Linux x86 guest panics in skb_copy_bits

Justin Dossey
2009-05-03T18:40:47Z

Hi all,

I have a pretty straightforward setup.

Hypervisor:
dual xeon e5205 running Gentoo Linux
kernel 2.6.27 with virtio devices enabled
kvm 84
libvirt 0.5.1

Guest:
32-bit, virtio for nic and disk, qcow2.
Linux 2.6.28.

Network is bridged using tap and brctl.

I'm running Apache on the guest.  Whenever I send enough data through
the virtual NIC, I get a panic in skb_copy_bits.  I've tried using the
e1000 driver instead of the virtio one, but that makes no difference.

Has anyone else seen this behavior before?  I got this on 2.6.27 and 2.6.28.

Here's a snippet:

[280204.340016]  [<c02253e2>] panic+0x4e/0xea
[280204.340016]  [<c05906b9>] oops_end+0x8f/0xa3
[280204.340016]  [<c0204e94>] die+0x57/0x5f
[280204.340016]  [<c0592192>] do_page_fault+0x605/0x6bc
[280204.340016]  [<c059010d>] ? _spin_lock+0x15/0x18
[280204.340016]  [<c04bfad8>] ? __qdisc_run+0xe6/0x1a7
[280204.340016]  [<c0591b8d>] ? do_page_fault+0x0/0x6bc
[280204.340016]  [<c0590482>] error_code+0x72/0x78
[280204.340016]  [<c04ace8c>] ? skb_copy_bits+0x4f/0x1c4
[280204.340016]  [<c0215864>] ? kvm_set_pte+0x26/0x29
[280204.340016]  [<c054889c>] xdr_skb_read_bits+0x1f/0x37
[280204.340016]  [<c054872b>] xdr_partial_copy_from_skb+
0x117/0x16c