Re: [PATCH v9 4/5] x86/xsave: Make XSAVE check the base CPUID features before enabling

From: Thomas Gleixner
Date: Sun Oct 08 2017 - 04:36:52 EST


On Fri, 6 Oct 2017, Andi Kleen wrote:

> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
>
> Before enabling XSAVE, not only check the XSAVE specific CPUID bits,
> but also the base CPUID features of the respective XSAVE feature.
> This allows to disable individual XSAVE states using the existing
> clearcpuid= option, which can be useful for performance testing
> and debugging, and also in general avoids inconsistencies.
>
> v2:
> Add curly brackets (Thomas Gleixner)
> Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>

Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>