Messages in this thread Patch in this message | | | From | "Jia Zhang" <> | Subject | [PATCH] x86/microcode/intel: Blacklist the specific BDW-EP for late loading | Date | Mon, 25 Dec 2017 15:30:44 +0800 |
| |
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.zj@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..5495369 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) { + pr_err_once("late loading on model 79 (sig 64f1) is disabled.\n"); return true; } -- 1.8.3.1
| |