Re: [patch 2/4] x86/kaiser: Enable PARAVIRT again

From: Juergen Gross
Date: Tue Nov 28 2017 - 01:47:40 EST


On 27/11/17 21:34, Thomas Gleixner wrote:
> XEN_PV paravirtualizes read/write_c3. This does not work with KAISER as the
> CR3 switch from and to user space PGD would require to map the whole XEN_PV
> machinery into both. It's also not clear whether the register space is
> sufficient to do so. All other PV guests use the native implementations and
> are compatible with KAISER.
>
> Add detection for XEN_PV and disable KAISER in the early boot process when
> the kernel is running as a XEN_PV guest.
>
> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

Reviewed-by: Juergen Gross <jgross@xxxxxxxx>


Juergen