On 20/11/2019 05:17, David Gibson wrote: > On Thu, Oct 17, 2019 at 03:42:06PM +0200, Cédric Le Goater wrote: >> On 17/10/2019 10:43, Cédric Le Goater wrote: >>> On 17/10/2019 07:42, David Gibson wrote: >>>> Traditional PCI INTx for vfio devices can only perform well if using >>>> an in-kernel irqchip. Therefore, vfio_intx_update() issues a warning >>>> if an in kernel irqchip is not available. >>>> >>>> We usually do have an in-kernel irqchip available for pseries machines >>>> on POWER hosts. However, because the platform allows feature >>>> negotiation of what interrupt controller model to use, we don't >>>> currently initialize it until machine reset. vfio_intx_update() is >>>> called (first) from vfio_realize() before that, so it can issue a >>>> spurious warning, even if we will have an in kernel irqchip by the >>>> time we need it. >>>> >>>> To workaround this, make a call to spapr_irq_update_active_intc() from >>>> spapr_irq_init() which is called at machine realize time, before the >>>> vfio realize. This call will be pretty much obsoleted by the later >>>> call at reset time, but it serves to suppress the spurious warning >>>> from VFIO. >>>> >>>> Cc: Alex Williamson <alex.william...@redhat.com> >>>> Cc: Alexey Kardashevskiy <a...@ozlabs.ru> >>>> >>>> Signed-off-by: David Gibson <da...@gibson.dropbear.id.au> >>>> --- >>>> hw/ppc/spapr_irq.c | 11 ++++++++++- >>>> 1 file changed, 10 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/hw/ppc/spapr_irq.c b/hw/ppc/spapr_irq.c >>>> index 45544b8976..bb91c61fa0 100644 >>>> --- a/hw/ppc/spapr_irq.c >>>> +++ b/hw/ppc/spapr_irq.c >>>> @@ -345,6 +345,14 @@ void spapr_irq_init(SpaprMachineState *spapr, Error >>>> **errp) >>>> >>>> spapr->qirqs = qemu_allocate_irqs(spapr_set_irq, spapr, >>>> smc->nr_xirqs + SPAPR_XIRQ_BASE); >>>> + >>>> + /* >>>> + * Mostly we don't actually need this until reset, except that not >>>> + * having this set up can cause VFIO devices to issue a >>>> + * false-positive warning during realize(), because they don't yet >>>> + * have an in-kernel irq chip. >>>> + */ >>>> + spapr_irq_update_active_intc(spapr); >>> >>> This will call the de/activate hooks of the irq chip very early >>> before reset and CAS, and won't call them at reset if the intc >>> pointers are the same (xive only for instance). It breaks very >>> obviously the emulated XIVE device which won't reset the OS CAM >>> line with the CPU id values and CPU notification will be broken. >>> >>> We have to find something else. >> >> Here is a possible fix for the (re)setting of the OS CAM line. >> >> Removing spapr_xive_set_tctx_os_cam() is a good thing but this solution >> shows some issues in our modeling of hot-plugged CPUS with a reset() >> being called at realize(). > > Ok, I've applied the patch below now.
Yes. this was replaced by : http://patchwork.ozlabs.org/cover/1181522/ > Does that mean that my 5/5 patch should be good now? We should. C.
