Sorry I should remove UTF-8 characters in comment lines. Plz ignore this patch.
Cheers, Jia 在 2017/12/25 下午3:30, Jia Zhang 写道: > 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 <[email protected]> > --- > 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; > } > >
