On Wed, 2005-03-23 at 16:25 +0100, Jens Axboe wrote: > Let me guess, it is hanging in wait_for_completion()?
Yes, I have the trace now. Why is curious. This is the trace of the failure: Mar 24 18:40:34 localhost kernel: usb 4-2: USB disconnect, address 3 Mar 24 18:40:34 localhost kernel: sd 0:0:0:0: CMD c25c98b0 done, completing Mar 24 18:40:34 localhost kernel: 0:0:0:0: cmd c25c98b0 returning Mar 24 18:40:34 localhost kernel: 0:0:0:0: cmd c25c98b0 going out <6>Read Capacity (10) 25 00 00 00 00 00 00 00 00 00 Mar 24 18:40:34 localhost kernel: scsi0 (0:0): rejecting I/O to dead device (req c25c98b0) Mar 24 18:40:34 localhost kernel: usb 4-2: new full speed USB device using uhci_hcd and address 4 Mar 24 18:40:34 localhost kernel: scsi1 : SCSI emulation for USB Mass Storage devices Mar 24 18:40:34 localhost kernel: 1:0:0:0: cmd c1a1b4b0 going out <6>Inquiry 12 00 00 00 24 00 The problem occurs when the mid-layer rejects the I/O to the dead device. Here it returns BLKPREP_KILL to the prep function, but after that we never get a completion back. I'll dig around in ll_rw_blk.c to see if I can trace the problem, but you know this code better than I do ... James - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/