USB flash regression between 9.0-BETA1 and r227413

[Ed Maste]

After rebuilding and installing a new kernel from a couple of weeks ago
my embedded USB flash no longer works.

Working kernel was:
FreeBSD 9.0-BETA1 #1 r225223M: Sat Aug 27 22:21:54 EDT 2011

Dec  1 16:40:14 edlaptop kernel: ugen3.2: <Micron Technology> at usbus3
Dec  1 16:40:14 edlaptop kernel: umass0: <Micron Technology Real SSD eUSB 16GB, class 0/0, rev 2.00/11.10, addr 2> on usbus3
Dec  1 16:40:14 edlaptop kernel: umass0:  SCSI over Bulk-Only; quirks = 0x0000
Dec  1 16:40:15 edlaptop kernel: umass0:2:0:-1: Attached to scbus2
Dec  1 16:40:19 edlaptop kernel: (probe0:umass-sim0:0:0:0): TEST UNIT READY. CDB: 0 0 0 0 0 0
Dec  1 16:40:19 edlaptop kernel: (probe0:umass-sim0:0:0:0): CAM status: SCSI Status Error
Dec  1 16:40:19 edlaptop kernel: (probe0:umass-sim0:0:0:0): SCSI status: Check Condition
Dec  1 16:40:19 edlaptop kernel: (probe0:umass-sim0:0:0:0): SCSI sense: UNIT ATTENTION asc:28,0 (Not ready to ready change, medium may have changed)
Dec  1 16:40:19 edlaptop kernel: da0 at umass-sim0 bus 0 scbus2 target 0 lun 0
Dec  1 16:40:19 edlaptop kernel: da0: <MICRON eUSB DISK 1110> Fixed Direct Access SCSI-0 device
Dec  1 16:40:19 edlaptop kernel: da0: 40.000MB/s transfers
Dec  1 16:40:19 edlaptop kernel: da0: 15488MB (31719424 512 byte sectors: 255H 63S/T 1974C)


Failing kernel is:
FreeBSD 9.10-CURRENT #3 r227413M: Fri Nov 11 01:18:34 EST 2011

It repeats attach / detach in a loop indefinitely:

Dec  1 20:52:57 edlaptop kernel: ugen3.3: <Micron Technology> at usbus3
Dec  1 20:52:57 edlaptop kernel: umass0: <Micron Technology Real SSD eUSB 16GB,
class 0/0, rev 2.00/11.10, addr 3> on usbus3
Dec  1 20:52:57 edlaptop kernel: umass0:  SCSI over Bulk-Only; quirks = 0x0100
Dec  1 20:52:57 edlaptop kernel: umass0:2:0:-1: Attached to scbus2
Dec  1 20:53:07 edlaptop kernel: ugen3.3: <Micron Technology> at usbus3 (disconnected)
Dec  1 20:53:07 edlaptop kernel: umass0: at uhub3, port 4, addr 3 (disconnected)
Quirks for this device was 0 in the working case, now quirks = 0x0100 in
the failing case.

-Ed