diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 10d51c2f10d712b179f5e6f67d0b9032bb42b75c..b5e55aab64be0f276336488fc08edbe647f48cdb 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -992,10 +992,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Format: {"off" | "on" | "skip[mbr]"} efi= [EFI] - Format: { "old_map" } + Format: { "old_map", "nochunk", "noruntime" } old_map [X86-64]: switch to the old ioremap-based EFI runtime services mapping. 32-bit still uses this one by default. + nochunk: disable reading files in "chunks" in the EFI + boot stub, as chunking can cause problems with some + firmware implementations. + noruntime : disable EFI runtime services support efi_no_storage_paranoia [EFI; X86] Using this parameter you can use more than 50% of @@ -2166,7 +2170,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nodsp [SH] Disable hardware DSP at boot time. - noefi [X86] Disable EFI runtime services support. + noefi Disable EFI runtime services support. noexec [IA-64] diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index 03aaa99e1ea00a3d4caf79d27cea669d857a9090..95c49ebc660dd85864981bfdfa13bc1f5066d76f 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -89,7 +89,8 @@ static int __init uefi_init(void) */ if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) { pr_err("System table signature incorrect\n"); - return -EINVAL; + retval = -EINVAL; + goto out; } if ((efi.systab->hdr.revision >> 16) < 2) pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n", @@ -103,6 +104,7 @@ static int __init uefi_init(void) for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i) vendor[i] = c16[i]; vendor[i] = '\0'; + early_memunmap(c16, sizeof(vendor)); } pr_info("EFI v%u.%.02u by %s\n", @@ -113,29 +115,11 @@ static int __init uefi_init(void) if (retval == 0) set_bit(EFI_CONFIG_TABLES, &efi.flags); - early_memunmap(c16, sizeof(vendor)); +out: early_memunmap(efi.systab, sizeof(efi_system_table_t)); - return retval; } -static __initdata char memory_type_name[][32] = { - {"Reserved"}, - {"Loader Code"}, - {"Loader Data"}, - {"Boot Code"}, - {"Boot Data"}, - {"Runtime Code"}, - {"Runtime Data"}, - {"Conventional Memory"}, - {"Unusable Memory"}, - {"ACPI Reclaim Memory"}, - {"ACPI Memory NVS"}, - {"Memory Mapped I/O"}, - {"MMIO Port Space"}, - {"PAL Code"}, -}; - /* * Return true for RAM regions we want to permanently reserve. */ @@ -166,10 +150,13 @@ static __init void reserve_regions(void) paddr = md->phys_addr; npages = md->num_pages; - if (uefi_debug) - pr_info(" 0x%012llx-0x%012llx [%s]", + if (uefi_debug) { + char buf[64]; + + pr_info(" 0x%012llx-0x%012llx %s", paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1, - memory_type_name[md->type]); + efi_md_typeattr_format(buf, sizeof(buf), md)); + } memrange_efi_to_native(&paddr, &npages); size = npages << PAGE_SHIFT; @@ -393,11 +380,16 @@ static int __init arm64_enter_virtual_mode(void) return -1; } - pr_info("Remapping and enabling EFI services.\n"); - - /* replace early memmap mapping with permanent mapping */ mapsize = memmap.map_end - memmap.map; early_memunmap(memmap.map, mapsize); + + if (efi_runtime_disabled()) { + pr_info("EFI runtime services will be disabled.\n"); + return -1; + } + + pr_info("Remapping and enabling EFI services.\n"); + /* replace early memmap mapping with permanent mapping */ memmap.map = (__force void *)ioremap_cache((phys_addr_t)memmap.phys_map, mapsize); memmap.map_end = memmap.map + mapsize; diff --git a/arch/ia64/kernel/efi.c b/arch/ia64/kernel/efi.c index 741b99c1a0b1483b153be8823ae681a141d71bf5..c52d7540dc05f4c8ca324e0f6f9ce118f9570d71 100644 --- a/arch/ia64/kernel/efi.c +++ b/arch/ia64/kernel/efi.c @@ -568,6 +568,7 @@ efi_init (void) { const char *unit; unsigned long size; + char buf[64]; md = p; size = md->num_pages << EFI_PAGE_SHIFT; @@ -586,9 +587,10 @@ efi_init (void) unit = "KB"; } - printk("mem%02d: type=%2u, attr=0x%016lx, " + printk("mem%02d: %s " "range=[0x%016lx-0x%016lx) (%4lu%s)\n", - i, md->type, md->attribute, md->phys_addr, + i, efi_md_typeattr_format(buf, sizeof(buf), md), + md->phys_addr, md->phys_addr + efi_md_size(md), size, unit); } } diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index de8eebd6f67c825b3f013f7bc20a228b807c181f..1acf605a646dd87830f22694991142415c6ff351 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -330,8 +330,10 @@ __setup_efi_pci32(efi_pci_io_protocol_32 *pci, struct pci_setup_rom **__rom) size = pci->romsize + sizeof(*rom); status = efi_call_early(allocate_pool, EFI_LOADER_DATA, size, &rom); - if (status != EFI_SUCCESS) + if (status != EFI_SUCCESS) { + efi_printk(sys_table, "Failed to alloc mem for rom\n"); return status; + } memset(rom, 0, sizeof(*rom)); @@ -344,14 +346,18 @@ __setup_efi_pci32(efi_pci_io_protocol_32 *pci, struct pci_setup_rom **__rom) status = efi_early->call(pci->pci.read, pci, EfiPciIoWidthUint16, PCI_VENDOR_ID, 1, &(rom->vendor)); - if (status != EFI_SUCCESS) + if (status != EFI_SUCCESS) { + efi_printk(sys_table, "Failed to read rom->vendor\n"); goto free_struct; + } status = efi_early->call(pci->pci.read, pci, EfiPciIoWidthUint16, PCI_DEVICE_ID, 1, &(rom->devid)); - if (status != EFI_SUCCESS) + if (status != EFI_SUCCESS) { + efi_printk(sys_table, "Failed to read rom->devid\n"); goto free_struct; + } status = efi_early->call(pci->get_location, pci, &(rom->segment), &(rom->bus), &(rom->device), &(rom->function)); @@ -432,8 +438,10 @@ __setup_efi_pci64(efi_pci_io_protocol_64 *pci, struct pci_setup_rom **__rom) size = pci->romsize + sizeof(*rom); status = efi_call_early(allocate_pool, EFI_LOADER_DATA, size, &rom); - if (status != EFI_SUCCESS) + if (status != EFI_SUCCESS) { + efi_printk(sys_table, "Failed to alloc mem for rom\n"); return status; + } rom->data.type = SETUP_PCI; rom->data.len = size - sizeof(struct setup_data); @@ -444,14 +452,18 @@ __setup_efi_pci64(efi_pci_io_protocol_64 *pci, struct pci_setup_rom **__rom) status = efi_early->call(pci->pci.read, pci, EfiPciIoWidthUint16, PCI_VENDOR_ID, 1, &(rom->vendor)); - if (status != EFI_SUCCESS) + if (status != EFI_SUCCESS) { + efi_printk(sys_table, "Failed to read rom->vendor\n"); goto free_struct; + } status = efi_early->call(pci->pci.read, pci, EfiPciIoWidthUint16, PCI_DEVICE_ID, 1, &(rom->devid)); - if (status != EFI_SUCCESS) + if (status != EFI_SUCCESS) { + efi_printk(sys_table, "Failed to read rom->devid\n"); goto free_struct; + } status = efi_early->call(pci->get_location, pci, &(rom->segment), &(rom->bus), &(rom->device), &(rom->function)); @@ -538,8 +550,10 @@ static void setup_efi_pci(struct boot_params *params) EFI_LOADER_DATA, size, (void **)&pci_handle); - if (status != EFI_SUCCESS) + if (status != EFI_SUCCESS) { + efi_printk(sys_table, "Failed to alloc mem for pci_handle\n"); return; + } status = efi_call_early(locate_handle, EFI_LOCATE_BY_PROTOCOL, &pci_proto, @@ -1105,6 +1119,10 @@ struct boot_params *make_boot_params(struct efi_config *c) memset(sdt, 0, sizeof(*sdt)); + status = efi_parse_options(cmdline_ptr); + if (status != EFI_SUCCESS) + goto fail2; + status = handle_cmdline_files(sys_table, image, (char *)(unsigned long)hdr->cmd_line_ptr, "initrd=", hdr->initrd_addr_max, diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index 0ec241ede5a256327f9a578ac2d61d0def83b2c5..9b11757975d025045b747097e95ad0009293a8a2 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -81,24 +81,23 @@ extern u64 asmlinkage efi_call(void *fp, ...); */ #define __efi_call_virt(f, args...) efi_call_virt(f, args) -extern void __iomem *efi_ioremap(unsigned long addr, unsigned long size, - u32 type, u64 attribute); +extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size, + u32 type, u64 attribute); #endif /* CONFIG_X86_32 */ -extern int add_efi_memmap; extern struct efi_scratch efi_scratch; -extern void efi_set_executable(efi_memory_desc_t *md, bool executable); -extern int efi_memblock_x86_reserve_range(void); -extern void efi_call_phys_prelog(void); -extern void efi_call_phys_epilog(void); -extern void efi_unmap_memmap(void); -extern void efi_memory_uc(u64 addr, unsigned long size); +extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable); +extern int __init efi_memblock_x86_reserve_range(void); +extern void __init efi_call_phys_prolog(void); +extern void __init efi_call_phys_epilog(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); extern void __init efi_map_region_fixed(efi_memory_desc_t *md); extern void efi_sync_low_kernel_mappings(void); -extern int efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages); -extern void efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages); +extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages); +extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages); extern void __init old_map_region(efi_memory_desc_t *md); extern void __init runtime_code_page_mkexec(void); extern void __init efi_runtime_mkexec(void); @@ -162,16 +161,6 @@ static inline efi_status_t efi_thunk_set_virtual_address_map( extern bool efi_reboot_required(void); #else -/* - * IF EFI is not configured, have the EFI calls return -ENOSYS. - */ -#define efi_call0(_f) (-ENOSYS) -#define efi_call1(_f, _a1) (-ENOSYS) -#define efi_call2(_f, _a1, _a2) (-ENOSYS) -#define efi_call3(_f, _a1, _a2, _a3) (-ENOSYS) -#define efi_call4(_f, _a1, _a2, _a3, _a4) (-ENOSYS) -#define efi_call5(_f, _a1, _a2, _a3, _a4, _a5) (-ENOSYS) -#define efi_call6(_f, _a1, _a2, _a3, _a4, _a5, _a6) (-ENOSYS) static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {} static inline bool efi_reboot_required(void) { diff --git a/arch/x86/platform/efi/efi-bgrt.c b/arch/x86/platform/efi/efi-bgrt.c index f15103dff4b43f04e16ff8bbd59354435aec4cb7..d143d216d52bec69b912128d88c3283cd0122c6c 100644 --- a/arch/x86/platform/efi/efi-bgrt.c +++ b/arch/x86/platform/efi/efi-bgrt.c @@ -40,20 +40,40 @@ void __init efi_bgrt_init(void) if (ACPI_FAILURE(status)) return; - if (bgrt_tab->header.length < sizeof(*bgrt_tab)) + if (bgrt_tab->header.length < sizeof(*bgrt_tab)) { + pr_err("Ignoring BGRT: invalid length %u (expected %zu)\n", + bgrt_tab->header.length, sizeof(*bgrt_tab)); return; - if (bgrt_tab->version != 1 || bgrt_tab->status != 1) + } + if (bgrt_tab->version != 1) { + pr_err("Ignoring BGRT: invalid version %u (expected 1)\n", + bgrt_tab->version); + return; + } + if (bgrt_tab->status != 1) { + pr_err("Ignoring BGRT: invalid status %u (expected 1)\n", + bgrt_tab->status); + return; + } + if (bgrt_tab->image_type != 0) { + pr_err("Ignoring BGRT: invalid image type %u (expected 0)\n", + bgrt_tab->image_type); return; - if (bgrt_tab->image_type != 0 || !bgrt_tab->image_address) + } + if (!bgrt_tab->image_address) { + pr_err("Ignoring