Hi,

I'm using an external usb<->ide disk adapter to store my data. It is
identified as follow:

 umass0 at uhub1 port 1 configuration 1 interface 0
 umass0: Cypress Semiconductor USB2.0 Storage Device, rev 2.00/0.01, addr 2
 umass0: using SCSI over Bulk-Only
 scsibus0 at umass0: 2 targets, 1 lun per target
 sd0 at scsibus0 target 0 lun 0: <ST320082, 2A, 0000> disk fixed
 sd0: 186 GB, 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 390721968 sectors

It contains a single ffs (ufs2) partition. After some time using it, it
generate I/O error, the following message appears in /var/log/messages:

 umass0: BBB reset failed, STALLED
 umass0: BBB bulk-in clear stall failed, STALLED
 umass0: BBB bulk-out clear stall failed, STALLED

Google has some mention of this problem, which seems to be related to
crappy chips which does not like USB1 and uhci. The strange thing (maybe
not related at all to this problem) is that I worked for hours having it
mounted read-write without any kind of problem, and when I switched bask
to read-only, it generated errors after a few minute. 

Have you any hints/ideas/comments about this ?

regards,

 - Arnaud

ps: I forgot to mention that this machine is running -current fernel
from last week.