Hi,

I've got a reproducible oops when using cryptoloop on vanilla 2.6.0,
2.6.1 and 2.6.2 (2.4.* works fine).

Way to reproduce:
dd if=/dev/urandom of=crypto bs=1024 count=some_size
losetup -e some_cipher /dev/loop0 crypto
#Any of those commands causes oops and hard lockup:
cp /dev/loop0 /dev/null
mkreiserfs /dev/loop0
mkfs.ext2 /dev/loop0

Loop without cryptoapi works fine:
dd if=/dev/urandom of=crypto bs=1024 count=some_size
losetup /dev/loop0 crypto
cp /dev/loop0 /dev/null
#ok, no oops

Sometimes it writes 10KB sometimes 10MB before it oopses. It may be just
coincidence but without HT enabled it lived longer. As it locks hard 
after oops I don't have oops messages in log. I have written down some:

1.
init: panic: Segmentation violation at 0x40126A83! Sleeping for 30 sec...

2.
Unable to handle kernel paging request at virtual address 87550c8a
EIP is at cleanup_bitmap_list +0x48/0x68
...

3.
Unable to handle kernel paging request at virtual address
EIP IS AT get_cnode +0x61/0x94
...

4.
Unable to handle kernel paging request at virtual address faad7260
EIP is at journal_mark_dirty +0x1b5
Calltrace:
flush_old_commits +0x113/0x16f
reiserfs_write_super +0x98/0x9a
sync_supers +0xd0/0xea
do_sync
sys_sync
syscall_call

5.
syncing...(after mkfs so it was almost done)
Unable to handle kernel paging request at virtual address 9756a996
EIP is at cleanup_bitmap_list +0xb/0xd4
Calltrace:
autoremove_wake_function
cleanup_freed_for_journal_list
...

6.
attempted to kill init
bad: schedulling while atomic
EIP is at add_wait_queue

And much more (mostly in FS code)

Tested ciphers: aes, blowfish (both as module and compiled in)

Filesystems with crypto file: ReiserFS, FAT

Tested sizes of crypto file: 50MB, 10GB

Tested disk drives and controllers:
ICH5 with WD120JB (pata), external
CMD649 (Kouwell 671A) with 80GB Seagate barracuda IV

Tested chipsets:
I865 (Asus P4P800), I875 (Abit IC7 G)

Other hardware: P4 2.6 (HT, SMP kernel), 1GB RAM (High memory support 
4GB). Thoroughly tested with memtest and mprime95.

See lspci and config in attachment.

Kernel is not tainted.

Write me please if additional information is need.

miho

PS. Excuse my poor english.