[PATCH] x86: Avoid using hardcoded number of variable range MTRRs in mtrr_commit()

[Bin Meng]

Hi Simon,

On Tue, Nov 10, 2020 at 12:05 AM Simon Glass <sjg at chromium.org> wrote:
>
> Hi Bin,
>
> On Mon, 9 Nov 2020 at 01:05, Bin Meng <bmeng.cn at gmail.com> wrote:
> >
> > Since commit 29d2d64ed55f ("x86: Add support for more than 8 MTRRs"),
> > the maximum number of variable range MTRRs was increased from 8 to 10,
> > which caused a #GP exception during VESA video driver probe.
> >
> > On the BayTrail platform there are only 8 variable range MTRRs. In
> > mtrr_commit() it still uses MTRR_MAX_COUNT which should have been
> > updated to use dynamically probed number.
> >
> > This fixes the boot failure seen on Intel Minnow Max board.
> >
> > Fixes: 29d2d64ed55f ("x86: Add support for more than 8 MTRRs")
> > Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
> > ---
> >
> >  arch/x86/cpu/mtrr.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
>
> Reviewed-by: Simon Glass <sjg at chromium.org>
>
> I don't actually see the boot failure in my lab, but this looks right to me.

That's weird :)

Regards,
Bin