Messages in this thread | | | Date | Thu, 2 Feb 2012 11:11:16 -0800 | From | "Paul E. McKenney" <> | Subject | Re: rcu warnings cause stack overflow |
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On Thu, Feb 02, 2012 at 03:52:20PM +0100, Frederic Weisbecker wrote: > On Thu, Feb 02, 2012 at 01:27:42PM +0100, Heiko Carstens wrote: > > On Wed, Feb 01, 2012 at 04:14:48PM +0100, Frederic Weisbecker wrote: > > > > Removing the WARN_ON_ONCE will fix this and, if lockdep is turned on, still > > > > will find illegal uses. But it won't work for lockdep off configs... > > > > So we probably want something better than the patch below. > > > > > > Ah ok. Hmm, but why are you using an exception to implement WARN_ON() > > > in s390? Is it to have a whole new stack for the warning path in order > > > to avoid stack overflow from the place that called the WARN_ON() ? > > > > The reason was to reduce the code footprint of the WARN_ON() and also > > be able to print the register contents at the time the warning happened. > > Ah ok, makes sense.
So Frederic should push his anti-recursion patch, then?
Thanx, Paul
> > All architectures which define __WARN_TAINT implement warnings with > > exceptions. Currently that are parisc, powerpc, s390 and sh. > > >
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