Comment 39 for bug 1003624

Similar bug...
System crashes randomly - on reboot, on login...
Ubuntu Server 12.04 64 bit + xen hypervisor 4.1, fresh install, only dom0 running.
System crashes randomly - on reboot, on login, sometimes even with kernel panic.

[74385.616601] ------------[ cut here ]------------
[74385.616699] WARNING: at /build/buildd/linux-3.2.0/mm/slub.c:3371 ksize+0xb5/0xc0()
[74385.616828] Hardware name:
[74385.616885] Modules linked in: xen_gntdev xen_netback xen_blkback xen_evtchn xenfs bridge stp radeon ttm drm_kms_helper drm i2c_algo_bit ipmi_si ipm
i_msghandler mac_hid i3000_edac edac_core lp parport raid10 raid456 async_pq async_xor xor async_memcpy async_raid6_recov e1000 e1000e sata_sil24 flopp
y raid6_pq async_tx raid1 raid0 multipath linear
[74385.617996] Pid: 3375, comm: env Tainted: G D W 3.2.0-23-generic #36-Ubuntu
[74385.618127] Call Trace:
[74385.618180] [<ffffffff8106712f>] warn_slowpath_common+0x7f/0xc0
[74385.618285] [<ffffffff8106718a>] warn_slowpath_null+0x1a/0x20
[74385.618384] [<ffffffff81161b55>] ksize+0xb5/0xc0
[74385.618470] [<ffffffff8113287c>] kzfree+0x1c/0x40
[74385.618560] [<ffffffff812d65fa>] apparmor_file_free_security+0x1a/0x20
[74385.618672] [<ffffffff8129d6e6>] security_file_free+0x16/0x20
[74385.618771] [<ffffffff81179006>] __fput+0xc6/0x210
[74385.618863] [<ffffffff81179175>] fput+0x25/0x30
[74385.618945] [<ffffffff81141905>] remove_vma+0x45/0x90
[74385.619032] [<ffffffff81142ba3>] do_munmap+0x1f3/0x2f0
[74385.619122] [<ffffffff81144333>] sys_munmap+0x53/0x80
[74385.619210] [<ffffffff81664a82>] system_call_fastpath+0x16/0x1b
[74385.619311] ---[ end trace 3e4ce9875a6d43f0 ]---
[74385.619403] ------------[ cut here ]------------
[74385.619483] kernel BUG at /build/buildd/linux-3.2.0/mm/slub.c:3427!
[74385.619594] invalid opcode: 0000 [#2] SMP
[74385.619683] CPU 1
[74385.619726] Modules linked in: xen_gntdev xen_netback xen_blkback xen_evtchn xenfs bridge stp radeon ttm drm_kms_helper drm i2c_algo_bit ipmi_si ipmi_msghandler mac_hid i3000_edac edac_core lp parport raid10 raid456 async_pq async_xor xor async_memcpy async_raid6_recov e1000 e1000e sata_sil24 floppy raid6_pq async_tx raid1 raid0 multipath linear
[74385.620062]
[74385.620062] Pid: 3375, comm: env Tainted: G D W 3.2.0-23-generic #36-Ubuntu /S3000AH
[74385.620062] RIP: e030:[<ffffffff811620f5>] [<ffffffff811620f5>] kfree+0x135/0x140
[74385.620062] RSP: e02b:ffff8801dc1cfe08 EFLAGS: 00010246
[74385.620062] RAX: 0200000000000000 RBX: ffff880100000000 RCX: 0000000000000000
[74385.620062] RDX: ffffffff7fffffff RSI: 0000000000000000 RDI: ffff880100000000
[74385.620062] RBP: ffff8801dc1cfe38 R08: ffffea0004000000 R09: 0000000000000000
[74385.620062] R10: ffff880100000000 R11: 0000000000001000 R12: 0000000000000010
[74385.620062] R13: ffff8801dd21a180 R14: ffffffff81132891 R15: ffff8801e4ccd550
[74385.620062] FS: 00007fa643074700(0000) GS:ffff8801f1cb9000(0000) knlGS:0000000000000000
[74385.620062] CS: e033 DS: 0000 ES: 0000 CR0: 000000008005003b
[74385.656105] CR2: 0000000000401008 CR3: 00000001db98f000 CR4: 0000000000002660
[74385.656105] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[74385.656105] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[74385.656105] Process env (pid: 3375, threadinfo ffff8801dc1ce000, task ffff8801df50dbc0)
[74385.656105] Stack:
[74385.656105] ffff8801dc1cfe18 ffff880100000000 0000000000000010 ffff8801dd21a180
[74385.656105] ffff8801e4ccd550 ffff8801e4ccd550 ffff8801dc1cfe58 ffffffff81132891
[74385.656105] 000000000000001d ffff8801dbca0e00 ffff8801dc1cfe68 ffffffff812d65fa
[74385.656105] Call Trace:
[74385.656105] [<ffffffff81132891>] kzfree+0x31/0x40
[74385.656105] [<ffffffff812d65fa>] apparmor_file_free_security+0x1a/0x20
[74385.656105] [<ffffffff8129d6e6>] security_file_free+0x16/0x20
[74385.656105] [<ffffffff81179006>] __fput+0xc6/0x210
[74385.656105] [<ffffffff81179175>] fput+0x25/0x30
[74385.656105] [<ffffffff81141905>] remove_vma+0x45/0x90
[74385.656105] [<ffffffff81142ba3>] do_munmap+0x1f3/0x2f0
[74385.656105] [<ffffffff81144333>] sys_munmap+0x53/0x80
[74385.656105] [<ffffffff81664a82>] system_call_fastpath+0x16/0x1b
[74385.656105] Code: 89 da 4c 89 c6 e8 7e 66 4e 00 eb 94 49 f7 00 00 c0 00 00 74 16 4c 89 c7 e8 09 1a fc ff e9 7e ff ff ff 4d 8b 40 30 e9 27 ff ff ff <0f> 0b 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 53 48 83 ec 08 66
[74385.656105] RIP [<ffffffff811620f5>] kfree+0x135/0x140
[74385.656105] RSP <ffff8801dc1cfe08>
[74385.656105] ---[ end trace 3e4ce9875a6d43f1 ]---