Re: x86/microcode/intel: Division by zero panic in 4.9.79 and 4.4.114

From: Greg KH
Date: Thu Feb 08 2018 - 11:39:52 EST


On Thu, Feb 08, 2018 at 04:25:58PM +0000, Rolf Neugebauer wrote:
> On Thu, Feb 8, 2018 at 2:53 PM, Borislav Petkov <bp@xxxxxxxxx> wrote:
> > On Thu, Feb 08, 2018 at 01:55:48PM +0000, Rolf Neugebauer wrote:
> >> On the 4.4 kernel, 1f161f67a272c ("x86/microcode: Do the family check
> >> first") does not apply cleanly. Looks like it relies on 309aac77768c0
> >> ("x86/microcode: Decrease CPUID use") and 7a93a40be23e5
> >> ("x86/microcode: Remove local vendor variable") as well. These don't
> >> apply cleanly either.
> >
> > It figures. The backporting game is hm, well, a fun one. :-)
> >
> >> Should I just manually backport the functionality of 1f161f67a272c?
> >
> > Yeah, try that first.
>
> Here it is below (same disclaimer about crappy mail client). If Boris
> is fine with the changes, Greg, I can send it properly with "git
> send-email" if needed.

Can you also send this for 4.9? It should need it as well. And at
first glance, it looks good to me.

thanks for doing this,

greg k-h