Re: [PATCH v6 6/7] KVM: arm64: allow get exception information from userspace

From: gengdongjiu
Date: Wed Sep 27 2017 - 11:37:25 EST


>> What you may be seeing is some awkwardness with the change in the SError ESR
>> with v8.2. Previously the VSE mechanism injected an impdef SError, (but they
>> were all impdef so it didn't matter).
>> With VSESR_EL2 KVM has to specify one, and all-zeros is a bad choice as this
>> means 'classified as a RAS error ... unknown!'.
>>
>> I have a patch in the upcoming SError/RAS series that changes KVMs virtual-abort
>> code to specify an impdef ESR for this path.
> Before I remember Marc and you suggest me specify the an impdef ESR (set the vsesr_el2) in
> the userspace,

I pasted Marc's propose and your suggestion that set VSESR_EL2(specify
virtual SError syndrome) by the user space.
https://lkml.org/lkml/2017/3/20/441
https://lkml.org/lkml/2017/3/20/516


> now do you want to specify an impdef ESR in KVM instead of usrspace?
> if setting the vsesr_el2 in the KVM, whether user-space need to specify?
> May be we can combine the patches that specify an impdef ESR(set vsesr_el2) patch to one.
>