Re: [Qemu-devel] [PATCH 6/6] virtio-pci: use ioeventfd even when KVM is disabled

[Fam Zheng]

On Wed, 06/28 19:47, Stefan Hajnoczi wrote:
> Old kvm.ko versions only supported a tiny number of ioeventfds so
> virtio-pci avoids ioeventfds when kvm_has_many_ioeventfds() returns 0.
> 
> Do not check kvm_has_many_ioeventfds() when KVM is disabled since it
> always returns 0.  Since commit 8c56c1a592b5092d91da8d8943c17777d6462a6f
> ("memory: emulate ioeventfd") it has been possible to use ioeventfds in
> qtest or TCG mode.
> 
> This patch makes -device virtio-blk-pci,iothread=iothread0 work even
> when KVM is disabled.
> 
> I have tested that virtio-blk-pci works under TCG both with and without
> iothread.
> 
> This patch fixes qemu-iotests 068, which was accidentally merged early
> despite the dependency on ioeventfd.
> 
> Cc: Michael S. Tsirkin <address@hidden>
> Signed-off-by: Stefan Hajnoczi <address@hidden>
> Reviewed-by: Michael S. Tsirkin <address@hidden>
> Message-id: address@hidden
> Signed-off-by: Stefan Hajnoczi <address@hidden>

Reviewed-by: Fam Zheng <address@hidden>