Re: [PATCH update] firewire: reread config ROM when device resetthe bus

From: Stefan Richter
Date: Wed Mar 05 2008 - 18:54:54 EST


I wrote:
I wrote:
- moved from dev->dem to idr_rwsem
- extended note about semaphore protection of .config_rom and
.config_rom_length
- secure a few more places which access the config_rom...
should have covered all of them now

Hmm. When I power the PC down there are lots of messages scrolling by
which look somewhat like lockdep spew. I can't reproduce this merely by
module unloading though. So don't put this patch into production yet.

/...a few hundreds reboots later.../

No, it is not this patch. It is something else. And whatever it is, it is already present in 2.6.25-rc3.

To reproduce it, I need to plug an SBP-2 device in and out, then shut the machine down (e.g. shutdown -h now, whereas shutdown -r now does not seem to trigger the bug).

Since it happens after all filesystems were unmounted or r/o-mounted, I can't capture the log output easily (perhaps with a netconsole or so) but it also can't do any damage at that point anymore.

It does not happen with ohci1394 + sbp2, so it is obviously located in the firewire stack.

I am now gradually removing debug options from the kernel to see which debug facility is making the fuzz...
--
Stefan Richter
-=====-==--- --== --=-=
http://arcgraph.de/sr/
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