rdmsr from userspace

[Andriy Gapon]

on 17/05/2008 18:37 Rui Paulo said the following:
> Andriy Gapon wrote:
>>
>> It seems that rdmsr instruction can be executed only at the highest 
>> privilege level and thus is not permitted from userland. Maybe we 
>> should provide something like Linux /dev/cpu/msr?
>> I don't like interface of that device, I think that ioctl approach 
>> would be preferable in this case.
>> Something like create /dev/cpuN and allow some ioctls on it: 
>> ioctl(cpu_fd, CPU_RDMSR, arg).
>> What do you think?
>>
> 
> While I think this (devcpu) is good for testing and development, I 
> prefer having a device driver to handle that specific MSR than a generic 
> /dev/cpuN where you can issue MSRs.
> Both for security and reliability reasons.

What about /dev/pci, /dev/io? Aren't they a precedent?


-- 
Andriy Gapon