Re: [Qemu-devel] [PATCH v3 00/20] GICv3 emulation

[Laszlo Ersek <lersek@redhat.com>]

On 06/23/16 16:18, Ed Maste wrote:
> On 23 June 2016 at 07:36, Laszlo Ersek <lersek@redhat.com> wrote:
>> On 06/22/16 22:53, Peter Maydell wrote:
>>> On 22 June 2016 at 19:09, Ed Maste <emaste@freebsd.org> wrote:
>>>> On 15 June 2016 at 06:10, Peter Maydell <peter.maydell@linaro.org> wrote:
>>>>>
>>>>> A quick scan through http://fxr.watson.org/fxr/source/arm64/arm64/gic_v3.c
>>>>> doesn't seem to show it setting the IGROUPR registers anywhere,
>>>>> so it probably is a guest bug. (You can use "-d 'trace:gicv3*'" to
>>>>> enable the tracepoints for the GIC which would let you check whether
>>>>> the guest ever tries to write to the group config registers.)
>>>>
>>>> Is there a prebuilt QEMU_EFI.fd available somewhere for testing a
>>>> FreeBSD change to address this? I've been using the prebuilt ones from
>>>> https://wiki.linaro.org/LEG/UEFIforQEMU and the latest one I had did
>>>> not start with gic-version=3.
>>>
>>> Yeah, it looks like the same bug is also present in UEFI itself
>>> (it's super popular!). Laszlo, Ard, do you have a prebuilt
>>> UEFI binary with Ard's fix?
>>
>> I just put up one here, in case it's still needed:
>>
>> http://people.redhat.com/~lersek/82a5e88f-f1e1-42e2-8462-66974c9cbfff/
> 
> Thank you. I ran your QEMU_EFI.fd with gic_version=3 and UEFI and
> FreeBSD start up successfully (as expected, based on the discussion in
> this thread).
> 
> It sounds like we'll need to build a hacked UEFI build as Peter
> Maydell suggested in order to actually test a FreeBSD fix when we have
> it.

Ah, sorry, I failed to understand this nuance from the discussion
(although I quoted it myself -- sorry I'm not having a great day today).
So apparently you need a recent enough firmware binary that *starts*
with gicv3, but doesn't configure the gicv3 as otherwise needed, so you
can reproduce the FreeBSD bug, and verify the FreeBSD bugfix, while
booting with UEFI.

Ard's patch has just been committed to upstream edk2 (c7fefb690661 --
<https://github.com/tianocore/edk2/commits/master>), but I can build a
binary for you right before it (at
bf57a42a0e2cf1c68e9db2f61c82ce93c806ab07)...

http://people.redhat.com/~lersek/82a5e88f-f1e1-42e2-8462-66974c9cbfff/QEMU_EFI.fd.bf57a42a0e2c

Thanks
Laszlo