Re: Kernel GPF in vmx_save_host_state()

Avi Kivity
2009-03-18T08:55:39Z

Benjamin Gilbert wrote:
> I accidentally tried to run a 64-bit guest on a 32-bit host. Even
> though this isn't supported, it shouldn't crash my kernel. :-)
>
> CPU: Intel Core 2 Quad
> KVM: kernel kvm-84-640-g967f619, userspace kvm-84-304-g2ced1d8. Also
> occurs with vanilla kvm-84.
> Host kernel: Vanilla 2.6.28
> Host arch: i386
> Guest: Debian Etch x86_64, distributor 2.6.18 kernel
> Commandline: qemu-system-x86_64 -hda debian-etch-x86_64 -m 512
> Occurs with: -no-kvm-irqchip, -no-kvm-pit
> Does not occur with: -no-kvm
>
> As soon as the guest kernel starts, the host produces:
>
> general protection fault: 0000 [#1] PREEMPT SMP
> last sysfs file: /sys/kernel/uevent_seqnum
> Dumping ftrace buffer:
> (ftrace buffer empty)
> Modules linked in: kvm_intel kvm
>
>
> Pid: 6570, comm: qemu-system-x86 Not tainted (2.6.28-686 #4) Precision
> WorkStat
> EIP: 0060:[<f8cf3d97>] EFLAGS: 00010246 CPU: 2
> EIP is at vmx_save_host_state+0x193/0x1a6 [kvm_intel]
> EAX: 00000100 EBX: 00000000 ECX: c0000080 EDX: 00000000
>

From ECX, it looks like it's trying to access EFER and enable LM.

Please provide your /proc/cpuinfo.

> Code: ec 81 e1 01 08 00 00 31 db 89 f2 09 ca 89 55 e0 89 f8 09 d8 89
> 45 e4 be 8

And this line, in full.

--
error compiling committee.c: too many arguments to function