RE: [patch] fix kvm_arch_vcpu_ioctl_[gs]et_regs()

Jes Sorensen wrote:
> Zhang, Xiantao wrote:
>> Jes
>>    Good work!  I ever talked about the issue with Avi and wanted to
>> enable the logic with the following patch, and Avi thought it may
>> lead to security issues, so deferred to now :)  
>> 
>> One comment:  We still need the logic to save and restore the vcpu's
>> stack for vcpu resuming to the guest in the same environment.  Maybe
>> you can allocate one buf to save it in kvm_reg structure. Xiantao 
> 
> Hi Xiantao,
> 
> I am with Avi on this one - we shouldn't be passing in pointers like
> that. Either we can increase the size of kvm_regs as you mention, but
> it will become *huge* since the stack is 64KB, or we introduce a new
> ioctl just to handle the stack.
> 
> Do you think it would be a problem having the second ioctl for this? I
> would prefer breaking it into two to avoid the kernel having to
> allocate a 128KB chunk for kvm_regs.

Fine to me to add the ioctl, and it should make the logic clear. 
Xiantao