Re: [PATCH] x86, kvm: Add MSR_AMD64_BU_CFG2 to the list of ignoredMSRs

[Gleb Natapov]

On Wed, Feb 13, 2013 at 12:55:26PM +0100, Borislav Petkov wrote:
> On Wed, Feb 13, 2013 at 01:47:47PM +0200, Gleb Natapov wrote:
> > On Wed, Feb 13, 2013 at 12:42:41PM +0100, Borislav Petkov wrote:
> > > From: Borislav Petkov <bp@xxxxxxx>
> > > 
> > > The "x86, AMD: Enable WC+ memory type on family 10 processors" patch
> > > currently in -tip added a workaround for AMD F10h CPUs which #GPs my
> > > guest when booted in kvm. This is because it accesses MSR_AMD64_BU_CFG2
> > > which is not currently ignored by kvm. Do that because this MSR is only
> > > baremetal-relevant anyway. While at it, move the ignored MSRs at the
> > > beginning of kvm_set_msr_common so that we exit then and there.
> > > 
> > Is your guest compiled without PV support? With PV Linux traps #GP for
> > all MSRs and it saves us in more than one places.
> 
> Yes, CONFIG_PARAVIRT_GUEST is not set on the guest kernel.
> 
Thanks. It does not mean that the patch should not be applied though.
I cannot seems to find the documentation for the MSR anywhere, do you
have a pointer?

--
			Gleb.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/