On 30 May 2018 at 17:59, Paolo Bonzini <pbonz...@redhat.com> wrote: > On 21/05/2018 17:02, Peter Maydell wrote: >> On 21 May 2018 at 15:34, Paolo Bonzini <pbonz...@redhat.com> wrote: >>> Why do the levels have to be migrated at all? It should be enough if >>> the IRQ level is either migrated manually, or restored (e.g. in >>> post_save callbacks) through other data that is migrated. >> This is standard behaviour for devices: they track their >> inbound irq/gpio lines, and then that becomes internal state for >> them that must be migrated. > > But or_irq's input are another device's outbound lines, so tracking them > should not be necessary. The other device would do it for or_irq.
There's no mechanism in qemu_irq for the destination end to ask the source end about its current value. The information flow is strictly one-way. thanks -- PMM
