, &p); + else + break; + + num_fake_mirror = add_range_with_merge(fake_mirrors, + EFI_MAX_FAKE_MIRROR, + num_fake_mirror, + start, + start + mem_size - 1); + if (*p == ',') + p++; + } + + sort_range(fake_mirrors, num_fake_mirror); + + for (i = 0; i < num_fake_mirror; i++) + pr_info("efi_fake_mem_mirror: [mem 0x%016llx-0x%016llx] marked as mirrored memory", + fake_mirrors[i].start, fake_mirrors[i].end); + + return *p == '\0' ? 0 : -EINVAL; +} + +early_param("efi_fake_mem_mirror", setup_fake_mem_mirror); diff --git a/include/linux/efi.h b/include/linux/efi.h index 85ef051..620baec 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -908,6 +908,12 @@ extern struct kobject *efi_kobj; extern int efi_reboot_quirk_mode; extern bool efi_poweroff_required(void); +#ifdef CONFIG_EFI_FAKE_MEMMAP +extern void __init efi_fake_memmap(void); +#else +static inline void efi_fake_memmap(void) { } +#endif + /* Iterate through an efi_memory_map */ #define for_each_efi_memory_desc(m, md) \ for ((md) = (m)->map; \ -- 1.8.3.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. 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