On Sat, Jan 31, 2009 at 6:20 PM, Bryan McLellan <btm@xxxxxxxxxxxxxx> wrote: > On Sat, Jan 31, 2009 at 11:55 AM, Glauber Costa <glommer@xxxxxxxxx> wrote: >>> Since this is a pretty standard mechanism, it may make sense to include this >>> signature in /proc/cpuinfo if someone is up to writing a patch. It could >>> also be useful to expose the PV features mask in cpuinfo too. >>> >> >> What for? We already expose a QEMU cpu type that shows up in cpuinfo as so. >> All we'd have to do would be put the kvm information in the cpu type >> too. This would work >> in all kernels, without the need to patch. > > I'm not sure what you mean by "run cpuid function". On my intrepid kvm > guest running 2.6.27 the cpuid utility has no options to specify a > fucntion, nor do the numbers you provided match any in the e[abcd]x > columns it returns. A google search for "run cpuid function" returns > no results. It's not an utility. It's an asm instruction (that could be easily converted into an utility). This is the very instruction that the kernel uses to grab information that end up in /proc/cpuinfo > > It would be nice to have KVM information somewhere to more easily > differentiate between qemu. However briefly perusing the pv_info > struct in the kernel source shows useful information like the > virtualization type (beyond kvm, including xen and others) and > paravirtualization information. > > There should be some method to tell we're on kvm without utilities > that aren't in most distros base install and ideally it should be > simble. Xen exposes /proc/xen from which one can determine these > things. I'm not arguing for that, but I'm saying it works. > I don't disagree. But I believe exposing it in the cpu model makes it easier, since we won't then depend on any kind of kernel patch. It'll work no matter how old your guest is. -- Glauber Costa. "Free as in Freedom" http://glommer.net "The less confident you are, the more serious you have to act." -- 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
