On Tuesday 22 January 2002 14:09, Greg KH wrote: > On Tue, Jan 22, 2002 at 12:40:23PM -0500, David Johnson wrote: > > Hi, > > > > I am developing a device driver for a USB network adapter and am seeing > > occasional data corruption when sending data to or recieving data from > > the device. In particular this occurs under heavy traffic. > > > > Under Redhat 7.1 I occasionally lose the first 16 bytes of a packet of > > data that I send to the device. This appears to be fixed somewhere > > between Redhat 7.1 and kernel 2.4.17. Is/was this a known issue and does > > anyone know when this was fixed? > > Red Hat 7.1 shipped with 2.4.2 I think. That was almost a year ago, so > yes, lots of things have been fixed since then :)
Yes, I believe that. It would just be nice to know for sure that it is really a problem that was fixed and not one that just hasn't shown up yet under 2.4.17 since it is an occasional problem (although I can fairly consistantly reproduce it under RH7.1). I believe it also fails under the latest Mandrake version using kernel 2.4.8. If there was a work around we could implement then that would be nice too. This is going to be a retail product and if possible would like to say we support Redhat 7.1 out of the box (without requiring the user upgrade their kernel as that is an ugly solution). > > Under Redhat 7.1 and with the 2.4.17 kernel I occasionally see corrupted > > data being received from the device. The nature of the corruption is not > > consistent. Sometimes extra bytes are appended to the beginning of a > > packet, sometimes I get a packet with a few bytes that don't seem to come > > from anywhere in particular. Does anyone have any ideas what might cause > > this problem? > > Do you have any specifics? Can you compare the data received in your > urb with the data that went across the wire? Like I said, it appears that occasionally I will get a packet that will have mysterious bytes appended to the start of the packet. I haven't determined where the bytes are coming from but it is random. Sometimes it is a couple bytes, sometimes it is 8 or 9. Sometimes they aren't even appended to the front of a real packet. It only seems to happen under heavy traffic situations. > > I am using the usb-uhci driver. Any ideas? > > Does the same problem happen with the uhci or usb-ohci drivers? Does it > happen with other host controller chips? The uhci driver has more serious problems. My driver has never properly worked with uhci. I have never tested usb-ohci or other host controller chips as I don't have access to a system with non-uhci host controllers. David _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
