diff options
Diffstat (limited to 'arch/x86/kernel/cpu/microcode/intel.c')
| -rw-r--r-- | arch/x86/kernel/cpu/microcode/intel.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c index 467cf37ea90a..952f1733583e 100644 --- a/arch/x86/kernel/cpu/microcode/intel.c +++ b/arch/x86/kernel/cpu/microcode/intel.c @@ -45,6 +45,208 @@ static struct microcode_intel *intel_ucode_patch; /* last level cache size per core */ static int llc_size_per_core; +/* microcode format is extended from prescott processors */ +struct extended_signature { + unsigned int sig; + unsigned int pf; + unsigned int cksum; +}; + +struct extended_sigtable { + unsigned int count; + unsigned int cksum; + unsigned int reserved[3]; + struct extended_signature sigs[]; +}; + +#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE) +#define EXT_HEADER_SIZE (sizeof(struct extended_sigtable)) +#define EXT_SIGNATURE_SIZE (sizeof(struct extended_signature)) + +static inline unsigned int get_totalsize(struct microcode_header_intel *hdr) +{ + return hdr->datasize ? hdr->totalsize : DEFAULT_UCODE_TOTALSIZE; +} + +static inline unsigned int exttable_size(struct extended_sigtable *et) +{ + return et->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE; +} + +int intel_cpu_collect_info(struct ucode_cpu_info *uci) +{ + unsigned int val[2]; + unsigned int family, model; + struct cpu_signature csig = { 0 }; + unsigned int eax, ebx, ecx, edx; + + memset(uci, 0, sizeof(*uci)); + + eax = 0x00000001; + ecx = 0; + native_cpuid(&eax, &ebx, &ecx, &edx); + csig.sig = eax; + + family = x86_family(eax); + model = x86_model(eax); + + if (model >= 5 || family > 6) { + /* get processor flags from MSR 0x17 */ + native_rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]); + csig.pf = 1 << ((val[1] >> 18) & 7); + } + + csig.rev = intel_get_microcode_revision(); + + uci->cpu_sig = csig; + + return 0; +} +EXPORT_SYMBOL_GPL(intel_cpu_collect_info); + +/* + * Returns 1 if update has been found, 0 otherwise. + */ +int intel_find_matching_signature(void *mc, unsigned int csig, int cpf) +{ + struct microcode_header_intel *mc_hdr = mc; + struct extended_sigtable *ext_hdr; + struct extended_signature *ext_sig; + int i; + + if (intel_cpu_signatures_match(csig, cpf, mc_hdr->sig, mc_hdr->pf)) + return 1; + + /* Look for ext. headers: */ + if (get_totalsize(mc_hdr) <= get_datasize(mc_hdr) + MC_HEADER_SIZE) + return 0; + + ext_hdr = mc + get_datasize(mc_hdr) + MC_HEADER_SIZE; + ext_sig = (void *)ext_hdr + EXT_HEADER_SIZE; + + for (i = 0; i < ext_hdr->count; i++) { + if (intel_cpu_signatures_match(csig, cpf, ext_sig->sig, ext_sig->pf)) + return 1; + ext_sig++; + } + return 0; +} +EXPORT_SYMBOL_GPL(intel_find_matching_signature); + +/** + * intel_microcode_sanity_check() - Sanity check microcode file. + * @mc: Pointer to the microcode file contents. + * @print_err: Display failure reason if true, silent if false. + * @hdr_type: Type of file, i.e. normal microcode file or In Field Scan file. + * Validate if the microcode header type matches with the type + * specified here. + * + * Validate certain header fields and verify if computed checksum matches + * with the one specified in the header. + * + * Return: 0 if the file passes all the checks, -EINVAL if any of the checks + * fail. + */ +int intel_microcode_sanity_check(void *mc, bool print_err, int hdr_type) +{ + unsigned long total_size, data_size, ext_table_size; + struct microcode_header_intel *mc_header = mc; + struct extended_sigtable *ext_header = NULL; + u32 sum, orig_sum, ext_sigcount = 0, i; + struct extended_signature *ext_sig; + + total_size = get_totalsize(mc_header); + data_size = get_datasize(mc_header); + + if (data_size + MC_HEADER_SIZE > total_size) { + if (print_err) + pr_err("Error: bad microcode data file size.\n"); + return -EINVAL; + } + + if (mc_header->ldrver != 1 || mc_header->hdrver != hdr_type) { + if (print_err) + pr_err("Error: invalid/unknown microcode update format. Header type %d\n", + mc_header->hdrver); + return -EINVAL; + } + + ext_table_size = total_size - (MC_HEADER_SIZE + data_size); + if (ext_table_size) { + u32 ext_table_sum = 0; + u32 *ext_tablep; + + if (ext_table_size < EXT_HEADER_SIZE || + ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) { + if (print_err) + pr_err("Error: truncated extended signature table.\n"); + return -EINVAL; + } + + ext_header = mc + MC_HEADER_SIZE + data_size; + if (ext_table_size != exttable_size(ext_header)) { + if (print_err) + pr_err("Error: extended signature table size mismatch.\n"); + return -EFAULT; + } + + ext_sigcount = ext_header->count; + + /* + * Check extended table checksum: the sum of all dwords that + * comprise a valid table must be 0. + */ + ext_tablep = (u32 *)ext_header; + + i = ext_table_size / sizeof(u32); + while (i--) + ext_table_sum += ext_tablep[i]; + + if (ext_table_sum) { + if (print_err) + pr_warn("Bad extended signature table checksum, aborting.\n"); + return -EINVAL; + } + } + + /* + * Calculate the checksum of update data and header. The checksum of + * valid update data and header including the extended signature table + * must be 0. + */ + orig_sum = 0; + i = (MC_HEADER_SIZE + data_size) / sizeof(u32); + while (i--) + orig_sum += ((u32 *)mc)[i]; + + if (orig_sum) { + if (print_err) + pr_err("Bad microcode data checksum, aborting.\n"); + return -EINVAL; + } + + if (!ext_table_size) + return 0; + + /* + * Check extended signature checksum: 0 => valid. + */ + for (i = 0; i < ext_sigcount; i++) { + ext_sig = (void *)ext_header + EXT_HEADER_SIZE + + EXT_SIGNATURE_SIZE * i; + + sum = (mc_header->sig + mc_header->pf + mc_header->cksum) - + (ext_sig->sig + ext_sig->pf + ext_sig->cksum); + if (sum) { + if (print_err) + pr_err("Bad extended signature checksum, aborting.\n"); + return -EINVAL; + } + } + return 0; +} +EXPORT_SYMBOL_GPL(intel_microcode_sanity_check); + /* * Returns 1 if update has been found, 0 otherwise. */ |