diff options
Diffstat (limited to 'drivers/firmware/efi')
| -rw-r--r-- | drivers/firmware/efi/efi.c | 40 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/Makefile | 7 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/unaccepted_memory.c | 2 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/x86-stub.c | 53 | ||||
| -rw-r--r-- | drivers/firmware/efi/unaccepted_memory.c | 64 |
5 files changed, 105 insertions, 61 deletions
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 47ca652f02f6..9d3910d1abe1 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -273,9 +273,13 @@ static __init int efivar_ssdt_load(void) if (status == EFI_NOT_FOUND) { break; } else if (status == EFI_BUFFER_TOO_SMALL) { - name = krealloc(name, name_size, GFP_KERNEL); - if (!name) + efi_char16_t *name_tmp = + krealloc(name, name_size, GFP_KERNEL); + if (!name_tmp) { + kfree(name); return -ENOMEM; + } + name = name_tmp; continue; } @@ -623,6 +627,34 @@ static __init int match_config_table(const efi_guid_t *guid, return 0; } +/** + * reserve_unaccepted - Map and reserve unaccepted configuration table + * @unaccepted: Pointer to unaccepted memory table + * + * memblock_add() makes sure that the table is mapped in direct mapping. During + * normal boot it happens automatically because the table is allocated from + * usable memory. But during crashkernel boot only memory specifically reserved + * for crash scenario is mapped. memblock_add() forces the table to be mapped + * in crashkernel case. + * + * Align the range to the nearest page borders. Ranges smaller than page size + * are not going to be mapped. + * + * memblock_reserve() makes sure that future allocations will not touch the + * table. + */ + +static __init void reserve_unaccepted(struct efi_unaccepted_memory *unaccepted) +{ + phys_addr_t start, size; + + start = PAGE_ALIGN_DOWN(efi.unaccepted); + size = PAGE_ALIGN(sizeof(*unaccepted) + unaccepted->size); + + memblock_add(start, size); + memblock_reserve(start, size); +} + int __init efi_config_parse_tables(const efi_config_table_t *config_tables, int count, const efi_config_table_type_t *arch_tables) @@ -751,11 +783,9 @@ int __init efi_config_parse_tables(const efi_config_table_t *config_tables, unaccepted = early_memremap(efi.unaccepted, sizeof(*unaccepted)); if (unaccepted) { - unsigned long size; if (unaccepted->version == 1) { - size = sizeof(*unaccepted) + unaccepted->size; - memblock_reserve(efi.unaccepted, size); + reserve_unaccepted(unaccepted); } else { efi.unaccepted = EFI_INVALID_TABLE_ADDR; } diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index a1157c2a7170..ef4c12f0877b 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -108,13 +108,6 @@ lib-y := $(patsubst %.o,%.stub.o,$(lib-y)) # https://bugs.llvm.org/show_bug.cgi?id=46480 STUBCOPY_FLAGS-y += --remove-section=.note.gnu.property -# -# For x86, bootloaders like systemd-boot or grub-efi do not zero-initialize the -# .bss section, so the .bss section of the EFI stub needs to be included in the -# .data section of the compressed kernel to ensure initialization. Rename the -# .bss section here so it's easy to pick out in the linker script. -# -STUBCOPY_FLAGS-$(CONFIG_X86) += --rename-section .bss=.bss.efistub,load,alloc STUBCOPY_RELOC-$(CONFIG_X86_32) := R_386_32 STUBCOPY_RELOC-$(CONFIG_X86_64) := R_X86_64_64 diff --git a/drivers/firmware/efi/libstub/unaccepted_memory.c b/drivers/firmware/efi/libstub/unaccepted_memory.c index ca61f4733ea5..9a655f30ba47 100644 --- a/drivers/firmware/efi/libstub/unaccepted_memory.c +++ b/drivers/firmware/efi/libstub/unaccepted_memory.c @@ -62,7 +62,7 @@ efi_status_t allocate_unaccepted_bitmap(__u32 nr_desc, bitmap_size = DIV_ROUND_UP(unaccepted_end - unaccepted_start, EFI_UNACCEPTED_UNIT_SIZE * BITS_PER_BYTE); - status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, + status = efi_bs_call(allocate_pool, EFI_ACPI_RECLAIM_MEMORY, sizeof(*unaccepted_table) + bitmap_size, (void **)&unaccepted_table); if (status != EFI_SUCCESS) { diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c index 2fee52ed335d..1bfdae34df39 100644 --- a/drivers/firmware/efi/libstub/x86-stub.c +++ b/drivers/firmware/efi/libstub/x86-stub.c @@ -449,9 +449,8 @@ void __noreturn efi_stub_entry(efi_handle_t handle, efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg) { - struct boot_params *boot_params; - struct setup_header *hdr; - void *image_base; + static struct boot_params boot_params __page_aligned_bss; + struct setup_header *hdr = &boot_params.hdr; efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID; int options_size = 0; efi_status_t status; @@ -469,30 +468,9 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, efi_exit(handle, status); } - image_base = efi_table_attr(image, image_base); - - status = efi_allocate_pages(sizeof(struct boot_params), - (unsigned long *)&boot_params, ULONG_MAX); - if (status != EFI_SUCCESS) { - efi_err("Failed to allocate lowmem for boot params\n"); - efi_exit(handle, status); - } - - memset(boot_params, 0x0, sizeof(struct boot_params)); - - hdr = &boot_params->hdr; - - /* Copy the setup header