[ltt-dev] kernel panic

[Benjamin Poirier]

Hello,

I'm getting some panics at marker activation/disactivation with 0.188. Not all the time but often enough to be easy to reproduce. I just run `while true; do ltt-armall; ltt-disarmall; done` and wait a few seconds. Its quite similar to what I was seeing a few months ago. Here it goes:

[   31.877009] BUG: unable to handle kernel NULL pointer dereference at 00000001
[   31.877044] IP: [<c1018892>] arch_imv_update+0x7f/0x201
[   31.877044] *pde = 00000000 
[   31.877044] Oops: 0002 [#1] SMP 
[   31.877044] LTT NESTING LEVEL : 0
[   31.877044] last sysfs file: /sys/kernel/uevent_seqnum
[   31.877044] 
[   31.877044] Pid: 3406, comm: ltt-disarmall Not tainted (2.6.32.4 #135)  
[   31.877044] EIP: 0060:[<c1018892>] EFLAGS: 00010086 CPU: 0
[   31.877044] EIP is at arch_imv_update+0x7f/0x201
[   31.877044] EAX: 00000001 EBX: c17209a8 ECX: 00000000 EDX: f6bffe40
[   31.877044] ESI: 00000000 EDI: f6bffe40 EBP: f6bffe28 ESP: f6bffe18
[   31.877044]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
[   31.877044] Process ltt-disarmall (pid: 3406, ti=f6bfe000 task=f6bf8f60 task.ti=f6bfe000)
[   31.877044] Stack:
[   31.877044]  000000ef c17209a8 00000000 fff20c40 f6bffe38 c1015777 00000000 f6bffec0
[   31.877044] <0> f6bffe9c c10034b6 00000000 f6bffebf 00000001 f6bffec0 fff20c40 f6bffe9c
[   31.877044] <0> 000006cc 0000007b 0000007b 000000d8 00000000 ffffff10 c10074d3 00000060
[   31.877044] Call Trace:
[   31.877044]  [<c1015777>] ? smp_apic_timer_interrupt+0x44/0x9c
[   31.877044]  [<c10034b6>] ? apic_timer_interrupt+0x2a/0x30
[   31.877044]  [<c10074d3>] ? text_poke+0x13f/0x14a
[   31.877044]  [<c1014c3f>] ? trace_irq_entry+0x10/0x38
[   31.877044]  [<c1014c41>] ? trace_irq_entry+0x12/0x38
[   31.877044]  [<c1018993>] ? arch_imv_update+0x180/0x201
[   31.877044]  [<c1014c3f>] ? trace_irq_entry+0x10/0x38
[   31.877044]  [<c106f615>] ? imv_update_range+0x3e/0x8c
[   31.877044]  [<c106f675>] ? core_imv_update+0x12/0x15
[   31.877044]  [<c1071294>] ? tracepoint_update_probes+0x17/0x19
[   31.877044]  [<c1071312>] ? tracepoint_probe_update_all+0x7c/0xb4
[   31.877044]  [<c10702eb>] ? marker_update_probes+0x17/0x1e
[   31.877044]  [<c1070435>] ? marker_probe_unregister+0x4e/0x7c
[   31.877044]  [<c11819df>] ? ltt_marker_disconnect+0x89/0xd4
[   31.877044]  [<c1186760>] ? marker_enable_write+0x9d/0xb9
[   31.877044]  [<c11866c3>] ? marker_enable_write+0x0/0xb9
[   31.877044]  [<c10ae061>] ? vfs_write+0x84/0xdf
[   31.877044]  [<c10ae191>] ? sys_write+0x3c/0x87
[   31.877044]  [<c1002b54>] ? sysenter_do_call+0x12/0x22
[   31.877044] Code: 85 8e 01 00 00 80 7d da 0a 76 0f ba f0 00 00 00 b8 9c b3 5a c1 e8 03 8f 01 00 eb 18 8d b6 00 00 00 00 8d bc 27 00 00 00 00 b0 01 <01> 00 04 00 0d 2c 43 76 cc b8 90 88 01 c1 ba 9b 88 01 c1 89 15 
[   31.877044] EIP: [<c1018892>] arch_imv_update+0x7f/0x201 SS:ESP 0068:f6bffe18
[   31.877044] CR2: 0000000000000001
[   31.877044] ---[ end trace f0cbc16b434adca6 ]---
[   31.877044] Kernel panic - not syncing: Fatal exception in interrupt
[   31.877044] Pid: 3406, comm: ltt-disarmall Tainted: G      D    2.6.32.4 #135
[   31.877044] Call Trace:
[   31.877044]  [<c146ec5e>] panic+0x5b/0xfd
[   31.877044]  [<c1005c50>] oops_end+0x8a/0xa9
[   31.877044]  [<c101c6b4>] no_context+0x10c/0x116
[   31.877044]  [<c101c844>] __bad_area_nosemaphore+0x186/0x18e
[   31.877044]  [<c118c842>] ? put_dec+0x2a/0xff
[   31.877044]  [<c1048b5b>] ? notifier_call_chain+0x2b/0x4a
[   31.877044]  [<c101c859>] bad_area_nosemaphore+0xd/0x10
[   31.877044]  [<c101caca>] do_page_fault+0x11d/0x2e5
[   31.877044]  [<c101c9ad>] ? do_page_fault+0x0/0x2e5
[   31.877044]  [<c1470a66>] error_code+0x66/0x6c
[   31.877044]  [<c101c9ad>] ? do_page_fault+0x0/0x2e5
[   31.877044]  [<c1018892>] ? arch_imv_update+0x7f/0x201
[   31.877044]  [<c1015777>] smp_apic_timer_interrupt+0x44/0x9c
[   31.877044]  [<c10034b6>] apic_timer_interrupt+0x2a/0x30
[   31.877044]  [<c10074d3>] ? text_poke+0x13f/0x14a
[   31.877044]  [<c1014c3f>] ? trace_irq_entry+0x10/0x38
[   31.877044]  [<c1014c41>] ? trace_irq_entry+0x12/0x38
[   31.877044]  [<c1018993>] arch_imv_update+0x180/0x201
[   31.877044]  [<c1014c3f>] ? trace_irq_entry+0x10/0x38
[   31.877044]  [<c106f615>] imv_update_range+0x3e/0x8c
[   31.877044]  [<c106f675>] core_imv_update+0x12/0x15
[   31.877044]  [<c1071294>] tracepoint_update_probes+0x17/0x19
[   31.877044]  [<c1071312>] tracepoint_probe_update_all+0x7c/0xb4
[   31.877044]  [<c10702eb>] marker_update_probes+0x17/0x1e
[   31.877044]  [<c1070435>] marker_probe_unregister+0x4e/0x7c
[   31.877044]  [<c11819df>] ltt_marker_disconnect+0x89/0xd4
[   31.877044]  [<c1186760>] marker_enable_write+0x9d/0xb9
[   31.877044]  [<c11866c3>] ? marker_enable_write+0x0/0xb9
[   31.877044]  [<c10ae061>] vfs_write+0x84/0xdf
[   31.877044]  [<c10ae191>] sys_write+0x3c/0x87
[   31.877044]  [<c1002b54>] sysenter_do_call+0x12/0x22

Tell me if you need more info.

-Ben