#7 Mounting loop device segfaults
I am having trouble getting the cryptoapi modules to
behave properly. I have loopback enabled in my Kernels
block devices. I emerge cryptoapi and re emerge
utils-linux with no obvious problems.
The modules load no problem. the only warnings are the
taint warnings. The modules I load are:
Code:
cipher-aes 31748 1
cryptoloop 1196 1
cryptoapi 2868 2 [cipher-aes cryptoloop]
When I set up /dev/loop0 to be a partition on one of my
HDD it seems to work, returning no errors (doesn't
return anything).
Code:
losetup -e aes -k 256 -p 0 /dev/loop0 /dev/sdb1 <
ext-backup.key
This seems to be OK. I get a process:
Code:
3968 ? SW 0:00 [loop0]
which I can't kill or attach a strace to (not sure if
that is by design or not). it will let me create the
file system on the loop device using
Code:
mke2fs -j /dev/loop0
this also seems to run with no problems. Now is the
annoying part. when I try and mount the loop device using:
Code:
mount -t ext3 /dev/loop0
I either get a segfault or no response. I can't kill
the process and ctrl-c does nothing. The only entry I
get in /var/log messages is:
Code:
Feb 3 14:12:29 trinity kernel: Unable to handle kernel
NULL pointer dereference at virtual address 00000094
Feb 3 14:12:29 trinity kernel: printing eip:
Feb 3 14:12:29 trinity kernel: c0324d88
Feb 3 14:12:29 trinity kernel: *pde = 00000000
Feb 3 14:12:29 trinity kernel: Oops: 0002
Feb 3 14:12:29 trinity kernel: CPU: 1
Feb 3 14:12:29 trinity kernel: EIP:
0010:[<c0324d88>] Tainted: P
Feb 3 14:12:29 trinity kernel: EFLAGS: 00010286
Feb 3 14:12:29 trinity kernel: eax: 00000000 ebx:
00000094 ecx: 00000094 edx: 00000001
Feb 3 14:12:29 trinity kernel: esi: 00000000 edi:
ca9d7400 ebp: cf93f4fc esp: ca9d1dc0
Feb 3 14:12:29 trinity kernel: ds: 0018 es: 0018
ss: 0018
Feb 3 14:12:29 trinity kernel: Process mount (pid:
3967, stackpage=ca9d1000)
Feb 3 14:12:29 trinity kernel: Stack: 00000078
cf93f4fc cf93f400 cbd7d400 c03169c9 00000000 fffffffb
cf93f400
Feb 3 14:12:29 trinity kernel: cf93f400
00000020 c0316a42 cf93f400 c022e320 c04f9ecf c022f3c0
00100000
Feb 3 14:12:29 trinity kernel: c0317c13
cf93f400 c04f9ecf c04ffa00 00000020 d4e86f64 00000080
0001f942
Feb 3 14:12:29 trinity kernel: Call Trace:
[<c03169c9>] [<c0316a42>] [<c0317c13>] [<c03184b8>]
[<c02e0f2e>]
Feb 3 14:12:29 trinity kernel: [<c02dfde5>]
[<c02e12f0>] [<c02f7b53>] [<c02f7ea4>] [<c02f8446>]
[<c029b087>]
Feb 3 14:12:29 trinity kernel:
Feb 3 14:12:29 trinity kernel: Code: f0 ff 8e 94 00 00
00 0f 88 3f 09 00 00 8b 44 24 18 89 44 24
I did get it to mount sucessfully twice last night. As
I thought the problem was now fixed I went home all
happy. When I get into work this morning it does not
work again.
something is obviously unhappy in the loop device, but
the question is what and how do I fix it?
Any suggestions would be gratefully appreciated.
Richard Hall
r.j.hall@rhul.ac.uk
