Re: [PATCH] x86/mtrr: Check if fixed MTRRs exist before saving them

From: Andi Kleen
Date: Tue Jan 09 2024 - 23:24:20 EST


On Tue, Jan 09, 2024 at 08:06:26PM +0100, Thomas Gleixner wrote:
> On Fri, Jan 05 2024 at 08:37, Andi Kleen wrote:
> > This one place forgot to check the fixed capability.
>
> What's the consequence of that missing chec

You get a WARN_ON for a WRMSR failing if you don't have the MSR.

> and shouldn't this have a Fixes tag?

It's more an ancient bug back dating back to my tenure in 2007, but here it is:

Fixes: 2b1f6278d77c ("[PATCH] x86: Save the MTRRs of the BSP before")

-Andi