BGRT: null image address\n"); return; + } image = efi_lookup_mapped_addr(bgrt_tab->image_address); if (!image) { image = early_memremap(bgrt_tab->image_address, sizeof(bmp_header)); ioremapped = true; - if (!image) + if (!image) { + pr_err("Ignoring BGRT: failed to map image header memory\n"); return; + } } memcpy_fromio(&bmp_header, image, sizeof(bmp_header)); @@ -61,14 +81,18 @@ void __init efi_bgrt_init(void) early_iounmap(image, sizeof(bmp_header)); bgrt_image_size = bmp_header.size; - bgrt_image = kmalloc(bgrt_image_size, GFP_KERNEL); - if (!bgrt_image) + bgrt_image = kmalloc(bgrt_image_size, GFP_KERNEL | __GFP_NOWARN); + if (!bgrt_image) { + pr_err("Ignoring BGRT: failed to allocate memory for image (wanted %zu bytes)\n", + bgrt_image_size); return; + } if (ioremapped) { image = early_memremap(bgrt_tab->image_address, bmp_header.size); if (!image) { + pr_err("Ignoring BGRT: failed to map image memory\n"); kfree(bgrt_image); bgrt_image = NULL; return; diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 850da94fef305f65e20bdb52370cc75c1420fd5c..dbc8627a5cdf6d569a5f69cbea05ebac924d2279 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -70,17 +70,7 @@ static efi_config_table_type_t arch_tables[] __initdata = { u64 efi_setup; /* efi setup_data physical address */ -static bool disable_runtime __initdata = false; -static int __init setup_noefi(char *arg) -{ - disable_runtime = true; - return 0; -} -early_param("noefi", setup_noefi); - -int add_efi_memmap; -EXPORT_SYMBOL(add_efi_memmap); - +static int add_efi_memmap __initdata; static int __init setup_add_efi_memmap(char *arg) { add_efi_memmap = 1; @@ -96,7 +86,7 @@ static efi_status_t __init phys_efi_set_virtual_address_map( { efi_status_t status; - efi_call_phys_prelog(); + efi_call_phys_prolog(); status = efi_call_phys(efi_phys.set_virtual_address_map, memory_map_size, descriptor_size, descriptor_version, virtual_map); @@ -210,9 +200,12 @@ static void __init print_efi_memmap(void) for (p = memmap.map, i = 0; p < memmap.map_end; p += memmap.desc_size, i++) { + char buf[64]; + md = p; - pr_info("mem%02u: type=%u, attr=0x%llx, range=[0x%016llx-0x%016llx) (%lluMB)\n", - i, md->type, md->attribute, md->phys_addr, + pr_info("mem%02u: %s range=[0x%016llx-0x%016llx) (%lluMB)\n", + i, efi_md_typeattr_format(buf, sizeof(buf), md), + md->phys_addr, md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT), (md->num_pages >> (20 - EFI_PAGE_SHIFT))); } @@ -344,9 +337,9 @@ static int __init efi_runtime_init32(void) } /* - * We will only need *early* access to the following two - * EFI runtime services before set_virtual_address_map - * is invoked. + * We will only need *early* access to the SetVirtualAddressMap + * EFI runtime service. All other runtime services will be called + * via the virtual mapping. */ efi_phys.set_virtual_address_map = (efi_set_virtual_address_map_t *) @@ -368,9 +361,9 @@ static int __init efi_runtime_init64(void) } /* - * We will only need *early* access to the following two - * EFI runtime services before set_virtual_address_map - * is invoked. + * We will only need *early* access to the SetVirtualAddressMap + * EFI runtime service. All other runtime services will be called + * via the virtual mapping. */ efi_phys.set_virtual_address_map = (efi_set_virtual_address_map_t *) @@ -492,7 +485,7 @@ void __init efi_init(void) if (!efi_runtime_supported()) pr_info("No EFI runtime due to 32/64-bit mismatch with kernel\n"); else { - if (disable_runtime || efi_runtime_init()) + if (efi_runtime_disabled() || efi_runtime_init()) return; } if (efi_memmap_init()) @@ -537,7 +530,7 @@ void __init runtime_code_page_mkexec(void) } } -void efi_memory_uc(u64 addr, unsigned long size) +void __init efi_memory_uc(u64 addr, unsigned long size) { unsigned long page_shift = 1UL << EFI_PAGE_SHIFT; u64 npages; @@ -732,6 +725,7 @@ static void __init kexec_enter_virtual_mode(void) */ if (!efi_is_native()) { efi_unmap_memmap(); + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); return; } @@ -805,6 +799,7 @@ static void __init __efi_enter_virtual_mode(void) new_memmap = efi_map_regions(&count, &pg_shift); if (!new_memmap) { pr_err("Error reallocating memory, EFI runtime non-functional!\n"); + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); return; } @@ -812,8 +807,10 @@ static void __init __efi_enter_virtual_mode(void) BUG_ON(!efi.systab); - if (efi_setup_page_tables(__pa(new_memmap), 1 << pg_shift)) + if (efi_setup_page_tables(__pa(new_memmap), 1 << pg_shift)) { + clear_bit(EFI_RUNTIME_SERVICES, &efi.flags); return; + } efi_sync_low_kernel_mappings(); efi_dump_pagetable(); @@ -938,14 +935,11 @@ u64 efi_mem_attributes(unsigned long phys_addr) return 0; } -static int __init parse_efi_cmdline(char *str) +static int __init arch_parse_efi_cmdline(char *str) { - if (*str == '=') - str++; - - if (!strncmp(str, "old_map", 7)) + if (parse_option_str(str, "old_map")) set_bit(EFI_OLD_MEMMAP, &efi.flags); return 0; } -early_param("efi", parse_efi_cmdline); +early_param("efi", arch_parse_efi_cmdline); diff --git a/arch/x86/platform/efi/efi_32.c b/arch/x86/platform/efi/efi_32.c index 9ee3491e31fbab7f6643462395d31c6f9f36f1b4..40e7cda529365133b50bab8745d9995c47557d53 100644 --- a/arch/x86/platform/efi/efi_32.c +++ b/arch/x86/platform/efi/efi_32.c @@ -33,7 +33,7 @@ /* * To make