[Unionfs] kernel oops with unionfs and firefox

[Zhaohui Wang]

Hi all

I got this Oops with unionfs and firefox,any one met this before?

Jun 24 13:58:20 TN5 kernel: [ 3726.857507] Unable to handle kernel NULL pointer dereference at 0000000000000028 RIP: 
Jun 24 13:58:20 TN5 kernel: [ 3726.857514]  [<ffffffff81119c66>] unionfs_fault+0x22/0x5c
Jun 24 13:58:20 TN5 kernel: [ 3726.857523] PGD 400cf8067 PUD 415d9b067 PMD 0 
Jun 24 13:58:20 TN5 kernel: [ 3726.857527] Oops: 0000 [2] SMP 
Jun 24 13:58:20 TN5 kernel: [ 3726.857531] CPU: 6 
Jun 24 13:58:20 TN5 kernel: [ 3726.857533] Modules linked in: ipt_MASQUERADE iptable_nat nf_nat nf_conntrack_ipv4 nf_conntrack tunNRL vzethdev simfs vzrst vzcpt tun vzdquota xt_length ipt_ttl xt_tcpmss xt_TCPMSS iptable_mangle xt_multiport xt_limit autofs4 nfs lockd nfs_acl fuse sunrpc vznetdev vzmon vzdev xt_tcpudp ipt_REJECT iptable_filter ip_tables x_tables cpufreq_ondemand acpi_cpufreq freq_table dm_mirror dm_multipath dm_mod ipv6 iTCO_wdt pcspkr serio_raw iTCO_vendor_support i5000_edac edac_core bnx2 button sr_mod sg cdrom joydev usb_storage ata_piix libata shpchp megaraid_sas sd_mod scsi_mod ext3 jbd mbcache uhci_hcd ohci_hcd ehci_hcd
Jun 24 13:58:20 TN5 kernel: [ 3726.857589] Pid: 5781, comm: firefox-bin Tainted:  G      D 2.6.24-openvz.4.unionfs #2 ovz004
Jun 24 13:58:20 TN5 kernel: [ 3726.857592] RIP: 0010:[<ffffffff81119c66>]  [<ffffffff81119c66>] unionfs_fault+0x22/0x5c
Jun 24 13:58:20 TN5 kernel: [ 3726.857597] RSP: 0000:ffff81042d935ce8  EFLAGS: 00010282
Jun 24 13:58:20 TN5 kernel: [ 3726.857599] RAX: 0000000000000000 RBX: ffff8104048a63e0 RCX: ffffffff813fa120
Jun 24 13:58:20 TN5 kernel: [ 3726.857602] RDX: 0000000000000001 RSI: ffff81042d935d28 RDI: ffff8104048a63e0
Jun 24 13:58:20 TN5 kernel: [ 3726.857605] RBP: ffff81042d935cf8 R08: ffffffff8105e9ac R09: 0000000000000000
Jun 24 13:58:20 TN5 kernel: [ 3726.857608] R10: 0000000000000000 R11: ffffe2001a04e270 R12: ffff810400c3b000
Jun 24 13:58:20 TN5 kernel: [ 3726.857610] R13: 00000000086f9000 R14: 0000000000000000 R15: ffff81041f4de500
Jun 24 13:58:20 TN5 kernel: [ 3726.857614] FS:  0000000000000000(0000) GS:ffff81043d09f708(0063) knlGS:00000000b702a720
Jun 24 13:58:20 TN5 kernel: [ 3726.857617] CS:  0010 DS: 002b ES: 002b CR0: 000000008005003b
Jun 24 13:58:20 TN5 kernel: [ 3726.857619] CR2: 0000000000000028 CR3: 0000000400c3a000 CR4: 00000000000006e0
Jun 24 13:58:20 TN5 kernel: [ 3726.857622] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
Jun 24 13:58:20 TN5 kernel: [ 3726.857625] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Jun 24 13:58:20 TN5 kernel: [ 3726.857628] Process firefox-bin (pid: 5781, veid=2000, threadinfo ffff81042d934000, task ffff810400d66000)
Jun 24 13:58:20 TN5 kernel: [ 3726.857631] Stack:  ffff81042d935d48 ffff8104048a63e0 ffff81042d935d88 ffffffff8109a725
Jun 24 13:58:20 TN5 kernel: [ 3726.857637]  ffff810415d9b218 00000000086f9ec0 00ff810415cddc88 0000000000000000
Jun 24 13:58:20 TN5 kernel: [ 3726.857642]  0000000100000000 00000000000006b1 00000000086f9000 0000000000000000
Jun 24 13:58:20 TN5 kernel: [ 3726.857647] Call Trace:
Jun 24 13:58:20 TN5 kernel: [ 3726.857653]  [<ffffffff8109a725>] __do_fault+0x7d/0x4b3
Jun 24 13:58:20 TN5 kernel: [ 3726.857662]  [<ffffffff8109c387>] handle_mm_fault+0x268/0x980
Jun 24 13:58:20 TN5 kernel: [ 3726.857668]  [<ffffffff812a7a00>] do_page_fault+0x290/0x6d9
Jun 24 13:58:20 TN5 kernel: [ 3726.857675]  [<ffffffff812a7abc>] do_page_fault+0x34c/0x6d9
Jun 24 13:58:20 TN5 kernel: [ 3726.857683]  [<ffffffff810822b1>] audit_syscall_exit+0x311/0x332
Jun 24 13:58:20 TN5 kernel: [ 3726.857689]  [<ffffffff812a50a2>] lockdep_sys_exit_thunk+0x35/0x67
Jun 24 13:58:20 TN5 kernel: [ 3726.857695]  [<ffffffff812a5d7d>] error_exit+0x0/0xa9
Jun 24 13:58:20 TN5 kernel: [ 3726.857703] 
Jun 24 13:58:20 TN5 kernel: [ 3726.857704] 
Jun 24 13:58:20 TN5 kernel: [ 3726.857704] Code: 48 8b 48 28 48 85 c9 75 04 0f 0b eb fe 48 63 10 48 8b 40 18 
Jun 24 13:58:20 TN5 kernel: [ 3726.857716] RIP  [<ffffffff81119c66>] unionfs_fault+0x22/0x5c
Jun 24 13:58:20 TN5 kernel: [ 3726.857720]  RSP <ffff81042d935ce8>
Jun 24 13:58:20 TN5 kernel: [ 3726.857722] CR2: 0000000000000028
Jun 24 13:58:20 TN5 kernel: [ 3726.857734] ---[ end trace cda57437810fd849 ]---

Best Regards
Zhaohui Wang