[patch V4 13/30] x86/microcode/intel: Rework intel_find_matching_signature()

From: Thomas Gleixner
Date: Mon Oct 02 2023 - 08:00:24 EST


Take a cpu_signature argument and work from there. Move the match() helper
next to the callsite as there is no point for having it in a header.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
V2: New patch
---
arch/x86/include/asm/cpu.h | 16 +---------------
arch/x86/kernel/cpu/microcode/intel.c | 31 +++++++++++++++++++------------
drivers/platform/x86/intel/ifs/load.c | 2 +-
3 files changed, 21 insertions(+), 28 deletions(-)

--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -77,22 +77,8 @@ struct cpu_signature;

void intel_collect_cpu_info(struct cpu_signature *sig);

-static inline bool intel_cpu_signatures_match(unsigned int s1, unsigned int p1,
- unsigned int s2, unsigned int p2)
-{
- if (s1 != s2)
- return false;
-
- /* Processor flags are either both 0 ... */
- if (!p1 && !p2)
- return true;
-
- /* ... or they intersect. */
- return p1 & p2;
-}
-
extern u64 x86_read_arch_cap_msr(void);
-int intel_find_matching_signature(void *mc, unsigned int csig, int cpf);
+bool intel_find_matching_signature(void *mc, struct cpu_signature *sig);
int intel_microcode_sanity_check(void *mc, bool print_err, int hdr_type);

extern struct cpumask cpus_stop_mask;
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -82,29 +82,36 @@ void intel_collect_cpu_info(struct cpu_s
}
EXPORT_SYMBOL_GPL(intel_collect_cpu_info);

-/*
- * Returns 1 if update has been found, 0 otherwise.
- */
-int intel_find_matching_signature(void *mc, unsigned int csig, int cpf)
+static inline bool cpu_signatures_match(struct cpu_signature *s1, unsigned int sig2,
+ unsigned int pf2)
+{
+ if (s1->sig != sig2)
+ return false;
+
+ /* Processor flags are either both 0 or they intersect. */
+ return ((!s1->pf && !pf2) || (s1->pf & pf2));
+}
+
+bool intel_find_matching_signature(void *mc, struct cpu_signature *sig)
{
struct microcode_header_intel *mc_hdr = mc;
- struct extended_sigtable *ext_hdr;
struct extended_signature *ext_sig;
+ struct extended_sigtable *ext_hdr;
int i;

- if (intel_cpu_signatures_match(csig, cpf, mc_hdr->sig, mc_hdr->pf))
- return 1;
+ if (cpu_signatures_match(sig, mc_hdr->sig, mc_hdr->pf))
+ return true;

/* Look for ext. headers: */
if (get_totalsize(mc_hdr) <= intel_microcode_get_datasize(mc_hdr) + MC_HEADER_SIZE)
- return 0;
+ return false;

ext_hdr = mc + intel_microcode_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;
+ if (cpu_signatures_match(sig, ext_sig->sig, ext_sig->pf))
+ return true;
ext_sig++;
}
return 0;
@@ -265,7 +272,7 @@ static __init struct microcode_intel *sc
intel_microcode_sanity_check(data, false, MC_HEADER_TYPE_MICROCODE) < 0)
break;

- if (!intel_find_matching_signature(data, uci->cpu_sig.sig, uci->cpu_sig.pf))
+ if (!intel_find_matching_signature(data, &uci->cpu_sig))
continue;

/* Check whether there is newer microcode */
@@ -502,7 +509,7 @@ static enum ucode_state parse_microcode_
if (cur_rev >= mc_header.rev)
continue;

- if (!intel_find_matching_signature(mc, uci->cpu_sig.sig, uci->cpu_sig.pf))
+ if (!intel_find_matching_signature(mc, &uci->cpu_sig))
continue;

kvfree(new_mc);
--- a/drivers/platform/x86/intel/ifs/load.c
+++ b/drivers/platform/x86/intel/ifs/load.c
@@ -242,7 +242,7 @@ static int image_sanity_check(struct dev

intel_collect_cpu_info(&sig);

- if (!intel_find_matching_signature((void *)data, sig.sig, sig.pf)) {
+ if (!intel_find_matching_signature((void *)data, &sig)) {
dev_err(dev, "cpu signature, processor flags not matching\n");
return -EINVAL;
}