Hi there,
I just found a segfaulting tapdisk2 process which led into a kernel oops.
[1527071.169682] tapdisk2[26548]: segfault at 7fffd324cfe8 ip 000000000040837f
sp 00007fffd324cff0 error 6 in tapdisk2[400000+38000]
[1527071.220104] BUG: unable to handle kernel NULL pointer dereference at
0000000000000048
[1527071.220170] IP: [<ffffffff810ce73c>] apply_to_page_range+0x47/0x2f3
[1527071.220210] PGD 1e9a9067 PUD 1e9a8067 PMD 0
[1527071.220250] Oops: 0000 [#1] SMP
[1527071.220282] last sysfs file: /sys/devices/virtual/blktap2/blktap0/remove
[1527071.220315] CPU 0
[1527071.220340] Modules linked in: xt_state xt_physdev tun ip6table_filter
ip6_tables nfs
lockd fscache nfs_acl auth_rpcgss sunrpc bridge stp ipt_REJECT xt_tcpudp
iptable_nat
nf_nat nf_conntrack_ipv4 nf_conntrack nf_defrag_ipv4 iptable_filter ip_tables
x_tables
blktap xen_blkfront xenfs xen_evtchn quota_v2 quota_tree psmouse evdev
serio_raw snd_pcsp
i2c_i801 rng_core snd_pcm snd_timer i2c_core iTCO_wdt iTCO_vendor_support snd
soundcore
snd_page_alloc i5000_edac edac_core i5k_amb button processor acpi_processor
shpchp
pci_hotplug ext3 jbd sd_mod crc_t10dif uhci_hcd ehci_hcd mptsas usbcore
nls_base mptscsih
mptbase scsi_transport_sas tg3 libphy thermal fan thermal_sys dm_snapshot
dm_mirror
dm_region_hash dm_log dm_mod
[1527071.220854] Pid: 26548, comm: tapdisk2 Not tainted 2.6.32-ucs48-xen-amd64
#1 PRIMERGY
BX620 S4
[1527071.220904] RIP: e030:[<ffffffff810ce73c>]
[<ffffffff810ce73c>]
apply_to_page_range+0x47/0x2f3
[1527071.220958] RSP: e02b:ffff880000d11b58 EFLAGS: 00010202
[1527071.224008] RAX: 0000000000000880 RBX: ffff88001e12c000 RCX:
ffff88001e12d000
[1527071.224008] RDX: 0000000000000000 RSI: ffff88001e12c000 RDI:
0000000000000000
[1527071.224008] RBP: ffff88001f31ad30 R08: 0000000000000000 R09:
ffff88001f907840
[1527071.224008] R10: ffffffff81324b0a R11: 0000000000000000 R12:
0000000000000000
[1527071.224008] R13: ffff88001f31ad30 R14: ffff88001d82c800 R15:
0000000000000000
[1527071.224008] FS: 00007fa53151a730(0000) GS:ffff8800035cb000(0000)
knlGS:0000000000000000
[1527071.224008] CS: e033 DS: 0000 ES: 0000 CR0: 000000008005003b
[1527071.224008] CR2: 0000000000000048 CR3: 000000001e9ae000 CR4:
0000000000002660
[1527071.224008] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[1527071.224008] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:
0000000000000400
[1527071.224008] Process tapdisk2 (pid: 26548, threadinfo ffff880000d10000,
task
ffff88001dd41c40)
[1527071.224008] Stack:
[1527071.224008] 0000000000000040 ffff88001b189180 0000000000000000
0000000000000000
[1527071.224008] <0> ffffffffa02a7ee8 0000000000000000 ffffffff8100ece2
ffff88001eb0f240
[1527071.224008] <0> ffff88001e12d000 0000000000000000 0000000000000000
ffff88001eb0f240
[1527071.224008] Call Trace:
[1527071.224008] [<ffffffffa02a7ee8>] ? blktap_umap_uaddr_fn+0x0/0x59
[blktap]
[1527071.224008] [<ffffffff8100ece2>] ? check_events+0x12/0x20
[1527071.224008] [<ffffffffa02a92a5>] ?
blktap_device_end_request+0xbd/0x145
[blktap]
[1527071.224008] [<ffffffffa02a7743>] ? blktap_ring_vm_close+0x60/0xd1
[blktap]
[1527071.224008] [<ffffffff810d1394>] ? remove_vma+0x2c/0x72
[1527071.224008] [<ffffffff810d1503>] ? exit_mmap+0x129/0x148
[1527071.224008] [<ffffffff8104cc75>] ? mmput+0x3c/0xdf
[1527071.224008] [<ffffffff8105087a>] ? exit_mm+0x102/0x10d
[1527071.224008] [<ffffffff8132448a>] ? _spin_lock_irq+0x7/0x22
[1527071.224008] [<ffffffff810522a3>] ? do_exit+0x1f8/0x6c6
[1527071.224008] [<ffffffff8105d5bb>] ? __dequeue_signal+0xfb/0x124
[1527071.224008] [<ffffffff8100eccf>] ? xen_restore_fl_direct_end+0x0/0x1
[1527071.224008] [<ffffffff810e7ebd>] ? kmem_cache_free+0x72/0xa3
[1527071.224008] [<ffffffff810527e7>] ? do_group_exit+0x76/0x9d
[1527071.224008] [<ffffffff8105f0c5>] ? get_signal_to_deliver+0x318/0x343
[1527071.224008] [<ffffffff8101104f>] ? do_notify_resume+0x87/0x73f
[1527071.224008] [<ffffffff810d157d>] ? expand_downwards+0x5b/0x15b
[1527071.224008] [<ffffffff8132694b>] ? do_page_fault+0x1f5/0x2fc
[1527071.224008] [<ffffffff810125dc>] ? retint_signal+0x48/0x8c
[1527071.224008] Code: 48 89 4c 24 20 4c 89 44 24 18 48 89 54 24 40 72 04 0f
0b eb fe 48
8b 54 24 28 48 89 f0 48 8b 4c 24 40 48 c1 e8 24 25 f8 0f 00 00 <48> 8b 52
48
48 ff c9 48
89 0c 24 48 01 d0 48 89 44 24 30 48 b8
[1527071.224008] RIP [<ffffffff810ce73c>] apply_to_page_range+0x47/0x2f3
[1527071.224008] RSP <ffff880000d11b58>
[1527071.224008] CR2: 0000000000000048
[1527071.224008] ---[ end trace 7b79961eab7bea21 ]---
Kernel: current 2.6.32-ucs48-xen-amd64 from debian-based UCS 2.4-4
Unfortunately I don''t have any further information towards that
process.
Neither do I know which image the tapdisk-process handled nor can I find any
coherences to any DomU''s shutting down or starting...
In kern.og I can find several lines with i/o errors before the segfault:
[1526966.852693] end_request: I/O error, dev tda, sector 62916088
I can reproduce such messages by removing an image while the DomU is running.
But till now I didn''t get the segfault or kernel oops again. I also
tried to
shut the DomU down or migrate it (...with lost image)...
Perhaps another important information: The images are located at a NetApp
storage over NFS in that environment.
Does anybody also got that Oops till now or has further information for me?
Kind regards,
Tim
--
Tim Petersen
Support Engineer
Univention GmbH
Linux for your business
Mary-Somerville-Str.1
28359 Bremen
Tel. : +49 421 22232-0
Fax : +49 421 22232-99
petersen@univention.de
http://www.univention.de
Geschäftsführer: Peter H. Ganten
HRB 20755 Amtsgericht Bremen
Steuer-Nr.: 71-597-02876
