On 29/06/15 15:11, Andre Przywara wrote: > Hi, > > On 29/06/15 13:52, Christoffer Dall wrote: >> Hi Pavel, >> >> [Please cc the kvm/arm list for such patches according to the >> MAINTAINERS file in the future] >> >> On Mon, Jun 29, 2015 at 12:53:46PM +0300, Pavel Fedin wrote: >>> Some hardware (like Raspberry Pi 2) is capable of running KVM, however lacks >>> functional vGIC registers. This series introduces software vGIC emulation for >>> such machines, allowing to fully use virtualization capabilities >> >> Is this rather esoteric use case really worth the extra code in the >> kernel? > > I wonder if these patches would pave the way to support running GICv2 > guests on GICv3s without compat support? Admittedly not a really > compelling use case either, but at least worth discussing, I think. Let's face it: arm64 has no legacy to support. So if you're on a pure GICv3 system, you run a GICv3 guest (oddly enough, pure GICv3 systems are also pure AArch64 systems - see a pattern?). We've made sure the software was available in a timely manner. > Also if this will make the hack needed to enable KVM on RPi2 smaller, > I'd rather embrace this one than letting any random hacks appear on that > RPi kernel tree (patches which I have seen already on some other repo). > If I get this correctly, there are some efforts currently to get closer > to mainline with the RPi tree. Whatever the RPi people do in their tree is their problem. I don't care. I'm interested in supporting *compliant hardware*, and not doing a quick hack on the side. Even if RPi-2 was fully supported in mainline, this code would actively prevent us from supporting proper timer deactivation, for example. > Pavel, is this "broken" GIC you are talking about going to appear in a > publicly available SoC? If yes, you could either state this right now or > send it later once you can talk publicly. > > Marc, Christoffer: > So is this GICv2 CPU interface emulation totally out of question for us > or is it worth at least commenting on the patches? As long as this code is there to support a platform that doesn't exist in a mainline tree, I'm not interested. We have much bigger fish to fry, and supporting what is effectively a broken platform is not exactly high on the agenda. Thanks, M. -- Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
