Kernel bug found by chef-client on ubuntu 11.04 ec2

gistfile1.txt

[119832.732086] BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
[119832.732111] IP: [<ffffffff81053527>] pick_next_task_fair+0xa7/0x1a0
[119832.732124] PGD 1cee6f067 PUD 1cd5e7067 PMD 0 
[119832.732132] Oops: 0000 [#1] SMP 
[119832.732137] last sysfs file: /sys/devices/system/cpu/cpu1/cache/index2/shared_cpu_map
[119832.732145] CPU 1 
[119832.732147] Modules linked in: acpiphp raid456 async_pq async_xor xor async_memcpy async_raid6_recov raid10 raid6_pq async_tx raid1 raid0 multipath linear
[119832.732172] 
[119832.732177] Pid: 7896, comm: chef-client Not tainted 2.6.38-8-virtual #42-Ubuntu  
[119832.732186] RIP: e030:[<ffffffff81053527>]  [<ffffffff81053527>] pick_next_task_fair+0xa7/0x1a0
[119832.732196] RSP: e02b:ffff880127e9f848  EFLAGS: 00010046
[119832.732201] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[119832.732208] RDX: ffff8801dffa3b00 RSI: 0000000000000000 RDI: 0000000000000000
[119832.732214] RBP: ffff880127e9f878 R08: ffff8801dff83a40 R09: 0000000000000000
[119832.732220] R10: 0000000000000001 R11: 0000000000000001 R12: ffff8801cde35900
[119832.732226] R13: 0000000000000000 R14: 0000000000000000 R15: ffff8801dffa3b00
[119832.732236] FS:  00007fb415914700(0000) GS:ffff8801dff90000(0000) knlGS:0000000000000000
[119832.732242] CS:  e033 DS: 0000 ES: 0000 CR0: 000000008005003b
[119832.732247] CR2: 0000000000000038 CR3: 00000001cf2f5000 CR4: 0000000000002660
[119832.732254] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[119832.732260] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000000
[119832.732267] Process chef-client (pid: 7896, threadinfo ffff880127e9e000, task ffff8801000cdb00)
[119832.732274] Stack:
[119832.732277]  ffff8801cd69ba00 ffff8801dffa3b00 0000000000000001 ffff8801000cde98
[119832.732287]  0000000000000008 ffff8801cdf5ad80 ffff880127e9f8f8 ffffffff815d99a1
[119832.732297]  ffff880127e9ffd8 ffff880127e9e000 0000000000013b00 ffff8801000cdea0
[119832.732306] Call Trace:
[119832.732315]  [<ffffffff815d99a1>] schedule+0x171/0x760
[119832.732321]  [<ffffffff815db15d>] schedule_hrtimeout_range_clock+0x14d/0x170
[119832.732329]  [<ffffffff815dc13e>] ? _raw_spin_unlock_irqrestore+0x1e/0x30
[119832.732336]  [<ffffffff810875ee>] ? add_wait_queue+0x4e/0x60
[119832.732342]  [<ffffffff815db193>] schedule_hrtimeout_range+0x13/0x20
[119832.732351]  [<ffffffff81176209>] poll_schedule_timeout+0x49/0x70
[119832.732358]  [<ffffffff81176d0e>] do_select+0x4ae/0x5f0
[119832.732364]  [<ffffffff811762e0>] ? __pollwait+0x0/0xf0
[119832.732369]  [<ffffffff811763d0>] ? pollwake+0x0/0x60
[119832.732377]  [<ffffffff81038d15>] ? pvclock_clocksource_read+0x55/0xd0
[119832.732384]  [<ffffffff810567a6>] ? check_preempt_wakeup+0x1b6/0x280
[119832.732392]  [<ffffffff8100761f>] ? __raw_callee_save_xen_restore_fl+0x11/0x1e
[119832.732400]  [<ffffffff815dc13e>] ? _raw_spin_unlock_irqrestore+0x1e/0x30
[119832.732407]  [<ffffffff8105efe4>] ? try_to_wake_up+0x244/0x3e0
[119832.732413]  [<ffffffff8105f192>] ? default_wake_function+0x12/0x20
[119832.732419]  [<ffffffff81038d15>] ? pvclock_clocksource_read+0x55/0xd0
[119832.732425]  [<ffffffff81176ffc>] core_sys_select+0x1ac/0x2f0
[119832.732432]  [<ffffffff810535a1>] ? pick_next_task_fair+0x121/0x1a0
[119832.732438]  [<ffffffff8100761f>] ? __raw_callee_save_xen_restore_fl+0x11/0x1e
[119832.732446]  [<ffffffff81004686>] ? xen_mc_flush+0x96/0x1d0
[119832.732451]  [<ffffffff81003f1b>] ? xen_write_cr0+0x3b/0x90
[119832.732458]  [<ffffffff8117730f>] sys_select+0x3f/0x100
[119832.732463]  [<ffffffff8100763d>] ? __raw_callee_save_xen_irq_disable+0x11/0x1e
[119832.732472]  [<ffffffff8100bfc2>] system_call_fastpath+0x16/0x1b
[119832.732477] Code: 8e e7 00 00 00 49 8b 44 24 60 48 85 c0 74 14 48 8b 78 50 4c 89 ee e8 e9 bb ff ff 85 c0 0f 8e d9 00 00 00 48 89 df e8 b9 b7 ff ff <44> 8b 53 38 45 85 d2 0f 85 84 00 00 00 49 8b 44 24 70 48 8b 80 
[119832.732541] RIP  [<ffffffff81053527>] pick_next_task_fair+0xa7/0x1a0
[119832.732549]  RSP <ffff880127e9f848>
[119832.732552] CR2: 0000000000000038
[119832.732561] ---[ end trace 98be7009e5df416b ]---
Xen Minimal OS!
  start_info: 0x1890000(VA)
    nr_pages: 0x1e0000
  shared_inf: 0x00faf000(MA)
     pt_base: 0x1893000(VA)
nr_pt_frames: 0x11
    mfn_list: 0x990000(VA)
   mod_start: 0x0(VA)
     mod_len: 0
       flags: 0x0
    cmd_line:  root=/dev/sda1 ro 4
  stack:      0x94f860-0x96f860
MM: Init
      _text: 0x0(VA)
     _etext: 0x5ff6d(VA)
   _erodata: 0x78000(VA)
     _edata: 0x80b00(VA)
stack start: 0x94f860(VA)
       _end: 0x98fe68(VA)
  start_pfn: 18a7
    max_pfn: 1e0000
Mapping memory range 0x1c00000 - 0x1e0000000
setting 0x0-0x78000 readonly
skipped 0x1000
MM: Initialise page allocator for 27a0000(27a0000)-1e0000000(1e0000000)
MM: done
Demand map pfns at 1e0001000-21e0001000.
Heap resides at 21e0002000-41e0002000.
Initialising timer interface
Initialising console ... done.
gnttab_table mapped at 0x1e0001000.
Initialising scheduler
Thread "Idle": pointer: 0x21e0002010, stack: 0x36f0000
Initialising xenbus
Thread "xenstore": pointer: 0x21e00027c0, stack: 0x3700000
Dummy main: start_info=0x96f960
Thread "main": pointer: 0x21e0002f70, stack: 0x3710000
"main" "root=/dev/sda1" "ro" "4" 
vbd 2049 is hd0
******************* BLKFRONT for device/vbd/2049 **********


