Re: [Xen-devel] [PATCH] x86/amd: fix crash as Xen Dom0 on AMD Trinitysystems

From: H. Peter Anvin
Date: Wed May 30 2012 - 10:50:28 EST


On 05/30/2012 07:39 AM, Konrad Rzeszutek Wilk wrote:
> On Wed, May 30, 2012 at 03:10:02PM +0200, Andre Przywara wrote:
>> Because we are behind a family check before tweaking the topology
>> bit, we can use the standard rd/wrmsr variants for the CPUID feature
>> register.
>> This fixes a crash when using the kernel as a Xen Dom0 on affected
>> Trinity systems. The wrmsrl_amd_safe is not properly paravirtualized
>> yet (this will be fixed in another patch).
>
> So with a rdmsrl_amd_safe and wrmsrl_amd_safe being implemented in
> the pv_cpu_ops - would this patch even be neccessary?
>

That is still bogus; a better thing would be to implement the _regs
interface. Even better would be to trap and emulate rdmsr/wrmsr!

-hpa

--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

--
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/