usb/150401: Errors from USB drives mixed between UFS and ZFS

[Decibel!]

>Number:         150401
>Category:       usb
>Synopsis:       Errors from USB drives mixed between UFS and ZFS
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-usb
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Sep 09 03:00:08 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Decibel!
>Release:        FreeBSD 8.1-RELEASE amd64
>Organization:
>Environment:
System: FreeBSD noel.decibel.org 8.1-RELEASE FreeBSD 8.1-RELEASE #0: Thu Sep 2 19:38:40 CDT 2010 root at noel.decibel.org:/usr/obj/usr/src/sys/GENERIC amd64


>Description:
I have a system with 3 USB drives: 2 are in a zpool mirror (though I've seen
the same behavior with them in a simple zpool stripe), one is stand-alone UFS.

I can hit either ZFS or the UFS drive hard (running bonnie++) and things are
fine. But as soon as I start hitting both of them, I start getting errors:

Sep  6 03:16:31 noel kernel: (da0:umass-sim0:0:0:0): AutoSense failed
Sep  6 03:16:31 noel root: ZFS: vdev I/O failure, zpool=zsb path=/dev/da0 offset=1145095418880 size=1024 error=5
(I'll get some number of the second error, usually between 5 and 20 per incident).

The frequency of these errors is dependent on workload. I've been rsyncing some
data at a rate of ~500kB/s (rsync --bwlimit=500) and that's generating roughly
3 events per hour:

Sep  6 00:36:00 noel kernel: (da1:umass-sim1:1:0:0): AutoSense failed
Sep  6 01:37:11 noel kernel: (da1:umass-sim1:1:0:0): AutoSense failed
Sep  6 01:38:25 noel kernel: (da1:umass-sim1:1:0:0): AutoSense failed
Sep  6 01:40:02 noel kernel: (da1:umass-sim1:1:0:0): AutoSense failed
Sep  6 01:41:03 noel kernel: (da1:umass-sim1:1:0:0): AutoSense failed
Sep  6 01:41:34 noel kernel: (da1:umass-sim1:1:0:0): AutoSense failed
Sep  6 02:18:27 noel kernel: (da0:umass-sim0:0:0:0): AutoSense failed
Sep  6 02:37:36 noel kernel: (da1:umass-sim1:1:0:0): AutoSense failed
Sep  6 02:42:30 noel kernel: (da1:umass-sim1:1:0:0): AutoSense failed
Sep  6 03:13:30 noel kernel: (da0:umass-sim0:0:0:0): AutoSense failed
Sep  6 03:15:38 noel kernel: (da1:umass-sim1:1:0:0): AutoSense failed
Sep  6 03:16:31 noel kernel: (da0:umass-sim0:0:0:0): AutoSense failed

The errors are always on the ZFS drives (da0, da1); I haven't seen any on the
UFS drive.

decibel at noel.2[22:32]~:15>sudo usbconfig
ugen0.1: <OHCI root HUB nVidia> at usbus0, cfg=0 md=HOST spd=FULL (12Mbps) pwr=ON
ugen1.1: <EHCI root HUB nVidia> at usbus1, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=ON
ugen1.2: <FreeAgent Seagate> at usbus1, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=ON
ugen1.3: <FreeAgent Seagate> at usbus1, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=ON
ugen1.4: <FreeAgent Pro Seagate> at usbus1, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=ON
ugen0.2: <USB Mouse Logitech> at usbus0, cfg=0 md=HOST spd=LOW (1.5Mbps) pwr=ON

>How-To-Repeat:
Hopefully someone else can repeat this with a similar setup.
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted: