Re: [PATCH -rt DO NOT APPLY] Fix for tg3 networking lockup

From: Daniel Walker
Date: Thu Aug 03 2006 - 20:00:54 EST


On Thu, 2006-08-03 at 16:56 -0700, David Miller wrote:
> From: Theodore Tso <tytso@xxxxxxx>
> Date: Thu, 3 Aug 2006 19:53:26 -0400
>
> > Any suggestions on how I could figure out what was really going on and
> > what would be a better fix would be greatly appreciated.
>
> As Michael explained, it's the ASF heartbeat sent by tg3_timer() that
> must be delivered to the chip within certain timing constraints.
>
> If you had any watchdog devices on this machine, they would likely
> trigger too and reset your machine :)

That's not broken behavior in RT .. That's just plain old task
priorities. Some high priority task (SCHED_FIFO prio 99) is sucking up a
lot of the CPU. But that's 100% legal in SCHED_FIFO.

Daniel

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/