On 12 August 2013 20:02, Paul Gortmaker <paul.gortma...@windriver.com> wrote: > > If I recall correctly, I'd showed the patch to Russell at the time (via > IRC, I believe) and he'd told me essentially the same thing as the above > paragraph, which is why I didn't put it in the patch system, and why the > commit log of the yocto patch (http://goo.gl/riEZXY) reads as it does > (i.e. it is unclear what the real swizzle is).
That patch reads like "make the kernel work with old (pre 1.5) QEMU behaviour" (where every IRQ for every PCI card was always IRQ27). I'm committing to making QEMU continue to support that for backward compatibility, as well as to "work like hardware" (our autodetect hack is based on what the kernel writes to PCI_INTERRUPT_LINE), so in that sense it's a stable and well defined[*] thing to write to, but for mainline I imagine the kernel will want to just go for the 'work on real h/w' approach. [*] by which I mean "not written down outside the QEMU source code but I will write it up if you need it" :-) -- PMM
