Error : virHostCPUGetKVMMaxVCPUs:1228 : KVM is not supported on this platform: Function not implemented.

[Daniel P. Berrangé]

On Tue, Aug 29, 2023 at 09:22:35PM +0200, Mario Marietto wrote:
> Hello.
> 
> I'm running Debian bookworm on my ARM Chromebook,model "xe303c12" and
> I've recompiled the kernel (5.4) to enable KVM,so now my system sounds like
> this :

That's surely not the default kernel that comes with Debian bookworm,
as that 5.4 version is many years old.

IIUC the standard bookworm kernel will be 6.4

> root at chromarietto:~#  virsh domcapabilities --machine virt
> --emulatorbin /usr/local/bin/qemu-system-arm
> 
> 2023-08-29 10:17:59.110+0000: 1763: error : virHostCPUGetKVMMaxVCPUs:1228 :
> KVM is not supported on this platform: Function not implemented ;
> error: failed to get emulator capabilities
> error: KVM is not supported on this platform: Function not implemented

This shows libvirt was built against a kernel that lacks the
kvm.h header file.

This is expected for armv7 as support for KVM on 32-bit arm was
deleted in the 5.7 kernel. I expect libvirt was built against
the kernel headers from Debian's default 6.4 kernel and thus
lacks KVM support.

Your booting of the old 5.4 kernel doesn't solve this - you
would actually need to build libvirt (and QEMU) against this
outdated kernel too.


With regards,
Daniel
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