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

On 06/09/17 13:14, gengdongjiu wrote:

On 2017/9/6 20:00, Vladimir Murzin wrote:

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On 06/09/17 11:35, gengdongjiu wrote:

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Vladimir,

On 2017/9/6 17:41, Vladimir Murzin wrote:

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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"

Do you see effect of "PAN is unexpectedly enabled"?

Cheers
Vladimir

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Cheers
Vladimir

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