On Wed, 2015-03-25 at 10:44 +0100, Andrew Jones wrote: > Hello ARM virt maintainers, > > I'd like to start a discussion about supporting virt-what[1]. virt-what > allows userspace to determine if the system it's running on is running > in a guest, and of what type (KVM, Xen, etc.). Despite it being a best > effort tool, see the Caveat emptor in [1], it has become quite a useful > tool, and is showing up in different places, such as OpenStack. If you > look at the code[2], specifically [3], then you'll see how it works on > x86, which is to use the dedicated hypervisor cpuid leaves. I'm > wondering what equivalent we have, or can develop, for arm. > Here are some thoughts; > 0) there's already something we can use, and I just need to be told > about it. > 1) be as similar as possible to x86 by dedicating some currently > undefined sysreg bits. This would take buy-in from lots of parties, > so is not likely the way to go. > 2) create a specific DT node that will get exposed through sysfs, or > somewhere. > 3) same as (2), but just use the nodes currently in mach-virt's DT > as the indication we're a guest. This would just be a heuristic, > i.e. "have virtio mmio" && psci.method == hvc, or something, > and we'd still need a way to know if we're kvm vs. xen vs. ??. FWIW Xen has a specific node, https://git.kernel.org/cgit/linux/kernel/git/devicetree/devicetree-rebasing.git/tree/Bindings/arm/xen.txt Doesn't help you with ACPI systems though. IIRC there will be a Xen table of some sort. Ian. -- 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
