[libvirt] [Question] vhost-user hotplug: multiqueue hotplug seems doesn't pass mq and vectors

Gaohaifeng (A) gaohaifeng.gao at huawei.com
Thu Dec 1 06:03:54 UTC 2016


OK. I will try to provide a patch. 

On 30.11.2016 10:02, Gaohaifeng (A) wrote:
> I think we should pass it. Two reasons:
> 1. in none hotplug, we will pass it. We can see from libvirt function 
> qemuBuildVhostuserCommandLine, it will pass queue num as vhostfdSize 
> 2. If we don't pass vectors, qemu will use default value. Now default 
> value is 3, (qemu codes: DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, 3)) So that qemu init msix table with 3 vectors(qemu function: msix_init_exclusive_bar), this will cause Guest can only use 3 interrupts at most. Actually, it use Two, one for config one for other virtqueues.

I see. Do you want to provide a patch or should I do that?

Michal




More information about the libvir-list mailing list