Re: [PATCH v2 03/12] x86/pv: switch SWAPGS to ALTERNATIVE

[Thomas Gleixner]

On Fri, Nov 20 2020 at 12:46, Juergen Gross wrote:
> SWAPGS is used only for interrupts coming from user mode or for
> returning to user mode. So there is no reason to use the PARAVIRT
> framework, as it can easily be replaced by an ALTERNATIVE depending
> on X86_FEATURE_XENPV.
>
> There are several instances using the PV-aware SWAPGS macro in paths
> which are never executed in a Xen PV guest. Replace those with the
> plain swapgs instruction. For SWAPGS_UNSAFE_STACK the same applies.
>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> Acked-by: Andy Lutomirski <luto@xxxxxxxxxx>
> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>

Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>