Re: [Qemu-devel] [PATCH] kvm-all.c: Move init of irqchip_inject_ioctl out of kvm_irqchip_create()

[Peter Maydell]

On 14 August 2012 08:42, Jan Kiszka <address@hidden> wrote:
> On 2012-08-14 09:40, Peter Maydell wrote:
>> On 14 August 2012 08:33, Jan Kiszka <address@hidden> wrote:
>>> KVM_IRQ_LINE is old-style, deprecated, KVM_IRQ_LINE_STATUS (i.e
>>> injection with feedback to allow lost-tick compensation) is the current
>>> standard that other archs should pick up.
>>
>> Can it be documented in the kernel api.txt then, please? Nobody
>> is going to use it otherwise... (If I'd been paying attention at the
>> time I'd have nak'd the qemu patches that added it on the grounds
>> they were using an undocumented kernel API :-))
>
> The kernel API's documentation has in fact a much younger history than
> KVM support in QEMU. I think we still need to add quite a few standard
> IOCTLs to make it complete. Patches always welcome.

Well, you appear to know what this variant ioctl does and why it's
better than KVM_IRQ_LINE, whereas I don't. I just want to deliver
an interrupt, KVM_IRQ_LINE lets me deliver an interrupt, why
do I need anything more? (What would I do with the status return, for
instance? I have to assert the incoming irq line, there's nothing for
me to do if the kernel says "sorry, can't do that" except abort qemu.)

-- PMM