from the second sector to boot_params */ - memcpy(&hdr->jump, image_base + 512, - sizeof(struct setup_header) - offsetof(struct setup_header, jump)); - - /* - * Fill out some of the header fields ourselves because the - * EFI firmware loader doesn't load the first sector. - */ + /* Assign the setup_header fields that the kernel actually cares about */ hdr->root_flags = 1; hdr->vid_mode = 0xffff; - hdr->boot_flag = 0xAA55; hdr->type_of_loader = 0x21; @@ -501,25 +479,13 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, if (!cmdline_ptr) goto fail; - efi_set_u64_split((unsigned long)cmdline_ptr, - &hdr->cmd_line_ptr, &boot_params->ext_cmd_line_ptr); - - hdr->ramdisk_image = 0; - hdr->ramdisk_size = 0; - - /* - * Disregard any setup data that was provided by the bootloader: - * setup_data could be pointing anywhere, and we have no way of - * authenticating or validating the payload. - */ - hdr->setup_data = 0; + efi_set_u64_split((unsigned long)cmdline_ptr, &hdr->cmd_line_ptr, + &boot_params.ext_cmd_line_ptr); - efi_stub_entry(handle, sys_table_arg, boot_params); + efi_stub_entry(handle, sys_table_arg, &boot_params); /* not reached */ fail: - efi_free(sizeof(struct boot_params), (unsigned long)boot_params); - efi_exit(handle, status); } @@ -605,11 +571,8 @@ setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_s break; case EFI_UNACCEPTED_MEMORY: - if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY)) { - efi_warn_once( -"The system has unaccepted memory, but kernel does not support it\nConsider enabling CONFIG_UNACCEPTED_MEMORY\n"); + if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY)) continue; - } e820_type = E820_TYPE_RAM; process_unaccepted_memory(d->phys_addr, d->phys_addr + PAGE_SIZE * d->num_pages); @@ -852,6 +815,8 @@ void __noreturn efi_stub_entry(efi_handle_t handle, unsigned long kernel_entry; efi_status_t status; + boot_params_ptr = boot_params; + efi_system_table = sys_table_arg; /* Check if we were booted by the EFI firmware */ if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) diff --git a/drivers/firmware/efi/unaccepted_memory.c b/drivers/firmware/efi/unaccepted_memory.c index 853f7dc3c21d..135278ddaf62 100644 --- a/drivers/firmware/efi/unaccepted_memory.c +++ b/drivers/firmware/efi/unaccepted_memory.c @@ -5,9 +5,17 @@ #include <linux/spinlock.h> #include <asm/unaccepted_memory.h> -/* Protects unaccepted memory bitmap */ +/* Protects unaccepted memory bitmap and accepting_list */ static DEFINE_SPINLOCK(unaccepted_memory_lock); +struct accept_range { + struct list_head list; + unsigned long start; + unsigned long end; +}; + +static LIST_HEAD(accepting_list); + /* * accept_memory() -- Consult bitmap and accept the memory if needed. * @@ -24,6 +32,7 @@ void accept_memory(phys_addr_t start, phys_addr_t end) { struct efi_unaccepted_memory *unaccepted; unsigned long range_start, range_end; + struct accept_range range, *entry; unsigned long flags; u64 unit_size; @@ -78,20 +87,67 @@ void accept_memory(phys_addr_t start, phys_addr_t end) if (end > unaccepted->size * unit_size * BITS_PER_BYTE) end = unaccepted->size * unit_size * BITS_PER_BYTE; - range_start = start / unit_size; - + range.start = start / unit_size; + range.end = DIV_ROUND_UP(end, unit_size); +retry: spin_lock_irqsave(&unaccepted_memory_lock, flags); + + /* + * Check if anybody works on accepting the same range of the memory. + * + * The check is done with unit_size granularity. It is crucial to catch + * all accept requests to the same unit_size block, even if they don't + * overlap on physical address level. + */ + list_for_each_entry(entry, &accepting_list, list) { + if (entry->end < range.start) + continue; + if (entry->start >= range.end) + continue; + + /* + * Somebody else accepting the range. Or at least part of it. + * + * Drop the lock and retry until it is complete. + */ + spin_unlock_irqrestore(&unaccepted_memory_lock, flags); + goto retry; + } + + /* + * Register that the range is about to be accepted. + * Make sure nobody else will accept it. + */ + list_add(&range.list, &accepting_list); + + range_start = range.start; for_each_set_bitrange_from(range_start, range_end, unaccepted->bitmap, - DIV_ROUND_UP(end, unit_size)) { + range.end) { unsigned long phys_start, phys_end; unsigned long len = range_end - range_start; phys_start = range_start * unit_size + unaccepted->phys_base; phys_end = range_end * unit_size + unaccepted->phys_base; + /* + * Keep interrupts disabled until the accept operation is + * complete in order to prevent deadlocks. + * + * Enabling interrupts before calling arch_accept_memory() + * creates an opportunity for an interrupt handler to request + * acceptance for the same memory. The handler will continuously + * spin with interrupts disabled, preventing other task from + * making progress with the acceptance process. + */ + spin_unlock(&unaccepted_memory_lock); + arch_accept_memory(phys_start, phys_end); + + spin_lock(&unaccepted_memory_lock); bitmap_clear(unaccepted->bitmap, range_start, len); } + + list_del(&range.list); spin_unlock_irqrestore(&unaccepted_memory_lock, flags); } |