Loading the KVM module (Fedora 19 on ppc64, POWER7)

[Andrej Podzimek]

Hello,

I'm trying to run libvirtd and KVM on a POWER7 machine. For some reason, virt-manager
on a client says there is no KVM support. :-( The KVM module installed on the system
cannot be loaded:

	# modprobe kvm
	modprobe: ERROR: could not insert 'kvm': Input/output error

There are no new messages in dmesg. Presumably, the file
/lib/modules/3.10.11-200.fc19.ppc64p7/kernel/arch/powerpc/kvm/kvm.ko is readable; at least
sha1sum can read it. This is how the error appears in strace (from open()ing the module to
an unsuccessful kcmp()):

	open("/lib/modules/3.10.11-200.fc19.ppc64p7/kernel/arch/powerpc/kvm/kvm.ko",
O_RDONLY|O_CLOEXEC) = 3
	read(3, "\177ELF\2\2", 6)               = 6
	lseek(3, 0, SEEK_SET)                   = 0
	fstat(3, {st_mode=S_IFREG|0744, st_size=273976, ...}) = 0
	mmap(NULL, 273976, PROT_READ, MAP_PRIVATE, 3, 0) = 0x1fffffad0000
	kcmp(0x3, 0x1ffffff68330, 0, 0x3, 0)    = -1 EIO (Input/output error)

The OS is a fresh Fedora 19 installation with kernel.ppc64p7 3.10.11-200.fc19.

Perhaps this could be a known issue or a glitch related to SELinux, but I have no idea
what to try next. Could someone give me a hint, please?

Cheers!
Andrej

[Richard W.M. Jones]

On Mon, Sep 23, 2013 at 11:07:41AM +0200, Andrej Podzimek wrote:
>  Hello,
>  
>  I'm trying to run libvirtd and KVM on a POWER7 machine. For some reason, virt-manager
> on a client says there is no KVM support. :-( The KVM module installed on the system
> cannot be loaded:
>  
>  	# modprobe kvm
>  	modprobe: ERROR: could not insert 'kvm': Input/output error 
Does your POWER7 machine actually support hardware virtualization?
Unfortunately our latest kernels have disabled Alex's PR KVM because
it wasn't compatible with HV KVM.  I've seen some patches floating
around (not upstream AFAIK) to fix it so both can be configured
together.

>  	kcmp(0x3, 0x1ffffff68330, 0, 0x3, 0)    = -1 EIO (Input/output
> error) 
This could be a whole range of problems.  Probably best to dive into
the kernel code and find out what the real error is  :-(

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-df lists disk usage of guests without needing to install any
software inside the virtual machine.  Supports Linux and Windows.
http://people.redhat.com/~rjones/virt-df/