linux/arch/x86/kernel/cpu/microcode
Borislav Petkov f3e2a51f56 x86/microcode: Use native CPUID to tickle out microcode revision
Intel supplies the microcode revision value in MSR 0x8b
(IA32_BIOS_SIGN_ID) after CPUID(1) has been executed. Execute it each
time before reading that MSR.

It used to do sync_core() which did do CPUID but

  c198b121b1 ("x86/asm: Rewrite sync_core() to use IRET-to-self")

changed the sync_core() implementation so we better make the microcode
loading case explicit, as the SDM documents it.

Reported-and-tested-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20170109114147.5082-3-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-09 23:11:14 +01:00
..
Makefile x86/microcode/intel: Remove intel_lib.c 2016-10-25 12:28:59 +02:00
amd.c x86/microcode/AMD: Use native_cpuid() in load_ucode_amd_bsp() 2016-12-19 10:46:20 +01:00
core.c x86/microcode/AMD: Reload proper initrd start address 2016-12-21 10:50:04 +01:00
intel.c x86/microcode: Use native CPUID to tickle out microcode revision 2017-01-09 23:11:14 +01:00