EFI call EFI runtime service in physical addressing mode we need - * prelog/epilog before/after the invocation to disable interrupt, to + * prolog/epilog before/after the invocation to disable interrupt, to * claim EFI runtime service handler exclusively and to duplicate a memory in * low memory space say 0 - 3G. */ @@ -41,11 +41,13 @@ static unsigned long efi_rt_eflags; void efi_sync_low_kernel_mappings(void) {} void __init efi_dump_pagetable(void) {} -int efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) +int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) { return 0; } -void efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages) {} +void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages) +{ +} void __init efi_map_region(efi_memory_desc_t *md) { @@ -55,7 +57,7 @@ void __init efi_map_region(efi_memory_desc_t *md) void __init efi_map_region_fixed(efi_memory_desc_t *md) {} void __init parse_efi_setup(u64 phys_addr, u32 data_len) {} -void efi_call_phys_prelog(void) +void __init efi_call_phys_prolog(void) { struct desc_ptr gdt_descr; @@ -69,7 +71,7 @@ void efi_call_phys_prelog(void) load_gdt(&gdt_descr); } -void efi_call_phys_epilog(void) +void __init efi_call_phys_epilog(void) { struct desc_ptr gdt_descr; diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 290d397e1dd9125e408a1ee140fe4d3ced51a33d..35aecb6042fbc1dcf938e8779a0f60961d76aeb6 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -79,7 +79,7 @@ static void __init early_code_mapping_set_exec(int executable) } } -void __init efi_call_phys_prelog(void) +void __init efi_call_phys_prolog(void) { unsigned long vaddress; int pgd; @@ -139,7 +139,7 @@ void efi_sync_low_kernel_mappings(void) sizeof(pgd_t) * num_pgds); } -int efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) +int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) { unsigned long text; struct page *page; @@ -192,7 +192,7 @@ int efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) return 0; } -void efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages) +void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages) { pgd_t *pgd = (pgd_t *)__va(real_mode_header->trampoline_pgd); diff --git a/arch/x86/platform/efi/efi_stub_32.S b/arch/x86/platform/efi/efi_stub_32.S index fbe66e626c09f437da6110bec5c080ef39e6bf95..040192b50d0209b46b64e2607b0e41fe2bb0123b 100644 --- a/arch/x86/platform/efi/efi_stub_32.S +++ b/arch/x86/platform/efi/efi_stub_32.S @@ -27,13 +27,13 @@ ENTRY(efi_call_phys) * set to 0x0010, DS and SS have been set to 0x0018. In EFI, I found * the values of these registers are the same. And, the corresponding * GDT entries are identical. So I will do nothing about segment reg - * and GDT, but change GDT base register in prelog and epilog. + * and GDT, but change GDT base register in prolog and epilog. */ /* * 1. Now I am running with EIP = + PAGE_OFFSET. * But to make it smoothly switch from virtual mode to flat mode. - * The mapping of lower virtual memory has been created in prelog and + * The mapping of lower virtual memory has been created in prolog and * epilog. */ movl $1f, %edx diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 64ecbb501c5080df5e36b90dd73501b7dac881d4..8590099ac148aa767484236cbdd576b421c85303 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -41,6 +41,28 @@ struct efi __read_mostly efi = { }; EXPORT_SYMBOL(efi); +static bool disable_runtime; +static int __init setup_noefi(char *arg) +{ + disable_runtime = true; + return 0; +} +early_param("noefi", setup_noefi); + +bool efi_runtime_disabled(void) +{ + return disable_runtime; +} + +static int __init parse_efi_cmdline(char *str) +{ + if (parse_option_str(str, "noruntime")) + disable_runtime = true; + + return 0; +} +early_param("efi", parse_efi_cmdline); + static struct kobject *efi_kobj; static struct kobject *efivars_kobj; @@ -423,3 +445,60 @@ int __init efi_get_fdt_params(struct efi_fdt_params *params, int verbose) return ret; } #endif /* CONFIG_EFI_PARAMS_FROM_FDT */ + +static __initdata char memory_type_name[][20] = { + "Reserved", + "Loader Code", + "Loader Data", + "Boot Code", + "Boot Data", + "Runtime Code", + "Runtime Data", + "Conventional Memory", + "Unusable Memory", + "ACPI Reclaim Memory", + "ACPI Memory NVS", + "Memory Mapped I/O", + "MMIO Port Space", + "PAL Code" +}; + +char * __init efi_md_typeattr_format(char *buf, size_t size, + const efi_memory_desc_t *md) +{ + char *pos; + int type_len; + u64 attr; + + pos = buf; + if (md->type >= ARRAY_SIZE(memory_type_name)) + type_len = snprintf(pos, size, "[type=%u", md->type); + else + type_len = snprintf(pos, size, "[%-*s", + (int)(sizeof(memory_type_name[0]) - 1), + memory_type_name[md->type]); + if (type_len >= size) + return buf; + + pos += type_len; + size -= type_len; + + attr = md->attribute; + if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | + EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_WP | + EFI_MEMORY_RP | EFI_MEMORY_XP | EFI_MEMORY_RUNTIME)) + snprintf(pos, size, "|attr=0x%016llx]", + (unsigned long long)attr); + else + snprintf(pos, size, "|%3s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", + attr & EFI_MEMORY_RUNTIME ? "RUN" : "", + attr & EFI_MEMORY_XP ? "XP" : "", + attr & EFI_MEMORY_RP ? "RP" : "", + attr & EFI_MEMORY_WP ? "WP" : "", + attr & EFI_MEMORY_UCE ? "UCE" : "", + attr & EFI_MEMORY_WB ? "WB" : "", + attr & EFI_MEMORY_WT ? "WT" : "", + attr & EFI_MEMORY_WC ? "WC" : "", + attr & EFI_MEMORY_UC ? "UC" : ""); + return buf; +} diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c index 480339b6b110db047848d33c010c7c217ddd04b2..75ee05964cbc460fc0b6686a50a1f664fac8c0e7 100644 --- a/drivers/firmware/efi/libstub/arm-stub.c +++ b/drivers/firmware/efi/libstub/arm-stub.c @@ -226,6 +226,10 @@ unsigned long __init efi_entry(void *handle, efi_system_table_t *sys_table, goto fail_free_image; } + status = efi_parse_options(cmdline_ptr); + if (status != EFI_SUCCESS) + pr_efi_err(sys_table, "Failed to parse EFI cmdline options\n"); + /* * Unauthenticated device tree data is a security hazard, so * ignore 'dtb=' unless UEFI Secure Boot is disabled. diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c index 32d5cca30f496d88594de5f74d0d1de9bce5057d..a920fec8fe8856132191e5b08b95c227310078f8 100644 --- a/drivers/firmware/efi/libstub/efi-stub-helper.c +++ b/drivers/firmware/efi/libstub/efi-stub-helper.c @@ -15,8 +15,23 @@ #include "efistub.h" +/* + * Some firmware implementations have problems reading files in one go. + * A read chunk size of 1MB seems to work for most platforms. + * + * Unfortunately, reading files in chunks triggers *other* bugs on some + * platforms, so we provide a way to disable this workaround, which can + * be done by passing "efi=nochunk" on the EFI boot stub command line. + * + * If you experience issues with initrd images being corrupt it's worth + * trying efi=nochunk, but chunking is enabled by default because there + * are far more machines that require the workaround than those that + * break with it enabled. + */ #define EFI_READ_CHUNK_SIZE (1024 * 1024) +static unsigned long __chunk_size = EFI_READ_CHUNK_SIZE; + struct file_info { efi_file_handle_t *handle; u64 size; @@ -281,6 +296,49 @@ void efi_free(efi_system_table_t *sys_table_arg, unsigned long size, efi_call_early(free_pages, addr, nr_pages); } +/* + * Parse the ASCII string 'cmdline' for EFI options, denoted by the efi= + * option, e.g. efi=nochunk. + * + * It should be noted that efi= is parsed in two very different + * environments, first in the early boot environment of the EFI boot + * stub, and subsequently during the kernel boot. + */ +efi_status_t efi_parse_options(char *cmdline) +{ + char *str; + + /* + * If no EFI parameters were specified on the cmdline we've got + * nothing to do. + */ + str = strstr(cmdline, "efi="); + if (!str) + return EFI_SUCCESS; + + /* Skip ahead to first argument */ + str += strlen("efi="); + + /* + * Remember, because efi= is also used by the kernel we need to + * skip over arguments we don't understand. + */ + while (*str) { + if (!strncmp(str, "nochunk", 7)) { + str += strlen("nochunk"); + __chunk_size = -1UL; + } + + /* Group words together, delimited by "," */ + while (*str && *str != ',') + str++; + + if (*str == ',') + str++; + } + + return EFI_SUCCESS; +} /* * Check the cmdline for a LILO-style file= arguments. @@ -423,8 +481,8 @@ efi_status_t handle_cmdline_files(efi_system_table_t *sys_table_arg, size = files[j].size; while (size) { unsigned long chunksize; - if (size > EFI_READ_CHUNK_SIZE) - chunksize = EFI_READ_CHUNK_SIZE; + if (size > __chunk_size) + chunksize = __chunk_size; else chunksize = size; diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c index 10daa4bbb25833321ffa15ed72e11b327100aa3c..228bbf91046137de619a4f8f89825e8ccc34b5ab 100644 --- a/drivers/firmware/efi/runtime-wrappers.c +++ b/drivers/firmware/efi/runtime-wrappers.c @@ -14,10 +14,79 @@ * This file is released under the GPLv2. */ +#include #include -#include /* spinlock_t */ +#include +#include #include +/* + * According to section 7.1 of the UEFI spec, Runtime Services are not fully + * reentrant, and there are particular combinations of calls that need to be + * serialized. (source: UEFI Specification v2.4A) + * + * Table 31. Rules for Reentry Into Runtime Services + * +------------------------------------+-------------------------------+ + * | If previous call is busy in | Forbidden to call | + * +------------------------------------+-------------------------------+ + * | Any | SetVirtualAddressMap() | + * +------------------------------------+-------------------------------+ + * | ConvertPointer() | ConvertPointer() | + * +------------------------------------+-------------------------------+ + * | SetVariable() | ResetSystem() | + * | UpdateCapsule() | | + * | SetTime() | | + * | SetWakeupTime() | | + * | GetNextHighMonotonicCount() | | + * +------------------------------------+-------------------------------+ + * | GetVariable() | GetVariable() | + * | GetNextVariableName() | GetNextVariableName() | + * | SetVariable() | SetVariable() | + * | QueryVariableInfo() | QueryVariableInfo() | + * | UpdateCapsule() | UpdateCapsule() | + * | QueryCapsuleCapabilities() | QueryCapsuleCapabilities() | + * | GetNextHighMonotonicCount() | GetNextHighMonotonicCount() | + * +------------------------------------+-------------------------------+ + * | GetTime() | GetTime() | + * | SetTime() | SetTime() | + * | GetWakeupTime() | GetWakeupTime() | + * | SetWakeupTime() | SetWakeupTime() | + * +------------------------------------+-------------------------------+ + * + * Due to the fact that the EFI pstore