On Wed, 31 Aug 2005, MAL wrote: > Hi all, > > I have been using Linux with USB 2 for ~3 years, mostly as a means of > imaging hard disks (reading and writing via usb-storage and sd-mod), but > also to run ATAPI CD/DVD writers. I have had no problem with the latter > (apart from throughput speed), but the former has given me no end of grief. > > I've put off reporting this because every time I ask about it, I've been > told that USB2 development is still young in Linux and that the drivers > are not fully developed yet. USB2 is now old, so I've given up waiting, > here's the problem: > > I've tried an array of different USB to ATA adapters on an array of > different motherboards under an array of different kernels (2.4 & 2.6) > and I've tried toggling the USB2 features in 2.6 (iso transactions, > transaction translators). > Pretty much every time, I have a fully working device for a while > (reasonable speed transfers), and then I will get a tonne of SCSI read > (or write) errors (not an issue with the disk), followed by a SCSI reset > of the device which never recovers. I have to power off/disconnect the > device, which results in a segfault in the ehci-hcd driver, after which > my USB stack is screwed (the module won't even unload), and the system > needs a power cycle. > > Before I get the details and post them here, I wanted to make sure this > isn't a common problem and that I wouldn't be flogging a dead horse by > posting a load more error logs. > > Is USB 2 known to be stable in Linux on a large portion of host > controller hardware?
Some people have had problems, but most people seem to do okay. In general the problems are not the result of poor support in Linux for USB 2.0 but poor support in the devices. Before you start posting all sorts of debugging information and error logs, try using the recently-released 2.6.13 kernel. It includes a change to the error-recovery procedure in the usb-storage driver, which now will work more or less the same as error-recovery in Windows. Alan Stern ------------------------------------------------------- SF.Net email is Sponsored by the Better Software Conference & EXPO September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
