Re: [PATCH] kvm: don't clear level from irqfd

Gleb Natapov
2012-06-27T10:03:49Z

On Wed, Jun 27, 2012 at 12:13:43PM +0300, Michael S. Tsirkin wrote:
> irqfd sets and clears the level immediately.
> This used to be necessary for MSI interrupts but isn't anymore.
>
> Note! We never officially supported irqfd for level
> interrupts but it usually seemed to kind of work,
> and this change will break it. There are no known
> real users of that feature though - only old vfio prototypes.
> Removing this line will make it easier to add
> real support for level irqfds in the future.
>
Did we officially supported irqfd for ioapic/pic edge interrupts?
Because those will break to.

> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
> virt/kvm/eventfd.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
> index f59c1e8..4db6b01 100644
> --- a/virt/kvm/eventfd.c
> +++ b/virt/kvm/eventfd.c
> @@ -68,7 +68,6 @@ irqfd_inject(struct work_struct *work)
> struct kvm *kvm = irqfd->kvm;
>
> kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID, irqfd->gsi, 1);
> - kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID, irqfd->gsi, 0);
> }
>
> /*
> --
> MST

--
Gleb.