On Tue, Nov 27, 2018 at 05:50:50PM +0000, Jean-Philippe Brucker wrote: > > I didn't notice this in the past but it seems this will spin > > with interrupts disabled until host handles the request. > > Please do not do this - host execution can be another > > task that needs the same host CPU. This will then disable > > interrupts for a very very long time. > > In the guest yes, but that doesn't prevent the host from running another > task right? My tests run fine when QEMU is bound to a single CPU, even > though vcpu and viommu run in different threads So a kind of a solution is to add a config space field for sync. That at least can give host a hint that yes, vcpu is stopped now and it should do something else. Not ideal but better than polling VQ forever. -- MST
