Hi, I found a problem *may* relate to the xhci driver. My laptop, HP Elitebook 8540w, has two USB 3.0 interfaces. After the laptop has been used for several days, the USB 3.0 interfaces does not work anymore; I can only use them to charge mobile devices. A restart will reset everything. Since the problem is reproducible, I found the following in my /var/log/messages: Sep 12 21:34:46 compaq kernel: ugen1.2: <SAMSUNG> at usbus1 (disconnected) Sep 12 21:34:46 compaq kernel: umass1: at uhub1, port 3, addr 1 (disconnected) Sep 12 21:34:46 compaq kernel: (da1:umass-sim1:1:0:0): lost device Sep 12 21:34:46 compaq kernel: (da1:umass-sim1:1:0:0): removing device entry Sep 12 21:34:54 compaq kernel: ugen1.2: <Unknown> at usbus1 (disconnected) And after that, ugen1.2 can no longer be recognized. ~> usbconfig ugen0.1: <EHCI root HUB Intel> at usbus0, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=SAVE ugen1.1: <XHCI root HUB 0x1033> at usbus1, cfg=0 md=HOST spd=SUPER (5.0Gbps) pwr=SAVE ugen2.1: <EHCI root HUB Intel> at usbus2, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=SAVE ugen0.2: <product 0x0020 vendor 0x8087> at usbus0, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=SAVE ugen2.2: <product 0x0020 vendor 0x8087> at usbus2, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=SAVE ugen0.3: <HP Integrated Module Broadcom Corp> at usbus0, cfg=0 md=HOST spd=FULL (12Mbps) pwr=ON ugen0.4: <product 0x0007 vendor 0x138a> at usbus0, cfg=0 md=HOST spd=FULL (12Mbps) pwr=ON ugen2.3: <product 0xce12 FV-U35> at usbus2, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=ON ugen2.4: <Mass Storage Device Prolific Technology Inc.> at usbus2, cfg=0 md=HOST spd=HIGH (480Mbps) pwr=ON It just disappeared. ugen1.1 should be another USB 3.0 interface, but after one of them is down, none of them works, and message ugen1.2: <Unknown> at usbus1 (disconnected) just keep shown when I plug/unplug USB devices. My FreeBSD is FreeBSD compaq.yuetime 8.2-STABLE FreeBSD 8.2-STABLE #8 r225370: Sun Sep 4 05:14:37 CDT 2011 lichray@compaq.yuetime:/usr/obj/home/lichray/devel/freebsd-stable/sys/HOUKAGO amd64 ____________ This may be a hardware problem btw, since I only used FreeBSD on this laptop, so I can't say whether other USB stacks work correctly. And in the most cases I plug in my Samsung Exhibit 4G. As you known, after an Android device has been plugged in, you need to select "Connect to USB" manually, which generates: Sep 7 15:04:12 compaq kernel: ugen1.2: <SAMSUNG> at usbus1 Sep 7 15:04:12 compaq kernel: umass1: <Mass Storage> on usbus1 Sep 7 15:04:14 compaq kernel: (probe0:umass-sim1:1:0:0): TEST UNIT READY. CDB: 0 0 0 0 0 0 Sep 7 15:04:14 compaq kernel: (probe0:umass-sim1:1:0:0): CAM status: SCSI Status Error Sep 7 15:04:14 compaq kernel: (probe0:umass-sim1:1:0:0): SCSI status: Check Condition Sep 7 15:04:14 compaq kernel: (probe0:umass-sim1:1:0:0): SCSI sense: UNIT ATTENTION asc:29,0 (Power on, reset, or bus device reset occurred) Sep 7 15:04:14 compaq kernel: (probe0:umass-sim1:1:0:0): TEST UNIT READY. CDB: 0 0 0 0 0 0 Sep 7 15:04:14 compaq kernel: (probe0:umass-sim1:1:0:0): CAM status: SCSI Status Error Sep 7 15:04:14 compaq kernel: (probe0:umass-sim1:1:0:0): SCSI status: Check Condition Sep 7 15:04:14 compaq kernel: (probe0:umass-sim1:1:0:0): SCSI sense: NOT READY asc:3a,0 (Medium not present) Sep 7 15:04:14 compaq kernel: da1 at umass-sim1 bus 1 scbus6 target 0 lun 0 Sep 7 15:04:14 compaq kernel: da1: <Android SGH-T759 0001> Removable Direct Access SCSI-2 device Sep 7 15:04:14 compaq kernel: da1: 40.000MB/s transfers Sep 7 15:04:14 compaq kernel: da1: Attempt to query device size failed: NOT READY, Medium not present for each time. (Btw, I hope gpart/devfs can detect the medium availability change on USB :) This makes the device not that "regular". So the problem may also caused by the device. -- Zhihao Yuan, nickname lichray The best way to predict the future is to invent it. ___________________________________________________ 4BSD -- http://4bsd.biz/