USB problem in linux 2.4.20

[ductusrhe]

Hi,
 
We have a problem with the usb-lowlevel and/or usb-storage components.
OS        Montavista Preview Linux 2.4.20
Processor PPC440EP
 
We use an USB disc-on-chip quite heavily to store data from many threads (about 17).
The problem is that sometimes all threads/apps that use the usb device hangs (forever) waiting for disc access, and the CPU load goes down to 0.

We have located the hanging to wait_for_completion() in command_abort() in scsiglue.c.
Since this is an error handling function, it might either be a bug in it, or that which caused the error to happen is the problem. The hanging happens every time the command_abort() is run.
Perhaps it's the scsi timeout of 30 sec, since so many threads are running...?

I wonder if someone have encountered this problem, solved it, found patches, or if someone knows of fixes that are currently in the 2.6 kernel for this processor that solves the problem.
 

Some files involved:
 
drivers/usb/usb-ocp-ohci.c 
drivers/usb/usb.c
drivers/usb/storage/scsiglue.c
drivers/usb/storage/scsi_error.c
 
 
/Ronnie Hedlund
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