Re: [PATCH v2 1/6] x86/speculation: Update Speculation Control microcode blacklist

Thomas Gleixner
2018-02-12T14:32:32Z

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On Mon, 12 Feb 2018, David Woodhouse wrote:

> On Sat, 2018-02-10 at 23:39 +0000, David Woodhouse wrote:
> >
> > --- a/arch/x86/kernel/cpu/intel.c
> > +++ b/arch/x86/kernel/cpu/intel.c
> > @@ -123,8 +123,6 @@ static const struct sku_microcode
> > spectre_bad_microcodes[] = {
> >         { INTEL_FAM6_KABYLAKE_MOBILE,   0x09,   0x84 },
> >         { INTEL_FAM6_SKYLAKE_X,         0x03,   0x0100013e },
> >         { INTEL_FAM6_SKYLAKE_X,         0x04,   0x0200003c },
> > -       { INTEL_FAM6_SKYLAKE_MOBILE,    0x03,   0xc2 },
> > -       { INTEL_FAM6_SKYLAKE_DESKTOP,   0x03,   0xc2 },
> >         { INTEL_FAM6_BROADWELL_CORE,    0x04,   0x28 },
> >         { INTEL_FAM6_BROADWELL_GT3E,    0x01,   0x1b },
> >         { INTEL_FAM6_BROADWELL_XEON_D,  0x02,   0x14 },
>
> Arjan points out that the SKYLAKE_DESKTOP one there is premature. There
> are *two* rows in Intel's table which match that CPUID (506E3).
>
> Only *one* of them ("Skylake H/S") has cleared the 0xC2 microcode for
> use, while the "Skylake E3" line still doesn't approve it. (But doesn't
> explicitly list it in the "STOP deploying" column any more either,
> which it probably should, and might have helped me notice.)
>
> Ingo, Thomas: do you want to drop this patch which is already in
> tip/x86/pti and have a new version with the SKYLAKE_DESKTOP no longer
> removed? Or shall I send an incremental patch to add it back?

Delta patch please.