diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 5 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/eboot.c | 4 | ||||
| -rw-r--r-- | arch/x86/platform/efi/efi.c | 19 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/arm-stub.c | 4 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/efi-stub-helper.c | 62 | ||||
| -rw-r--r-- | include/linux/efi.h | 2 |
6 files changed, 91 insertions, 5 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 5ae8608..67d7959 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -992,10 +992,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. Format: {"off" | "on" | "skip[mbr]"} efi= [EFI] - Format: { "old_map" } + Format: { "old_map", "nochunk" } 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. efi_no_storage_paranoia [EFI; X86] Using this parameter you can use more than 50% of diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index f277184..f4bdab1 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -1100,6 +1100,10 @@ struct boot_params *make_boot_params(struct efi_config *c) else initrd_addr_max = hdr->initrd_addr_max; + 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=", initrd_addr_max, diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 850da94..a1f745b 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -943,8 +943,23 @@ static int __init parse_efi_cmdline(char *str) if (*str == '=') str++; - if (!strncmp(str, "old_map", 7)) - set_bit(EFI_OLD_MEMMAP, &efi.flags); + while (*str) { + if (!strncmp(str, "old_map", 7)) { + set_bit(EFI_OLD_MEMMAP, &efi.flags); + str += strlen("old_map"); + } + + /* + * Skip any options we don't understand. Presumably + * they apply to the EFI boot stub. + */ + while (*str && *str != ',') + str++; + + /* If we hit a delimiter, skip it */ + if (*str == ',') + str++; + } return 0; } diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c index 480339b..75ee059 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 32d5cca..a920fec 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/include/linux/efi.h b/include/linux/efi.h index 45cb4ff..518779f 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1227,4 +1227,6 @@ 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); + #endif /* _LINUX_EFI_H */ |