may write to the variable store in + * interrupt context, we need to use a spinlock for at least the groups that + * contain SetVariable() and QueryVariableInfo(). That leaves little else, as + * none of the remaining functions are actually ever called at runtime. + * So let's just use a single spinlock to serialize all Runtime Services calls. + */ +static DEFINE_SPINLOCK(efi_runtime_lock); + +/* + * Some runtime services calls can be reentrant under NMI, even if the table + * above says they are not. (source: UEFI Specification v2.4A) + * + * Table 32. Functions that may be called after Machine Check, INIT and NMI + * +----------------------------+------------------------------------------+ + * | Function | Called after Machine Check, INIT and NMI | + * +----------------------------+------------------------------------------+ + * | GetTime() | Yes, even if previously busy. | + * | GetVariable() | Yes, even if previously busy | + * | GetNextVariableName() | Yes, even if previously busy | + * | QueryVariableInfo() | Yes, even if previously busy | + * | SetVariable() | Yes, even if previously busy | + * | UpdateCapsule() | Yes, even if previously busy | + * | QueryCapsuleCapabilities() | Yes, even if previously busy | + * | ResetSystem() | Yes, even if previously busy | + * +----------------------------+------------------------------------------+ + * + * In order to prevent deadlocks under NMI, the wrappers for these functions + * may only grab the efi_runtime_lock or rtc_lock spinlocks if !efi_in_nmi(). + * However, not all of the services listed are reachable through NMI code paths, + * so the the special handling as suggested by the UEFI spec is only implemented + * for QueryVariableInfo() and SetVariable(), as these can be reached in NMI + * context through efi_pstore_write(). + */ + /* * As per commit ef68c8f87ed1 ("x86: Serialize EFI time accesses on rtc_lock"), * the EFI specification requires that callers of the time related runtime @@ -32,7 +101,9 @@ static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc) efi_status_t status; spin_lock_irqsave(&rtc_lock, flags); + spin_lock(&efi_runtime_lock); status = efi_call_virt(get_time, tm, tc); + spin_unlock(&efi_runtime_lock); spin_unlock_irqrestore(&rtc_lock, flags); return status; } @@ -43,7 +114,9 @@ static efi_status_t virt_efi_set_time(efi_time_t *tm) efi_status_t status; spin_lock_irqsave(&rtc_lock, flags); + spin_lock(&efi_runtime_lock); status = efi_call_virt(set_time, tm); + spin_unlock(&efi_runtime_lock); spin_unlock_irqrestore(&rtc_lock, flags); return status; } @@ -56,7 +129,9 @@ static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled, efi_status_t status; spin_lock_irqsave(&rtc_lock, flags); + spin_lock(&efi_runtime_lock); status = efi_call_virt(get_wakeup_time, enabled, pending, tm); + spin_unlock(&efi_runtime_lock); spin_unlock_irqrestore(&rtc_lock, flags); return status; } @@ -67,7 +142,9 @@ static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm) efi_status_t status; spin_lock_irqsave(&rtc_lock, flags); + spin_lock(&efi_runtime_lock); status = efi_call_virt(set_wakeup_time, enabled, tm); + spin_unlock(&efi_runtime_lock); spin_unlock_irqrestore(&rtc_lock, flags); return status; } @@ -78,14 +155,27 @@ static efi_status_t virt_efi_get_variable(efi_char16_t *name, unsigned long *data_size, void *data) { - return efi_call_virt(get_variable, name, vendor, attr, data_size, data); + unsigned long flags; + efi_status_t status; + + spin_lock_irqsave(&efi_runtime_lock, flags); + status = efi_call_virt(get_variable, name, vendor, attr, data_size, + data); + spin_unlock_irqrestore(&efi_runtime_lock, flags); + return status; } static efi_status_t virt_efi_get_next_variable(unsigned long *name_size, efi_char16_t *name, efi_guid_t *vendor) { - return efi_call_virt(get_next_variable, name_size, name, vendor); + unsigned long flags; + efi_status_t status; + + spin_lock_irqsave(&efi_runtime_lock, flags); + status = efi_call_virt(get_next_variable, name_size, name, vendor); + spin_unlock_irqrestore(&efi_runtime_lock, flags); + return status; } static efi_status_t virt_efi_set_variable(efi_char16_t *name, @@ -94,24 +184,61 @@ static efi_status_t virt_efi_set_variable(efi_char16_t *name, unsigned long data_size, void *data) { - return efi_call_virt(set_variable, name, vendor, attr, data_size, data); + unsigned long flags; + efi_status_t status; + + spin_lock_irqsave(&efi_runtime_lock, flags); + status = efi_call_virt(set_variable, name, vendor, attr, data_size, + data); + spin_unlock_irqrestore(&efi_runtime_lock, flags); + return status; } +static efi_status_t +virt_efi_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor, + u32 attr, unsigned long data_size, + void *data) +{ + unsigned long flags; + efi_status_t status; + + if (!spin_trylock_irqsave(&efi_runtime_lock, flags)) + return EFI_NOT_READY; + + status = efi_call_virt(set_variable, name, vendor, attr, data_size, + data); + spin_unlock_irqrestore(&efi_runtime_lock, flags); + return status; +} + + static efi_status_t virt_efi_query_variable_info(u32 attr, u64 *storage_space, u64 *remaining_space, u64 *max_variable_size) { + unsigned long flags; + efi_status_t status; + if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) return EFI_UNSUPPORTED; - return