usb panics, ithread lockups, and atapi dma problems

[Andrew Atrens <atrens@xxxxxxxxxxxxxxxxxx>]

Hi All,

I'm seeing a variety of usb problems when using my Kingston Data Traveller
flash memory stick. And am also seeing atapi/dma problems as well.  

Here's a summary, I'm looking for a bit of advice as to how to proceed


When my memory stick is plugged in at boot time I get a panic. So far on 3/5
attempts. This looks like a bug Ian Dowse fixed in -stable back in
September, and related to the usb stack creating a kernel thread whenever a
device gets attached. If the device is attached during probing the fork1()
call runs calling splhigh() and then spl0(). The spl0() call was the
problem as this enables all interrupts - not a good idea to do during
device probing. Since the panic looked the same, I am blindly applying the
below patch in hope it will fix it.


Index: kern_fork.c
===================================================================
RCS file: /usr/dfly/repo/src/sys/kern/kern_fork.c,v
retrieving revision 1.17
retrieving revision 1.17.2.1
diff -b -B -r1.17 -r1.17.2.1
611a612
>     int s;
619c620
<       (void) splhigh();
---
>       s = splhigh();
622c623
<       (void) spl0();
---
>       splx(s);


may or may not be applicable to df, but not sure if the original spl0() was
100% correct to begin with. :|


The second problem I'm seeing is related to heavy device i/o on my data
stick. When I attempt to copy large files to or from my data stick, the
copy starts to work but about 5 seconds into it I get a complete lockup.

When I break to ddb and do a ps it tells me that I'm busy executing ithread1 
when I ask ddb to panic I get a synching filesystems message and it hangs
forever (well, forever in this case is at least 10 minutes).



The third problem I'm seeing is related to ata/dma and my cd burner.

For the longest time in -stable I'd been using 

hw.ata_atapi_dma=1  in my /boot/loader.conf file.

This doesn't work in DF. The probe finds my cd devices, but accessing them
always fails. Further, when I do an atacontrol reinit the devices just
disappear.

With hw.ata.atapi_dma=0  this doesn't happen.

been working fine in -stable with this same hw for over 6 months :(


Let me know how you'd like me to proceed.


Cheers,

Andrew.