[Unionfs] RHEL 2.6.9 hangs with unionfs-1.1.5

[Benoit Guillon]

Hello,

Sorry to bother you again with my problem. Here is another kernel panic 
trace (a different one). I had no answer to the previous mail; does it 
mean that 1.1.5 is not maintained ? I must stay with 2.6.9 kernel, so 
what should I do ? It becomes a showstopper for me, so any hints to 
workaround or fix it is really welcome. I have no easy reproducible 
configuration, but I can do any testing that may help understanding the 
problem.

Nov 27 14:36:35 node1 kernel: Unable to handle kernel paging request at 
virtual address ffffff9c
Nov 27 14:36:35 node1 kernel:  printing eip:
Nov 27 14:36:35 node1 kernel: e07bf9f6
Nov 27 14:36:35 node1 kernel: *pde = 2d6e6f6e
Nov 27 14:36:35 node1 kernel: Oops: 0000 [#1]
Nov 27 14:36:35 node1 kernel: SMP
Nov 27 14:36:35 node1 kernel: Modules linked in: unionfs(U) i915 nfsd 
exportfs lockd nfs_acl sunrpc i2c_dev i2c_core poweroff(U) allocator(U) 
dm_mirror dm_mod button battery ac md5 ipv6 joydev uhci_hcd ehci_hcd 
hw_random snd_intel8x0 snd_ac97_codec snd_pcm_oss snd_mixer_oss snd_pcm 
snd_timer snd_page_alloc snd_mpu401_uart snd_rawmidi snd_seq_device snd 
soundcore tg3 8139too mii floppy ext3 jbd ata_piix libata sd_mod scsi_mod
Nov 27 14:36:35 node1 kernel: CPU:    0
Nov 27 14:36:35 node1 kernel: EIP:    0060:[<e07bf9f6>]    Tainted: 
P      VLI
Nov 27 14:36:35 node1 kernel: EFLAGS: 00010246   (2.6.9-34.ELsmp)
Nov 27 14:36:35 node1 kernel: EIP is at do_get_dentry+0xb56/0xd70 [unionfs]
Nov 27 14:36:35 node1 kernel: eax: 00000000   ebx: d71e0ba4   ecx: 
00000000   edx: c038ff80
Nov 27 14:36:35 node1 kernel: esi: 00000001   edi: 00000000   ebp: 
ffffff8c   esp: d5158e30
Nov 27 14:36:35 node1 kernel: ds: 007b   es: 007b   ss: 0068
Nov 27 14:36:35 node1 kernel: Process nfsd (pid: 2992, 
threadinfo=d5158000 task=de844b30)
Nov 27 14:36:35 node1 kernel: Stack: e07e86c0 e07e767c 00000233 00000004 
e07e89d0 e07f0ae0 e07e767c e07e86c0
Nov 27 14:36:35 node1 kernel:        00000233 df0ba474 0008ce37 0008ce1a 
00000002 e07be00f 00000002 00000003
Nov 27 14:36:35 node1 kernel:        dee58000 ffffff8c 00000000 000002dd 
df23a400 00000002 00000012 dee58ff9
Nov 27 14:36:35 node1 kernel: Call Trace:
Nov 27 14:36:35 node1 kernel:  [<e07be00f>] 
unionfs_destroy_inode+0xbf/0xd0 [unionfs]
Nov 27 14:36:35 node1 kernel:  [<e07c1052>] 
unionfs_decode_fh+0x132/0x164 [unionfs]
Nov 27 14:36:35 node1 kernel:  [<e07c0f20>] unionfs_decode_fh+0x0/0x164 
[unionfs]
Nov 27 14:36:35 node1 kernel:  [<e0418067>] fh_verify+0x3f5/0x5f6 [nfsd]
Nov 27 14:36:35 node1 kernel:  [<e0417bb8>] nfsd_acceptable+0x0/0xba [nfsd]
Nov 27 14:36:35 node1 kernel:  [<e03b4383>] 
svcauth_unix_set_client+0xa7/0xb5 [sunrpc]
Nov 27 14:36:35 node1 kernel:  [<e0421142>] nfsd3_proc_getattr+0x6f/0x77 
[nfsd]
Nov 27 14:36:35 node1 kernel:  [<e0422d77>] 
nfs3svc_decode_fhandle+0x0/0x8f [nfsd]
Nov 27 14:36:35 node1 kernel:  [<e0416681>] nfsd_dispatch+0xba/0x16d [nfsd]
Nov 27 14:36:35 node1 kernel:  [<e03b155b>] svc_process+0x432/0x6d7 [sunrpc]
Nov 27 14:36:35 node1 kernel:  [<e041645a>] nfsd+0x1cc/0x339 [nfsd]
Nov 27 14:36:35 node1 kernel:  [<e041628e>] nfsd+0x0/0x339 [nfsd]
Nov 27 14:36:35 node1 kernel:  [<c01041f5>] kernel_thread_helper+0x5/0xb
Nov 27 14:36:35 node1 kernel: Code: 24 44 8d 77 01 89 74 24 5c b8 2f 00 
00 00 88 c4 ac 38 e0 74 09 84 c0 75 f7 be 01 00 00 00 89 f0 48 85 c0 89 
c7 0f 85 46 ff ff ff <8b> 75 10 31 c9 ba 6b 00 00 00 b8 de a7 7e e0 e8 
2b 05 96 df 8d
Nov 27 14:36:35 node1 kernel:  <0>Fatal exception: panic in 5 seconds

Thanks,

Benoit Guillon wrote:

> Hello,
>
> I use unionfs to serve some diskless nodes. Its a 2.6.9-34.EL kernel 
> with unionfs-1.1.5 that does the mount and exports the mounted file 
> system. The mount is ok, and the diskless nodes can switchroot on this 
> NFS mounted file system.
>
> The problem is that often the kernel hangs and freezes completely. 
> I've put the debug level to 99, and before the freezing I have the 
> following traces showing a kernel oops:

-- 
Benoît Guillon                guillon at thalescomputers.fr
TRT/SML                       tel. : 33 (0)4 98 16 33 90
 
THALES RESEARCH & TECHNOLOGY