Re: [PATCH] x86: kvm: use alternatives for VMCALL vs. VMMCALL if kernel text is read-only

From: Borislav Petkov
Date: Tue Sep 23 2014 - 04:27:42 EST


On Tue, Sep 23, 2014 at 10:00:12AM +0200, Paolo Bonzini wrote:
> Il 22/09/2014 21:43, Borislav Petkov ha scritto:
> >> > On x86_64, kernel text mappings are mapped read-only with CONFIG_DEBUG_RODATA.
> > Hmm, that depends on DEBUG_KERNEL.
> >
> > I think you're actually talking about distro kernels which enable
> > CONFIG_DEBUG_RODATA, right?
>
> This is for guest kernels, so it's not necessarily distro kernels.
> Anyone who compiles their kernel with CONFIG_DEBUG_RODATA + PV spinlocks
> would not be able to run it on AMD.

I see. Yeah, so the patch makes sense to me:

Acked-by: Borislav Petkov <bp@xxxxxxx>

Thanks.

--
Regards/Gruss,
Boris.

Sent from a fat crate under my desk. Formatting is fine.
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