[ros-dev] [ros-diffs] [jgardou] 50991: [NTOSKRNL] - Print supported CPU features. - Simplify detection of non working but claimed SYSENTER support for intel processors - Workaround a virtualbox "feature" : claim that SY...

[Aleksey Bragin]

On Mar 7, 2011, at 4:33 PM, jgardou at svn.reactos.org wrote:

> Author: jgardou
>              /* Check if the CPU is too old to support SYSENTER */
> -            if ((Prcb->CpuType < 6) ||
> -                ((Prcb->CpuType == 6) && (Prcb->CpuStep < 0x0303)))
> +            if ((Reg[0] & 0x0FFF3FFF) < 0x00000633)
>              {
It was intentionally done over CpuType and CpuStep. Now you  
criptified it back to a raw Reg[0] value and weird hardcoded  
constant. Could you please 1) elaborate this change and 2) if you  
still think it's correct, and if you still tihnk(!) Windows does it  
same way, then rework it to use Prcb->Cpu* instead of these magic  
values?

Not to say adding a hack for VirtualBox is far from being a  
beautiful, and would need to be *at least* marked so that it's not  
forgotten.

Thanks,
Aleksey Bragin.