James,

On 2017/9/8 0:31, James Morse wrote:

KVM already handles external aborts from lower exception levels, no more work
needs doing for TEA.

If it is firmware first solution, that is SCR_EL3.EA=1, all SError interrupt and synchronous External
Abort exceptions are taken to EL3, so EL3 firmware will handle it, KVM no needs to handle it.

HCR_EL3.TEA is only for EL3 to check its value to decide to jump to hypervisor or kernel.

What happens when a guest access the RAS-Error-Record registers?

Before we can set HCR_EL2.TERR I think we need to add some minimal emulation for
the registers it traps. Most of them should be RAZ/WI, so it should be
straightforward. (I think KVMs default is to emulate an undef for unknown traps).

Today I added the support to do some minimal emulation for RAS-Error-Record registers, thanks
for the good suggestion.

Eventually we will want to back this with a page of memory that lets
Qemu/kvmtool configure what the guest can see. (i.e. the emulated machine's
errors for kernel-first handling.)