[Unionfs] Kernel panic

[Fernando A. P. Gomes]

Hi,

 With the modifications that you required the dump is this:

[   68.498513] unionfs: lower dentry NULL (or error) for bindex = 3
[   68.510570] unionfs: lower dentry NULL (or error) for bindex = 2
[   68.522595] unionfs: lower dentry NULL (or error) for bindex = 1
[   77.800960] BUG: unable to handle kernel NULL pointer dereference at 
virtual address 00000000
[   77.818110]  printing eip:
[   77.823544] c0201875
[   77.827930] *pde = 00000000
[   77.833540] Oops: 0000 [#1]
[   77.839112] SMP
[   77.842856] CPU:    0
[   77.842857] EIP:    0060:[<c0201875>]    Not tainted VLI
[   77.842859] EFLAGS: 00010246   (2.6.23.1etfw #2)
[   77.867226] EIP is at __unionfs_check_dentry+0x63d/0x9b6
[   77.877829] eax: 00000000   ebx: 00000000   ecx: deb43e30   edx: dda63788
[   77.891381] esi: d85eec30   edi: ffffffff   ebp: dd747d00   esp: deb43e2c
[   77.904932] ds: 007b   es: 007b   fs: 00d8  gs: 0000  ss: 0068
[   77.916577] Process mingetty (pid: 2182, ti=deb43000 task=c14efa90 
task.ti=deb43000)
[   77.931688] Stack: c06105de dd747d00 dda63788 ffffffff 00000000 d85eec30 
deb43f08 00000000
[   77.948672]        00000000 00000000 00000001 00000000 de3c9c00 dda63788 
ffffffff 00000000
[   77.965654]        00000000 c054d735 c060f577 5a5a5a5a deb3ca78 d85eec30 
00000001 deb1bf80
[   77.982637] Call Trace:
[   77.987908]  [<c01f6aaa>] unionfs_setattr+0x43c/0x45a
[   77.998029]  [<c016eb1a>] notify_change+0x124/0x266
[   78.007802]  [<c015cac1>] chown_common+0xa6/0xb8
[   78.017055]  [<c0164d14>] __user_walk_fd+0x36/0x3e
[   78.026657]  [<c015cb09>] sys_chown+0x36/0x47
[   78.035391]  [<c016b8da>] dput+0x3b/0xf0
[   78.043259]  [<c015e75f>] __fput+0x128/0x152
[   78.051820]  [<c01025ea>] syscall_call+0x7/0xb
[   78.060728]  =======================
[   78.067867] Code: 00 00 8b 00 40 39 c3 0f 8d 9e 01 00 00 31 d2 83 7c 24 34 
00 89 d8 0f 94 c2 c1 e8 1f 09 c2 74 04 0f 0b eb fe 8b 54 24
[   78.107760] EIP: [<c0201875>] __unionfs_check_dentry+0x63d/0x9b6 SS:ESP 
0068:deb43e2c
[   78.123486] Kernel panic - not syncing: Fatal .

> How are the mounts configured? 

The mounts are this way:
none / unionfs 
rw,dirs=/.etfw_changes=rw:/cdrom/confs=ro:/cdrom/tmpdir/11=ro:/cdrom/tmpdir/10=ro:/cdrom/tmpdir/9=ro:/cdrom/tmpdir/8=ro:/cdrom/tmpdir/7=ro:/cdrom/tmpdir/6=ro:/cdrom/tmpdir/5=ro:/cdrom/tmpdir/4=ro:/cdrom/tmpdir/3=ro:/cdrom/tmpdir/2=ro:/cdrom/tmpdir/1=ro:/etfw=ro 
0 0

> Any chroot or  pivot_root stuff? 

Yes, I've a nash switchroot command like this:  switchroot /filesystem

> What commands are running when this oops happens? 

Now, It crashes most the time at startup, in mingetty, or agetty, or 
qmail-todo, or qmail-queue.

> Is  this a live-cd?  Can I get an image of this livecd?  (I asked before if
> you're using vmware and if so, can I get an image of your VM to reproduce
> the bug here).

I can try to get you this version that crashes. Wait news.

> The hardest part is always reproducing a bug: fixing it is relatively easy
> thereafter.

I know ;).

Regards,
Fernando Gomes