Re: [PATCH] arm64: KVM: VHE: save and restore some PSTATE bits

[gengdongjiu]

On 2017/9/6 20:00, Vladimir Murzin wrote:
> On 06/09/17 11:35, gengdongjiu wrote:
>> Vladimir,
>>
>> On 2017/9/6 17:41, Vladimir Murzin wrote:
>>> Can you please elaborate on cases where PAN is not enabled?
>>
>> I mean the informal private usage, For example, he disabled the PAN dynamically to let kernel space to access the user space.
>> After he dynamic disabled the PAN, then switched to guest OS. after return to host. he found the PAN stage is modified.
>> Of cause this is not a formal usage, in our host kernel, it is always enabled, no dynamic change, but I means it may exist such cases.
>>
>>
> 
> So, in short, there is no real issue with PAN, right? What about UAO?
For the PAN, if host OS dynamically enable/disable PAN should have issue.
Do you think that is not a issue as above description?

"host OS dynamically disable the PAN, but after go back from the guest OS, The PAN is unexpectedly enabled"

> 
> Cheers
> Vladimir
> 
> .
>