On Fri, 2013-09-20 at 13:11 +0200, Peter Zijlstra wrote: > On Fri, Sep 20, 2013 at 01:03:17PM +0200, Thomas Gleixner wrote: > > On Thu, 19 Sep 2013, Linus Torvalds wrote: > > > > > On Thu, Sep 19, 2013 at 2:51 PM, Frederic Weisbecker <fweis...@gmail.com> > > > wrote: > > > > > > > > It fixes stacks overruns reported by Benjamin Herrenschmidt: > > > > http://lkml.kernel.org/r/1378330796.4321.50.camel%40pasglop > > > > > > So I don't really dislike this patch-series, but isn't "irq_exit()" > > > (which calls the new softirq_on_stack()) already running in the > > > context of the irq stack? And it's run at the very end of the irq > > > processing, so the irq stack should be empty too at that point. > > > > Right, but most of the implementations are braindamaged. > > > > irq_enter(); > > handle_irq_on_hardirq_stack(); > > irq_exit(); > > I was only just staring at i386 and found it did exactly that. It had to > jump through preempt_count hoops to make that work and obviously I > hadn't test-build the preempt patches on i386.
Right and powerpc does the switch even later when calling the individual handlers. Ben. > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
