2017-10-19 22:58 GMT+08:00 James Morse [off-list ref]:

Prior to v8.2's RAS Extensions, the HCR_EL2.VSE 'virtual SError' feature
generated an SError with an implementation defined ESR_EL1.ISS, because we
had no mechanism to specify the ESR value.

On Juno this generates an all-zero ESR, the most significant bit 'ISV'
is clear indicating the remainder of the ISS field is invalid.

With the RAS Extensions we have a mechanism to specify this value, and the
most significant bit has a new meaning: 'IDS - Implementation Defined
Syndrome'. An all-zero SError ESR now means: 'RAS error: Uncategorized'
instead of 'no valid ISS'.

consider again.

I still consider that it is not better set  "Implementation Defined
Syndrome" here.
I know your meaning that An all-zero SError means Uncategorized

From the beginning,  our starting point is KVM is the architecture

related and Qemu/kvmtool is platform related.
Qemu/kvmtool is the role of host firmware.
so we let Qemu to create APEI/GHES table and record CPER,
and also injects SEA/SEI in the Qemu.

About the vsesr_el2 which is used to specify the guest ESR,   also all
set by Qemu/kvmtool are better.
including the three cases  even the ESR are  all-zero(uncategorized).
1. IMPLEMENTATION DEFINED
2  categorized,
3  uncategorized,

For this case, Qemu just set the ESR, nothing else, not passing
RAS-error to userspace.