Re: [Qemu-devel] [PATCH 4/4] spapr: Add support for time base offset migration

[Alexander Graf]

On 12.04.14 23:44, Benjamin Herrenschmidt wrote:
> On Sat, 2014-04-12 at 16:31 +0200, Alexander Graf wrote:
> > Don't we generate PHBs on the fly? How exactly is this going to help
> > with the problem at hand?
> We can still assign the interrupts as a fixed function of the PHB
> number...

Yes, but we create those depending on the order with which -device gets 
called IIUC. That's really what the underlying issue is. If we had 500 
prepopulated PHBs that PCI devices get assigned to we wouldn't have the 
problem (but different ones thanks to massive waste of memory and other 
resources).

So we either have to create some way to make interrupt numbering a 
function of something very simple we plug the PHB into, like a virtual 
pseries slot number which we multiply by x to get an irq number range. 
Or we'd have to manually link up PHB IRQ lines to XICS IRQ lines on the 
command line.


Alex