Re: Ingo's realtime_preempt patch causes kernel oops

Sven-Thorsten Dietrich
2006-05-24T17:10:05Z

On Wed, 2006-05-24 at 18:55 +0200, Thomas Gleixner wrote:
> On Wed, 2006-05-24 at 12:38 -0400, Steven Rostedt wrote:
> > OK I haven't worked on arm much at all. Only had to port one board
> > before, and didn't need to get too involved.
> >
> > Can't two devices share the same interrupt line? Not talking about a
> > cascading interrupt controller, but two actual devices that can trigger
> > a single interrupt line. So, if this is the case, how do you disable a
> > particular source without going to the driver itself?
>
> Yeah, the demux code has to go into the device driver to figure that
> out, which is not hard to do on SoC devices, as the peripherals are
> usually unique for a given SoC family.
>
> PCI and other globally shared devices are completely differnt beasts and
> you would need a legion of hackers to fix that up.
>

I am looking at a particular case where I am dealing with it on PCI,
and sharing USB.

In this particular case, the uhci USB driver is almost structured,
such that we can execute the lockless portion, and then run the locked
code in a thread...

Sven

> tglx
>
>
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