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Re: [Xen-devel] Xen HVM regression on certain Intel CPUs

On 03/27/2013 09:24 AM, Stefan Bader wrote:
>> When you say Xen HVM, am I correct in assuming that neither CPUID
>> nor CR4 operations in the main kernel are run through
>> paravirt_ops?
> Not paravirt ops likely but the hypervisor traps access. At least
> cpuid from within a hvm guest I expect to be filtered. So when
> checking things I went to bare-metal.
> Will fetch more info and get back.

Hypervisor traps is one thing... they should be consistent no matter
where in the code they happen... unless they are broken.

Try this CPUID program.  This uses the kernel /dev interface which may
be somewhat suboptimal in case CPUID in userspace actually differs,
but it would be interesting to know what it outputs.


Attachment: cpuid.c
Description: Text Data

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