Re: Re: APIC rework

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

> At least dom0 parses this info from DSDT, so we can't have the assuption whether it is used or not, I think. And I also agree to add a new physdev_op to handle this case, and it should be better way to go.  
> Based on this idea, I worked out the patch, attached!  In this patch, we introduced a new physdev_op PHYSDEVOP_setup_gsi for each GSI setup, and each domain can require to map each GSI in this case. 
> In addition, I believe it is very safe to port the hypervisor patch to xen-3.4-x tree and keeps pv_ops dom0 running on it, since no logic is changed.  BTW, I also tested apic and non-apic cases, they works fine after applying the patches. 

But I don't think you tested PCI front and PCI back.

Mainly these lines worry me (can you inline the patch next time too, please):

+               map_irq.domid = DOMID_SELF;                                                                                                
+               map_irq.type = MAP_PIRQ_TYPE_GSI;                                                                                          
+               map_irq.index = gsi;                                                                                                       
+               map_irq.pirq = irq;                                                                                                        
+               rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);                                                                  

For PCI passthrough to work, the domid needs to be for the guest domain, while
in this case it is set to Dom0.

There is already a method of extracting the domain id for PCI devices passed to
the guest. Look in the 'xen_create_msi_irq' function.