efi_call_virt(query_variable_info, attr, storage_space, - remaining_space, max_variable_size); + spin_lock_irqsave(&efi_runtime_lock, flags); + status = efi_call_virt(query_variable_info, attr, storage_space, + remaining_space, max_variable_size); + spin_unlock_irqrestore(&efi_runtime_lock, flags); + return status; } static efi_status_t virt_efi_get_next_high_mono_count(u32 *count) { - return efi_call_virt(get_next_high_mono_count, count); + unsigned long flags; + efi_status_t status; + + spin_lock_irqsave(&efi_runtime_lock, flags); + status = efi_call_virt(get_next_high_mono_count, count); + spin_unlock_irqrestore(&efi_runtime_lock, flags); + return status; } static void virt_efi_reset_system(int reset_type, @@ -119,17 +246,27 @@ static void virt_efi_reset_system(int reset_type, unsigned long data_size, efi_char16_t *data) { + unsigned long flags; + + spin_lock_irqsave(&efi_runtime_lock, flags); __efi_call_virt(reset_system, reset_type, status, data_size, data); + spin_unlock_irqrestore(&efi_runtime_lock, flags); } static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules, unsigned long count, unsigned long sg_list) { + unsigned long flags; + efi_status_t status; + if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) return EFI_UNSUPPORTED; - return efi_call_virt(update_capsule, capsules, count, sg_list); + spin_lock_irqsave(&efi_runtime_lock, flags); + status = efi_call_virt(update_capsule, capsules, count, sg_list); + spin_unlock_irqrestore(&efi_runtime_lock, flags); + return status; } static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules, @@ -137,11 +274,17 @@ static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules, u64 *max_size, int *reset_type) { + unsigned long flags; + efi_status_t status; + if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) return EFI_UNSUPPORTED; - return efi_call_virt(query_capsule_caps, capsules, count, max_size, - reset_type); + spin_lock_irqsave(&efi_runtime_lock, flags); + status = efi_call_virt(query_capsule_caps, capsules, count, max_size, + reset_type); + spin_unlock_irqrestore(&efi_runtime_lock, flags); + return status; } void efi_native_runtime_setup(void) @@ -153,6 +296,7 @@ void efi_native_runtime_setup(void) efi.get_variable = virt_efi_get_variable; efi.get_next_variable = virt_efi_get_next_variable; efi.set_variable = virt_efi_set_variable; + efi.set_variable_nonblocking = virt_efi_set_variable_nonblocking; efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count; efi.reset_system = virt_efi_reset_system; efi.query_variable_info = virt_efi_query_variable_info; diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c index 5abe943e34042df45d8d1f643b0334e6ceb19748..70a0fb10517f94ea5b28bada280d9935f0693cc7 100644 --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -321,11 +321,11 @@ static unsigned long var_name_strnsize(efi_char16_t *variable_name, * Print a warning when duplicate EFI variables are encountered and * disable the sysfs workqueue since the firmware is buggy. */ -static void dup_variable_bug(efi_char16_t *s16, efi_guid_t *vendor_guid, +static void dup_variable_bug(efi_char16_t *str16, efi_guid_t *vendor_guid, unsigned long len16) { size_t i, len8 = len16 / sizeof(efi_char16_t); - char *s8; + char *str8; /* * Disable the workqueue since the algorithm it uses for @@ -334,16 +334,16 @@ static void dup_variable_bug(efi_char16_t *s16, efi_guid_t *vendor_guid, */ efivar_wq_enabled = false; - s8 = kzalloc(len8, GFP_KERNEL); - if (!s8) + str8 = kzalloc(len8, GFP_KERNEL); + if (!str8) return; for (i = 0; i < len8; i++) - s8[i] = s16[i]; + str8[i] = str16[i]; printk(KERN_WARNING "efivars: duplicate variable: %s-%pUl\n", - s8, vendor_guid); - kfree(s8); + str8, vendor_guid); + kfree(str8); } /** @@ -595,6 +595,39 @@ int efivar_entry_set(struct efivar_entry *entry, u32 attributes, } EXPORT_SYMBOL_GPL(efivar_entry_set); +/* + * efivar_entry_set_nonblocking - call set_variable_nonblocking() + * + * This function is guaranteed to not block and is suitable for calling + * from crash/panic handlers. + * + * Crucially, this function will not block if it cannot acquire + * __efivars->lock. Instead, it returns -EBUSY. + */ +static int +efivar_entry_set_nonblocking(efi_char16_t *name, efi_guid_t vendor, + u32 attributes, unsigned long size, void *data) +{ + const struct efivar_operations *ops = __efivars->ops; + unsigned long flags; + efi_status_t status; + + if (!spin_trylock_irqsave(&__efivars->lock, flags)) + return -EBUSY; + + status = check_var_size(attributes, size + ucs2_strsize(name, 1024)); + if (status != EFI_SUCCESS) { + spin_unlock_irqrestore(&__efivars->lock, flags); + return -ENOSPC; + } + + status = ops->set_variable_nonblocking(name, &vendor, attributes, + size, data); + + spin_unlock_irqrestore(&__efivars->lock, flags); + return efi_status_to_err(status); +} + /** * efivar_entry_set_safe - call set_variable() if enough space in firmware * @name: buffer containing the variable name @@ -622,6 +655,20 @@ int efivar_entry_set_safe(efi_char16_t *name, efi_guid_t vendor, u32 attributes, if (!ops->query_variable_store) return -ENOSYS; + /* + * If the EFI variable backend provides a non-blocking + * ->set_variable() operation and we're in a context where we + * cannot block, then we need to use it to avoid live-locks, + * since the implication is that the regular ->set_variable() + * will