+ Tony.
On Mon, Dec 25, 2017 at 03:49:29PM +0800, Jia Zhang wrote:
> Instead of blacklisting all Broadwell processorsi for running a late
> loading, only BDW-EP (signature 406f1) with the microcode version
> less than 0x0b000021 needs to be blacklisted.
>
> This is documented in the the public documentation #334165 (See the
> item BDF90 for details).
>
> Signed-off-by: Jia Zhang <qianyue...@alibaba-inc.com>
> ---
> arch/x86/kernel/cpu/microcode/intel.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/microcode/intel.c
> b/arch/x86/kernel/cpu/microcode/intel.c
> index 8ccdca6..f80b2dd 100644
> --- a/arch/x86/kernel/cpu/microcode/intel.c
> +++ b/arch/x86/kernel/cpu/microcode/intel.c
> @@ -910,8 +910,15 @@ static bool is_blacklisted(unsigned int cpu)
> {
> struct cpuinfo_x86 *c = &cpu_data(cpu);
>
> - if (c->x86 == 6 && c->x86_model == INTEL_FAM6_BROADWELL_X) {
> - pr_err_once("late loading on model 79 is disabled.\n");
> + /*
> + * The Broadwell-EP processor with the microcode version less
> + * then 0x0b000021 may reault in system hang when running a late
> + * loading. This behavior is documented in item BDF90, #334165
> + * (Intel Xeon Processor E7-8800/4800 v4 Product Family).
> + */
> + if (c->x86 == 6 && c->x86_model == INTEL_FAM6_BROADWELL_X &&
> + c->x86_mask == 0x01 && intel_get_microcode_revision() <
> 0x0b000021U) {
Actually, you shouldn't need to call intel_get_microcode_revision() here
as collect_cpu_info() has done that already and the revision is in
c->microcode
unless you're using the old method through do_microcode_update() and
for that you'll need to call collect_cpu_info() over all CPUs in
microcode_open().
So how do you update your microcode?
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
