More USB-panics (umass)

I have just bought an USB Card-Reader/Writer.

Product name:
"hama - USB 2.0 Card Reader 9 in 1"

USB-info (kernel):
Apr  5 13:17:41 klotz kernel: ata0: at 0x1f0 irq 14 on atapci0
Apr  5 13:17:41 klotz kernel: ata1: at 0x170 irq 15 on atapci0
Apr  5 13:17:41 klotz kernel: uhci0: <Intel 82371AB/EB (PIIX4) USB
controller> port 0xc000-0xc01f irq 12 at device 7.2 on pci0
Apr  5 13:17:41 klotz kernel: uhci0: [GIANT-LOCKED]
Apr  5 13:17:41 klotz kernel: usb0: <Intel 82371AB/EB (PIIX4) USB
controller> on uhci0
Apr  5 13:17:41 klotz kernel: usb0: USB revision 1.0
Apr  5 13:17:41 klotz kernel: uhub0: Intel UHCI root hub, class 9/0, rev
1.00/1.00, addr 1
Apr  5 13:17:41 klotz kernel: uhub0: 2 ports with 2 removable, self
powered
Apr  5 13:17:41 klotz kernel: ums0: Logitech USB Receiver, rev
1.10/9.10, addr 2, iclass 3/1
Apr  5 13:17:41 klotz kernel: ums0: 5 buttons and Z dir.
Apr  5 13:17:41 klotz kernel: umass0: ICSI 2.0 Card Reader, rev
2.00/1.3a, addr 3
Apr  5 13:17:41 klotz kernel: da0 at umass-sim0 bus 0 target 0 lun 0
Apr  5 13:17:41 klotz kernel: da0: <ICSI CF Card       CF 1.3A>
Removable Direct
 Access SCSI-0 device 
Apr  5 13:17:41 klotz kernel: da0: 1.000MB/s transfers
Apr  5 13:17:41 klotz kernel: da0: 122MB (250368 512 byte sectors: 64H
32S/T 122
C)

(I will send a more complete listing, if requested.)

Problem:
Accessing the device freezes the active process
(e.g. mount, umount, newfs). Attaching and detaching
the card reader gives panic()s, which look like this:

panic type 1:
-------------
uhci_abort_xfer: not in process context at line 1941 in file
/usr/src/sys/dev/usb/uhci.c
.
.
.
ad0: TIMEOUT_WRITE_DMA retrying (2 retries left) LBA=xxxxx

panic type 2:
-------------
umass0: at hub0 port 2 (addr 3) disconnected
(da0: umass0-sim0:0:0:0): lost device
.
.
.
umass0: detached
panic: initiate_write_inodeblock_ufs2: already started
at line 3770 in file /usr/src/sys/ufs/ffs/ffs_softdep.c
synching disks, buffers remaining ... initiate_write_filepage:
already started
ad0: TIMEOUT_WRITE_DMA retrying (2 retries left) LBA=xxxxx

---

Further information:
I have checked the device with MS-Windows 2000 and I am pretty
sure that it's completely OK (no drivers needed, which usually means
that the device is USB-compliant). I have successfully written a file
on my Compactflash card with MS-Windows 2000 (msdosfs). When trying
to mount it as msdosfs, FreeBSD refused to do it. I could mount
it as UFS1 with softupdates, but later after getting the directory
listing, it panic()'ed.

>From this behavior I am sure that FreeBSD-CURRENT on my 2 boxes
never accessed the compactflash, because no data could be read
and no data could be written to it. I checked the data on the
compactflash on my MS-Windows 2000 box and nothing has been
destroyed (even after a successful(!) newfs).

I have a fresh CURRENT:
FreeBSD klotz.local 5.2-CURRENT FreeBSD 5.2-CURRENT #0: Sun Mar 28
22:10:17 CEST 2004     xxx_at_klotz.local:/usr/obj/usr/src/sys/KLOTZ  i386

My USB-mouse works well here.

---

If you need more infos, please send me an email. I would be glad, if
the USB-support on CURRENT was complete.

Martin