Null Pointer Dereference

[robsee]

Hi,

The storage got pulled out from underneath my zpool and I had to
forcefully reboot the machine. After I rebooted, I get the following
error when it tried to mount one zfs volume:


[ 67.121735] BUG: unable to handle kernel NULL pointer dereference
at (null)
[ 67.121771] IP: [<(null)>] (null)
[ 67.121787] PGD 12a670067 PUD 12aeb4067 PMD 0
[ 67.121812] Oops: 0010 [#1] SMP
[ 67.121830] last sysfs file: /sys/devices/virtual/misc/zfs/uevent
[ 67.121851] CPU 0
[ 67.121860] Modules linked in: lzfs zfs(P) zcommon(P) znvpair(P)
zavl(P) zlib_deflate zunicode(P) spl nfsd exportfs nfs lockd fscache
nfs_acl auth_rpcgss sunrpc snd_hda_codec_intelhdmi
snd_hda_codec_realtek i915 snd_hda_intel drm_kms_helper snd_hda_codec
snd_hwdep snd_pcm snd_timer asus_atk0110 psmouse serio_raw drm lp snd
i2c_algo_bit soundcore snd_page_alloc parport video output intel_agp
usbhid hid atl1e ahci libahci
[ 67.122092]
[ 67.122101] Pid: 2055, comm: zfs Tainted: P 2.6.35-22-
server #35-Ubuntu P5G43T-M PRO/System Product Name
[ 67.122133] RIP: 0010:[<0000000000000000>] [<(null)>] (null)
[ 67.122155] RSP: 0018:ffff8801083d9a10 EFLAGS: 00010246
[ 67.122174] RAX: ffffffffa04c63e0 RBX: ffffc9002634e308 RCX:
ffffffffffffff40
[ 67.122198] RDX: 0000000000000000 RSI: ffffc9002efe9000 RDI:
ffff8800cb192000
[ 67.122221] RBP: ffff8801083d9a48 R08: ffffc9002efe90c0 R09:
f154af9b729b480b
[ 67.122244] R10: 0000000000000008 R11: dead000000200200 R12:
ffff8800cb082800
[ 67.122267] R13: ffff8801083d9c88 R14: 0000000000000014 R15:
00000000000000c0
[ 67.122291] FS: 00007f04b80f8b40(0000) GS:ffff880001e00000(0000)
knlGS:0000000000000000
[ 67.122318] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 67.122337] CR2: 0000000000000000 CR3: 000000012b21e000 CR4:
00000000000406f0
[ 67.122361] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 67.122384] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7:
0000000000000400
[ 67.122930] Process zfs (pid: 2055, threadinfo ffff8801083d8000,
task ffff8801090396e0)
[ 67.123497] Stack:
[ 67.124069] ffffffffa0499370 ffff8801083d9a48 ffffc9002634e308
ffffc9002634e308
[ 67.124101] <0> 00000000000000c0 ffff8800cb082800 0000000000000014
ffff8801083d9c78
[ 67.124723] <0> ffffffffa049bef1 ffff880100000040 ffff8801083d9c40
ffff8801083d9c18
[ 67.125992] Call Trace:
[ 67.126677] [<ffffffffa0499370>] ? zil_replay_log_record
+0xd0/0x190 [zfs]
[ 67.127375] [<ffffffffa049bef1>] zil_parse+0x431/0x800 [zfs]
[ 67.128082] [<ffffffffa0498ff0>] ? zil_incr_blks+0x0/0x20 [zfs]
[ 67.128806] [<ffffffffa04992a0>] ? zil_replay_log_record+0x0/0x190
[zfs]
[ 67.129543] [<ffffffffa049ca61>] zil_replay+0xb1/0x100 [zfs]
[ 67.130292] [<ffffffffa048ecfd>] zfsvfs_setup+0x13d/0x160 [zfs]
[ 67.131053] [<ffffffffa048ee8e>] zfs_domount+0x16e/0x180 [zfs]
[ 67.131624] [<ffffffffa0531a32>] lzfs_fill_super+0xc2/0x300 [lzfs]
[ 67.131624] [<ffffffff81155e98>] ? sget+0x1c8/0x230
[ 67.131624] [<ffffffff811549f0>] ? set_anon_super+0x0/0x120
[ 67.131624] [<ffffffffa0531970>] ? lzfs_fill_super+0x0/0x300
[lzfs]
[ 67.131624] [<ffffffff8115601f>] get_sb_nodev+0x5f/0xb0
[ 67.131624] [<ffffffffa0531147>] lzfs_get_sb+0x57/0x1e0 [lzfs]
[ 67.131624] [<ffffffff81155a1a>] vfs_kern_mount+0x8a/0x1f0
[ 67.131624] [<ffffffff81155bf2>] do_kern_mount+0x52/0x130
[ 67.131624] [<ffffffff8159ec4e>] ? _lock_kernel+0x4e/0xa0
[ 67.131624] [<ffffffff81170f2a>] do_mount+0x20a/0x260
[ 67.131624] [<ffffffff81171010>] sys_mount+0x90/0xe0
[ 67.131624] [<ffffffff8100a0f2>] system_call_fastpath+0x16/0x1b
[ 67.131624] Code: Bad RIP value.
[ 67.131624] RIP [<(null)>] (null)
[ 67.131624] RSP <ffff8801083d9a10>
[ 67.131624] CR2: 0000000000000000
[ 67.144713] ---[ end trace f764bd040d1a4f1f ]---

Any suggestions ?

Thanks,
-Rob

[Prasad Joshi]

This needs to be solved. We will try to reproduce the problem on our end. 

Thanks a lot for finding this Bug.

Regards,

Prasad

 

Thanks,
-Rob