kernel crash on EC2 raring

I was running an EC2 instance of raring beta2, and playing with lxc. The system locked up, and I saw:

[30147690.704899] ------------[ cut here ]------------
[30147690.704912] Kernel BUG at ffffffff816c6edc [verbose debug info unavailable]
[30147690.704919] invalid opcode: 0000 [#1] SMP
[30147690.704925] Modules linked in: veth(F) ipt_MASQUERADE(F) iptable_nat(F) nf_conntrack_ipv4(F) nf_defrag_ipv4(F) nf_nat_ipv4(F) nf_nat(F) nf_conntrack(F) ip_tables(F) x_tables(F) bridge(F) stp(F) llc(F) isofs(F) dm_crypt(F) ghash_clmulni_intel(F) aesni_intel(F) aes_x86_64(F) xts(F) lrw(F) gf128mul(F) ablk_helper(F) cryptd(F) microcode(F) acpiphp(F)
[30147690.704963] CPU 0
[30147690.704969] Pid: 25624, comm: find Tainted: GF 3.8.0-12-generic #21-Ubuntu
[30147690.704975] RIP: e030:[<ffffffff816c6edc>] [<ffffffff816c6edc>] vmalloc_fault+0x1dc/0x20e
[30147690.704990] RSP: e02b:ffff8800056cba30 EFLAGS: 00010046
[30147690.704995] RAX: ffff88000efeeff8 RBX: ffffe8ffffc00980 RCX: 0000000000000000
[30147690.705000] RDX: 00003ffffffff000 RSI: ffff880000000ff8 RDI: 0000000000000000
[30147690.705007] RBP: ffff8800056cba50 R08: ffff88006590a7e8 R09: 0000000000637000
[30147690.705012] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88000ef23e88
[30147690.705020] R13: ffff88000efeeff8 R14: ffff880000000ff8 R15: 0000000000000000
[30147690.705030] FS: 00007f51502c4740(0000) GS:ffff880069c00000(0000) knlGS:0000000000000000
[30147690.705037] CS: e033 DS: 0000 ES: 0000 CR0: 000000008005003b
[30147690.705042] CR2: ffffe8ffffc00980 CR3: 000000000ef23000 CR4: 0000000000002660
[30147690.705048] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[30147690.705054] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[30147690.705061] Process find (pid: 25624, threadinfo ffff8800056ca000, task ffff880065cfae80)
[30147690.705067] Stack:
[30147690.705070] 0000000000000029 0000000000000002 ffffe8ffffc00980 ffff8800056cbb68
[30147690.705080] ffff8800056cbb48 ffffffff816c720c 0000000000000200 ffff880065cfae80
[30147690.705089] 0000000000000068 ffff8800155d529c ffff8800135e8540 ffff8800056cba98
[30147690.705098] Call Trace:
[30147690.705104] [<ffffffff816c720c>] __do_page_fault+0x1ec/0x4e0
[30147690.705116] [<ffffffff81085c3a>] ? lg_local_unlock+0x1a/0x20
[30147690.705125] [<ffffffff811a888e>] ? prepend_path+0x9e/0x1f0
[30147690.705134] [<ffffffff8114cc89>] ? zone_statistics+0x99/0xc0
[30147690.705141] [<ffffffff8114cc89>] ? zone_statistics+0x99/0xc0
[30147690.705147] [<ffffffff816c750e>] do_page_fault+0xe/0x10
[30147690.705154] [<ffffffff816c3b58>] page_fault+0x28/0x30
[30147690.705162] [<ffffffff81188144>] ? mem_cgroup_charge_statistics.isra.20+0x14/0x50
[30147690.705170] [<ffffffff8118a1f0>] __mem_cgroup_uncharge_common+0xd0/0x2d0
[30147690.705178] [<ffffffff8118d73a>] mem_cgroup_uncharge_page+0x2a/0x30
[30147690.705185] [<ffffffff81162ef9>] page_remove_rmap+0x89/0x160
[30147690.705193] [<ffffffff81156d74>] unmap_page_range+0x4a4/0x750
[30147690.705200] [<ffffffff8100122a>] ? xen_hypercall_xen_version+0xa/0x20
[30147690.705207] [<ffffffff811570aa>] unmap_single_vma+0x8a/0x100
[30147690.705214] [<ffffffff81157909>] unmap_vmas+0x49/0x90
[30147690.705220] [<ffffffff8115fcf8>] exit_mmap+0x98/0x170
[30147690.705229] [<ffffffff810559d4>] mmput+0x64/0x100
[30147690.705236] [<ffffffff8105e302>] do_exit+0x242/0x9d0
[30147690.705243] [<ffffffff8119557e>] ? ____fput+0xe/0x10
[30147690.705249] [<ffffffff8105eb0f>] do_group_exit+0x3f/0xa0
[30147690.705255] [<ffffffff8105eb87>] sys_exit_group+0x17/0x20
[30147690.705263] [<ffffffff816cbb1d>] system_call_fastpath+0x1a/0x1f
[30147690.705268] Code: de 48 89 d7 e8 08 f1 fe ff 48 f7 00 01 01 00 00 49 89 c5 74 3c 4c 89 f7 48 89 de e8 f1 f0 fe ff 48 8b 38 f7 c7 01 01 00 00 75 02 <0f> 0b ff 14 25 a8 35 c2 81 48 89 c2 49 8b 7d 00 ff 14 25 a8 35
[30147690.705329] RIP [<ffffffff816c6edc>] vmalloc_fault+0x1dc/0x20e
[30147690.705336] RSP <ffff8800056cba30>
[30147690.705356] ---[ end trace ba8063f40c0aaa21 ]---
[30147690.705443] Fixing recursive fault but reboot is needed!

