Re: KVM: Fix the invlpg instruction emulation on AMD64

[Aurelien Jarno <aurelien-rXXEIb44qovR7s880joybQ@public.gmane.org>]

Aurelien Jarno a écrit :
> Aurelien Jarno a écrit :
>> Avi Kivity a écrit :
>>> But invlpg is defined as having reg == 7! The manual says:
>>>
>>> 0F 01/7 INVLPG m
>>>
>>> where "/7" is the notation for "reg in the mod reg r/m byte:
>>>
>>> " /digit — A digit between 0 and 7 indicates that the ModR/M byte of the
>>> instruction uses
>>> only the r/m (register or memory) operand. The reg field contains the
>>> digit that provides an
>>> extension to the instruction's opcode."
>>>
>>>
>>> So what you're seeing is not the invlpg instruction but something else
>>> in the same group.
>>>
>> I see.
>>
>> Anyway the previous behaviour on AMD was to disable SrcMem on all 0F 01
>> instructions. It's actually what I tried to do in the first version of
>> the patch, ie have the same behaviour as the SrcNone case for the 0F 01
>> instructions.
>>
>> The 0F 01 instruction is then correctly emulated, but another of this
> Oops s/0F 01/invlpg/
>> group is probably not, as the patch clearly fix the problem on AMD.
> 

I confirm the problem. SVM does not virtualize smsw and lmsw that have
to be emulated. And it looks like the decoding or/and emulation of those
instructions is currently broken in KVM.

-- 
  .''`.  Aurelien Jarno	            | GPG: 1024D/F1BCDB73
 : :' :  Debian developer           | Electrical Engineer
 `. `'   aurel32-8fiUuRrzOP0dnm+yROfE0A@public.gmane.org         | aurelien-rXXEIb44qovR7s880joybQ@public.gmane.org
   `-    people.debian.org/~aurel32 | www.aurel32.net

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >> http://get.splunk.com/