Re: [Qemu-devel] [PATCH v7 5/6] Initial implementation of vGICv3

[Peter Maydell]

On 31 July 2015 at 12:12, Pavel Fedin <address@hidden> wrote:
>  Hello!
>
>> >>  I intentionally put some tracing to these conditions. On my
>> >> system KVM_DEV_ARM_VGIC_GRP_NR_IRQS is supported and
>> >> KVM_DEV_ARM_VGIC_CTRL_INIT is not. So will it always be this way?
>> >
>> > That is weird. I thought that the kernel devs had agreed that all
>> > new VGIC code should require explicit initialization (ie that
>> > lazy init-on-first-time-it's-needed was only there for legacy
>> > guests and the old GICv2). The lazy-init stuff was a big source
>> > of bugs where things weren't inited at the point where you
>> > expected, which is why it should have gone away...
>>
>> I just checked with Marc, and he agreed that all kernels
>> with GICv3 support should support VGIC_CTRL_INIT. What kernel
>> are you running?
>
>  v3.18 with backported GICv3 support. It is a choice of our
> HW vendor and their current official kernel.

Sounds like their backporting is buggy, then. They need to
fix it, I don't think we need to support broken branches
in QEMU.

thanks
-- PMM