[PATCH] x86/microcode/intel: replace sync_core() with native_cpuid_reg(eax)

From: Evalds Iodzevics
Date: Mon Apr 20 2020 - 05:00:47 EST


sync_core() always jums past cpuid instruction on 32 bit machines
because data structure boot_cpu_data are not populated so early in boot.

It depends on commit 5dedade6dfa243c130b85d1e4daba6f027805033 for
native_cpuid_reg(eax) definitions

This patch is for 4.4 but also should apply to 4.9

Signed-off-by: Evalds Iodzevics <evalds.iodzevics@xxxxxxxxx>
---
arch/x86/include/asm/microcode_intel.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/microcode_intel.h b/arch/x86/include/asm/microcode_intel.h
index 90343ba50485..92ce9c8a508b 100644
--- a/arch/x86/include/asm/microcode_intel.h
+++ b/arch/x86/include/asm/microcode_intel.h
@@ -60,7 +60,7 @@ static inline u32 intel_get_microcode_revision(void)
native_wrmsrl(MSR_IA32_UCODE_REV, 0);

/* As documented in the SDM: Do a CPUID 1 here */
- sync_core();
+ native_cpuid_eax(1);

/* get the current revision from MSR 0x8B */
native_rdmsr(MSR_IA32_UCODE_REV, dummy, rev);
--
2.17.4