Re: [PATCH] kvm: pass the virtual SEI syndrome to guest OS

[James Morse]

Hi Christoffer,

On 21/03/17 11:34, Christoffer Dall wrote:
> On Tue, Mar 21, 2017 at 02:32:29PM +0800, gengdongjiu wrote:
>> On 2017/3/20 23:08, James Morse wrote:
>>>>>> On 20/03/17 07:55, Dongjiu Geng wrote:
>>>>>>> In the RAS implementation, hardware pass the virtual SEI
>>>>>>> syndrome information through the VSESR_EL2, so set the virtual
>>>>>>> SEI syndrome using physical SEI syndrome el2_elr to pass to
>>>>>>> the guest OS
>>>
>>> How does this work with firmware first?
>>
>> I explained it in previous mail about the work flow.
> 
> When delivering and reporting SEIs to the VM, should this happen
> directly to the OS running in the VM, or to the guest firmware (e.g.
> UEFI) running in the VM as well?

'firmware first' is the ACPI specs name for x86's BIOS or management-mode
handling the error. On arm64 we have multiple things called firmware, so the
name might be more confusing than helpful.

As far as I understand it, firmware here refers to the secure-world and EL3.
Something like ATF can use SCR_EL3.EA to claim SErrors and external aborts,
routing them to EL3 where secure platform specific firmware generates CPER records.
For a guest, Qemu takes the role of this EL3-firmware.



Thanks,

James