full log attached.
---
AlsaDevices:
 total 0
 crw-rw---T 1 root audio 116, 1 Mar 27 14:08 seq
 crw-rw---T 1 root audio 116, 33 Mar 27 14:08 timer
AplayDevices: Error: [Errno 2] No such file or directory
ApportVersion: 2.9.1-0ubuntu1
Architecture: amd64
ArecordDevices: Error: [Errno 2] No such file or directory
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
CRDA: Error: [Errno 2] No such file or directory
CurrentDmesg: [25557234.872217] init: plymouth-stop pre-start process (902) terminated with status 1
DistroRelease: Ubuntu 13.04
Ec2AMI: ami-8c841ae5
Ec2AMIManifest: ubuntu-us-east-1/images-milestone/ubuntu-raring-13.04-beta1-amd64-server-20130313.manifest.xml
Ec2AvailabilityZone: us-east-1c
Ec2InstanceType: m1.small
Ec2Kernel: aki-88aa75e1
Ec2Ramdisk: unavailable
IwConfig:
 eth0 no wireless extensions.

 lo no wireless extensions.
Lspci:

Lsusb: Error: command ['lsusb'] failed with exit code 1: unable to initialize libusb: -99
MarkForUpload: True
Package: linux (not installed)
PciMultimedia:

ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcFB:

ProcKernelCmdLine: root=LABEL=cloudimg-rootfs ro console=hvc0
ProcModules:
 acpiphp 23954 0 - Live 0x0000000000000000 (F)
 dm_crypt 22820 0 - Live 0x0000000000000000 (F)
 isofs 39815 0 - Live 0x0000000000000000 (F)
 microcode 22881 0 - Live 0x0000000000000000 (F)
ProcVersionSignature: User Name 3.8.0-12.21-generic 3.8.2
RelatedPackageVersions:
 linux-restricted-modules-3.8.0-12-generic N/A
 linux-backports-modules-3.8.0-12-generic N/A
 linux-firmware N/A
RfKill: Error: [Errno 2] No such file or directory
Tags: raring ec2-images
Uname: Linux 3.8.0-12-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm audio cdrom dialout dip floppy netdev plugdev video