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Diffstat (limited to 'arch/x86/kernel/cpu/microcode/intel.c')
-rw-r--r--arch/x86/kernel/cpu/microcode/intel.c52
1 files changed, 43 insertions, 9 deletions
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index 923054a6b760..32b8e5724f96 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -589,6 +589,23 @@ static int apply_microcode_early(struct ucode_cpu_info *uci, bool early)
if (!mc)
return 0;
+ /*
+ * Save us the MSR write below - which is a particular expensive
+ * operation - when the other hyperthread has updated the microcode
+ * already.
+ */
+ rev = intel_get_microcode_revision();
+ if (rev >= mc->hdr.rev) {
+ uci->cpu_sig.rev = rev;
+ return UCODE_OK;
+ }
+
+ /*
+ * Writeback and invalidate caches before updating microcode to avoid
+ * internal issues depending on what the microcode is updating.
+ */
+ native_wbinvd();
+
/* write microcode via MSR 0x79 */
native_wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
@@ -774,9 +791,9 @@ static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
static enum ucode_state apply_microcode_intel(int cpu)
{
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+ struct cpuinfo_x86 *c = &cpu_data(cpu);
struct microcode_intel *mc;
- struct ucode_cpu_info *uci;
- struct cpuinfo_x86 *c;
static int prev_rev;
u32 rev;
@@ -784,15 +801,32 @@ static enum ucode_state apply_microcode_intel(int cpu)
if (WARN_ON(raw_smp_processor_id() != cpu))
return UCODE_ERROR;
- uci = ucode_cpu_info + cpu;
- mc = uci->mc;
+ /* Look for a newer patch in our cache: */
+ mc = find_patch(uci);
if (!mc) {
- /* Look for a newer patch in our cache: */
- mc = find_patch(uci);
+ mc = uci->mc;
if (!mc)
return UCODE_NFOUND;
}
+ /*
+ * Save us the MSR write below - which is a particular expensive
+ * operation - when the other hyperthread has updated the microcode
+ * already.
+ */
+ rev = intel_get_microcode_revision();
+ if (rev >= mc->hdr.rev) {
+ uci->cpu_sig.rev = rev;
+ c->microcode = rev;
+ return UCODE_OK;
+ }
+
+ /*
+ * Writeback and invalidate caches before updating microcode to avoid
+ * internal issues depending on what the microcode is updating.
+ */
+ native_wbinvd();
+
/* write microcode via MSR 0x79 */
wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
@@ -813,8 +847,6 @@ static enum ucode_state apply_microcode_intel(int cpu)
prev_rev = rev;
}
- c = &cpu_data(cpu);
-
uci->cpu_sig.rev = rev;
c->microcode = rev;
@@ -830,6 +862,7 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
unsigned int leftover = size;
unsigned int curr_mc_size = 0, new_mc_size = 0;
unsigned int csig, cpf;
+ enum ucode_state ret = UCODE_OK;
while (leftover) {
struct microcode_header_intel mc_header;
@@ -871,6 +904,7 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
new_mc = mc;
new_mc_size = mc_size;
mc = NULL; /* trigger new vmalloc */
+ ret = UCODE_NEW;
}
ucode_ptr += mc_size;
@@ -900,7 +934,7 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
cpu, new_rev, uci->cpu_sig.rev);
- return UCODE_OK;
+ return ret;
}
static int get_ucode_fw(void *to, const void *from, size_t n)