On Wed, 30 Mar 2005, Steve McIntyre wrote: > I've just bought a Netac OnlyDisk U220 to replace an older flash key > that died. It behaves rather oddly. The device registers very slowly, > and then is _incredibly_ slow at doing bulk transfers (e.g. when > reading/writing). It works fine under Windows 2000. > > As an example: > > tack:/home/steve# dd if=/dev/zero of=/dev/sda > 81+0 records in > 80+0 records out > 40960 bytes transferred in 416.846622 seconds (98 bytes/sec) > > I hit Ctrl-C at this point... > > I've tracked down the cause of the problem; with debug enabled in > usb_storage I can see lots of "Bulk logical error" complaints from > usb_stor_Bulk_transport(). Further debugging tells me that the device > is sending broken signatures. The code checks for signatures of > > 0x53425355 (US_BULK_CS_SIGN) > 0x55425355 (US_BULK_CS_OLYMPUS_SIGN) > > but the output from this silly key is not matching those. It looks to > be _trying_ to return US_BULK_CS_SIGN, but I'm seeing variations in > byte 2: > > ... > Mar 30 15:49:21 tack kernel: usb-storage: Bulk Status S 0x53425355 T 0x5957 R > 0 Stat 0x0 > Mar 30 15:49:21 tack kernel: usb-storage: Bulk Status S 0x53425355 T 0x5958 R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x53425355 T 0x5959 R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x539e5355 T 0x595a R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x53425355 T 0x595b R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x531e5355 T 0x595c R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x53425355 T 0x595d R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x53bb5355 T 0x595e R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x53425355 T 0x595f R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x53845355 T 0x5960 R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x53fb5355 T 0x5961 R > 0 Stat 0x0 > Mar 30 15:49:22 tack kernel: usb-storage: Bulk Status S 0x53425355 T 0x5962 R > 0 Stat 0x0 > ... > > I can only assume that Windows is ignoring the signature altogether, > or has special-case coding for some devices. If this is a common error > in these devices, I'm amazed that nobody has complained about it > before. As it works under Windows, sending it back for a refund will > be difficult (of course). > > For now, I've simply commented out the signature check and I can now > use this key just fine. I've done data comparisons and it appears so > far that traffic is not corrupted. Would anyone be interested in a > patch to add an UNUSUAL_DEV flag and entry to work around this > breakage?
I've heard that Windows ignores the signature. Your experience seems to confirm this. We've seen devices that used their own special signatures instead of the standard one. But this is the first time I've seen a report of a device that randomly scrambles the signature! Maybe you can exchange the device for a different brand; that might be easier than trying to get a refund. Alan Stern ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ Linux-usb-users@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
