Re: [Qemu-devel] [PATCH 2/3] target/arm/kvm: split pmu init from creation

[Andrew Jones]

On Mon, Jul 10, 2017 at 04:27:35PM +0100, Peter Maydell wrote:
> On 1 July 2017 at 17:47, Andrew Jones <address@hidden> wrote:
> > When adding a PMU with a userspace irqchip we only do the INIT
> > stage of the device creation.
> 
> Can you explain why? My assumption would be that either
> (a) we don't need the kernel's PMU, in which case don't
> create it at all, or
> (b) we do need the kernel's PMU, so we should both create
> and INIT it.
> 
> If we do one but not the other then we've left a half
> created and unusable PMU device in the kernel, haven't we?
>

I should have renamed the 'create' function to 'set_irq', then
it would make sense, because after the split done by this patch
'create' only sets the irq, which can only be done with an
in-kernel irqchip. Both irqchip types still require INIT though,
see kernel doc Documentation/virtual/kvm/devices/vcpu.txt.

I'll send a v2 that renames the create function. But, before I do,
assuming the rename, do you have another comments on this or the
next patch? We might as well batch all the changes :-)

Thanks,
drew