Re: Setting nx bit in virtual CPU

[Andre Przywara <andre.przywara@amd.com>]

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Avi Kivity wrote:
> On 04/07/2010 11:38 PM, Richard Simpson wrote:
>> On 07/04/10 13:23, Avi Kivity wrote:
>>> Run as root, please.  And check first that you have a file named
>>> /dev/cpu/0/msr.
>>>      
>> Doh!
>>
>> gordon Code # ./check-nx
>> nx: enabled
>> gordon Code #
>>
>> OK, seems to be enabled just fine.  Any other ideas?  I am beginning to
>> get that horrible feeling that there isn't a real problem and it is just
>> me being dumb!
>>    
> 
> I really hope so, because I am out of ideas... :)
> 
> Can you verify check-nx returns disabled on the guest?
> Does /proc/cpuinfo show nx in the guest?

Can you try to boot the attached multiboot "kernel", which just outputs 
a brief CPUID dump?
$ qemu-kvm -kernel cpuid_mb -vnc :0
(Unfortunately I have no serial console support in there yet, so you 
either have to write the values down or screenshot it).
In the 4th line from the button it should print NX (after SYSCALL).

Regards,
Andre.

-- 
Andre Przywara
AMD-Operating System Research Center (OSRC), Dresden, Germany
Tel: +49 351 448-3567-12

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