block. + * + * If no ->set_variable_nonblocking() is provided then + * ->set_variable() is assumed to be non-blocking. + */ + if (!block && ops->set_variable_nonblocking) + return efivar_entry_set_nonblocking(name, vendor, attributes, + size, data); + if (!block) { if (!spin_trylock_irqsave(&__efivars->lock, flags)) return -EBUSY; diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index a168e96142b95001f5ece9585cfff8a07c1bb489..54ef393b0def14aa415a1789ba3e1ee51c94bc5f 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -806,7 +806,7 @@ config RTC_DRV_DA9063 config RTC_DRV_EFI tristate "EFI RTC" - depends on EFI + depends on EFI && !X86 help If you say yes here you will get support for the EFI Real Time Clock. diff --git a/drivers/rtc/rtc-efi.c b/drivers/rtc/rtc-efi.c index c384fec6d173b2f051c2871e78fb0128ac65782c..53b589dc34ebe7a7ee6a6466322515b8f62a1f10 100644 --- a/drivers/rtc/rtc-efi.c +++ b/drivers/rtc/rtc-efi.c @@ -236,3 +236,4 @@ MODULE_ALIAS("platform:rtc-efi"); MODULE_AUTHOR("dann frazier "); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("EFI RTC driver"); +MODULE_ALIAS("platform:rtc-efi"); diff --git a/include/linux/efi.h b/include/linux/efi.h index 45cb4ffdea621281aa2068676b9cad9115e48c65..0949f9c7e872e7877e64d13341b5973d5a4ebd21 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -92,6 +92,7 @@ typedef struct { #define EFI_MEMORY_WC ((u64)0x0000000000000002ULL) /* write-coalescing */ #define EFI_MEMORY_WT ((u64)0x0000000000000004ULL) /* write-through */ #define EFI_MEMORY_WB ((u64)0x0000000000000008ULL) /* write-back */ +#define EFI_MEMORY_UCE ((u64)0x0000000000000010ULL) /* uncached, exported */ #define EFI_MEMORY_WP ((u64)0x0000000000001000ULL) /* write-protect */ #define EFI_MEMORY_RP ((u64)0x0000000000002000ULL) /* read-protect */ #define EFI_MEMORY_XP ((u64)0x0000000000004000ULL) /* execute-protect */ @@ -502,6 +503,10 @@ typedef efi_status_t efi_get_next_variable_t (unsigned long *name_size, efi_char typedef efi_status_t efi_set_variable_t (efi_char16_t *name, efi_guid_t *vendor, u32 attr, unsigned long data_size, void *data); +typedef efi_status_t +efi_set_variable_nonblocking_t(efi_char16_t *name, efi_guid_t *vendor, + u32 attr, unsigned long data_size, void *data); + typedef efi_status_t efi_get_next_high_mono_count_t (u32 *count); typedef void efi_reset_system_t (int reset_type, efi_status_t status, unsigned long data_size, efi_char16_t *data); @@ -821,6 +826,7 @@ extern struct efi { efi_get_variable_t *get_variable; efi_get_next_variable_t *get_next_variable; efi_set_variable_t *set_variable; + efi_set_variable_nonblocking_t *set_variable_nonblocking; efi_query_variable_info_t *query_variable_info; efi_update_capsule_t *update_capsule; efi_query_capsule_caps_t *query_capsule_caps; @@ -886,6 +892,13 @@ extern bool efi_poweroff_required(void); (md) <= (efi_memory_desc_t *)((m)->map_end - (m)->desc_size); \ (md) = (void *)(md) + (m)->desc_size) +/* + * Format an EFI memory descriptor's type and attributes to a user-provided + * character buffer, as per snprintf(), and return the buffer. + */ +char * __init efi_md_typeattr_format(char *buf, size_t size, + const efi_memory_desc_t *md); + /** * efi_range_is_wc - check the WC bit on an address range * @start: starting kvirt address @@ -1034,6 +1047,7 @@ struct efivar_operations { efi_get_variable_t *get_variable; efi_get_next_variable_t *get_next_variable; efi_set_variable_t *set_variable; + efi_set_variable_nonblocking_t *set_variable_nonblocking; efi_query_variable_store_t *query_variable_store; }; @@ -1227,4 +1241,7 @@ efi_status_t handle_cmdline_files(efi_system_table_t *sys_table_arg, unsigned long *load_addr, unsigned long *load_size); +efi_status_t efi_parse_options(char *cmdline); + +bool efi_runtime_disabled(void); #endif /* _LINUX_EFI_H */ diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 95624bed87ef6f8c389e78621b628240bf408208..f66427ef0628caaf433f5b3f17a6644d599938c3 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -407,6 +407,7 @@ int vsscanf(const char *, const char *, va_list); extern int get_option(char **str, int *pint); extern char *get_options(const char *str, int nints, int *ints); extern unsigned long long memparse(const char *ptr, char **retptr); +extern bool parse_option_str(const char *str, const char *option); extern int core_kernel_text(unsigned long addr); extern int core_kernel_data(unsigned long addr); diff --git a/lib/cmdline.c b/lib/cmdline.c index 76a712e6e20e3d0480d9f338565079a9089560dd..8f13cf73c2ecf916c203ef7e963d250a113c3dee 100644 --- a/lib/cmdline.c +++ b/lib/cmdline.c @@ -160,3 +160,32 @@ unsigned long long memparse(const char *ptr, char **retptr) return ret; } EXPORT_SYMBOL(memparse); + +/** + * parse_option_str - Parse a string and check an option is set or not + * @str: String to be parsed + * @option: option name + * + * This function parses a string containing a comma-separated list of + * strings like a=b,c. + * + * Return true if there's such option in the string, or return false. + */ +bool parse_option_str(const char *str, const char *option) +{ + while (*str) { + if (!strncmp(str, option, strlen(option))) { + str += strlen(option); + if (!*str || *str == ',') + return true; + } + + while (*str && *str != ',') + str++; + + if (*str == ',') + str++; + } + + return false; +}