The following commit has been merged into the x86/microcode branch of tip: Commit-ID: 716f380275866350ee44447b3c7c999f39c3178d Gitweb: https://git.kernel.org/tip/716f380275866350ee44447b3c7c999f39c3178d Author: Jithu Joseph <jithu.joseph@xxxxxxxxx> AuthorDate: Wed, 16 Nov 2022 19:59:24 -08:00 Committer: Borislav Petkov <bp@xxxxxxx> CommitterDate: Fri, 18 Nov 2022 21:50:01 +01:00 x86/microcode/intel: Reuse find_matching_signature() IFS uses test images provided by Intel that can be regarded as firmware. An IFS test image carries microcode header with an extended signature table. Reuse find_matching_signature() for verifying if the test image header or the extended signature table indicate whether that image is fit to run on a system. No functional changes. Signed-off-by: Jithu Joseph <jithu.joseph@xxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx> Reviewed-by: Ashok Raj <ashok.raj@xxxxxxxxx> Reviewed-by: Sohil Mehta <sohil.mehta@xxxxxxxxx> Link: https://lore.kernel.org/r/20221117035935.4136738-6-jithu.joseph@xxxxxxxxx --- arch/x86/include/asm/cpu.h | 1 +- arch/x86/kernel/cpu/intel.c | 29 +++++++++++++++++- arch/x86/kernel/cpu/microcode/intel.c | 44 ++++---------------------- 3 files changed, 38 insertions(+), 36 deletions(-) diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h index b472ef7..e853440 100644 --- a/arch/x86/include/asm/cpu.h +++ b/arch/x86/include/asm/cpu.h @@ -95,5 +95,6 @@ static inline bool intel_cpu_signatures_match(unsigned int s1, unsigned int p1, } extern u64 x86_read_arch_cap_msr(void); +int intel_find_matching_signature(void *mc, unsigned int csig, int cpf); #endif /* _ASM_X86_CPU_H */ diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index beb8ca5..c7331ec 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -215,6 +215,35 @@ int intel_cpu_collect_info(struct ucode_cpu_info *uci) } 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); + static void early_init_intel(struct cpuinfo_x86 *c) { u64 misc_enable; diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c index 8c35c70..c77ec1b 100644 --- a/arch/x86/kernel/cpu/microcode/intel.c +++ b/arch/x86/kernel/cpu/microcode/intel.c @@ -48,34 +48,6 @@ static int llc_size_per_core; /* * Returns 1 if update has been found, 0 otherwise. */ -static int 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; -} - -/* - * Returns 1 if update has been found, 0 otherwise. - */ static int has_newer_microcode(void *mc, unsigned int csig, int cpf, int new_rev) { struct microcode_header_intel *mc_hdr = mc; @@ -83,7 +55,7 @@ static int has_newer_microcode(void *mc, unsigned int csig, int cpf, int new_rev if (mc_hdr->rev <= new_rev) return 0; - return find_matching_signature(mc, csig, cpf); + return intel_find_matching_signature(mc, csig, cpf); } static struct ucode_patch *memdup_patch(void *data, unsigned int size) @@ -117,7 +89,7 @@ static void save_microcode_patch(struct ucode_cpu_info *uci, void *data, unsigne sig = mc_saved_hdr->sig; pf = mc_saved_hdr->pf; - if (find_matching_signature(data, sig, pf)) { + if (intel_find_matching_signature(data, sig, pf)) { prev_found = true; if (mc_hdr->rev <= mc_saved_hdr->rev) @@ -149,7 +121,7 @@ static void save_microcode_patch(struct ucode_cpu_info *uci, void *data, unsigne if (!p) return; - if (!find_matching_signature(p->data, uci->cpu_sig.sig, uci->cpu_sig.pf)) + if (!intel_find_matching_signature(p->data, uci->cpu_sig.sig, uci->cpu_sig.pf)) return; /* @@ -286,8 +258,8 @@ scan_microcode(void *data, size_t size, struct ucode_cpu_info *uci, bool save) size -= mc_size; - if (!find_matching_signature(data, uci->cpu_sig.sig, - uci->cpu_sig.pf)) { + if (!intel_find_matching_signature(data, uci->cpu_sig.sig, + uci->cpu_sig.pf)) { data += mc_size; continue; } @@ -652,9 +624,9 @@ static struct microcode_intel *find_patch(struct ucode_cpu_info *uci) if (phdr->rev <= uci->cpu_sig.rev) continue; - if (!find_matching_signature(phdr, - uci->cpu_sig.sig, - uci->cpu_sig.pf)) + if (!intel_find_matching_signature(phdr, + uci->cpu_sig.sig, + uci->cpu_sig.pf)) continue; return iter->data;