backend at /local/domain/0/backend/vbd/28/2049
Failed to read /local/domain/0/backend/vbd/28/2049/feature-barrier.
Failed to read /local/domain/0/backend/vbd/28/2049/feature-flush-cache.
16777216 sectors of 512 bytes
**************************
vbd 2064 is hd1
******************* BLKFRONT for device/vbd/2064 **********


backend at /local/domain/0/backend/vbd/28/2064
Failed to read /local/domain/0/backend/vbd/28/2064/feature-barrier.
Failed to read /local/domain/0/backend/vbd/28/2064/feature-flush-cache.
880732160 sectors of 512 bytes
**************************
vbd 2161 is hd2
******************* BLKFRONT for device/vbd/2161 **********


backend at /local/domain/0/backend/vbd/28/2161
Failed to read /local/domain/0/backend/vbd/28/2161/feature-barrier.
Failed to read /local/domain/0/backend/vbd/28/2161/feature-flush-cache.
209715200 sectors of 512 bytes
**************************
vbd 2162 is hd3
******************* BLKFRONT for device/vbd/2162 **********


backend at /local/domain/0/backend/vbd/28/2162
Failed to read /local/domain/0/backend/vbd/28/2162/feature-barrier.
Failed to read /local/domain/0/backend/vbd/28/2162/feature-flush-cache.
209715200 sectors of 512 bytes
**************************
vbd 2163 is hd4
******************* BLKFRONT for device/vbd/2163 **********


backend at /local/domain/0/backend/vbd/28/2163
Failed to read /local/domain/0/backend/vbd/28/2163/feature-barrier.
Failed to read /local/domain/0/backend/vbd/28/2163/feature-flush-cache.
209715200 sectors of 512 bytes
**************************
vbd 2164 is hd5
******************* BLKFRONT for device/vbd/2164 **********


backend at /local/domain/0/backend/vbd/28/2164
Failed to read /local/domain/0/backend/vbd/28/2164/feature-barrier.
Failed to read /local/domain/0/backend/vbd/28/2164/feature-flush-cache.
209715200 sectors of 512 bytes
**************************

uname

uname -a
Linux hostname 2.6.38-8-virtual #42-Ubuntu SMP Mon Apr 11 04:06:34 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux