Message-ID: <1379969467.11249.21.camel@pasglop>
Subject: Re: [PATCH] powerpc/irq: Run softirqs off the top of the irq stack
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
        Peter Zijlstra <peterz@infradead.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>,
        Paul Mackerras <paulus@au1.ibm.com>, Ingo Molnar <mingo@kernel.org>,
        James Hogan <james.hogan@imgtec.com>,
        "James E.J. Bottomley" <jejb@parisc-linux.org>,
        Helge Deller <deller@gmx.de>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>,
        Heiko Carstens <heiko.carstens@de.ibm.com>,
        "David S. Miller" <davem@davemloft.net>,
        Andrew Morton <akpm@linux-foundation.org>
Date: Tue, 24 Sep 2013 06:51:07 +1000
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On Mon, 2013-09-23 at 09:47 -0700, Linus Torvalds wrote:
> On Sun, Sep 22, 2013 at 9:35 PM, Benjamin Herrenschmidt
> <benh@kernel.crashing.org> wrote:
> >
> > This is the "band aid" discussed so far for the stack overflow
> > problem for powerpc.
> 
> I don't think it's a "band-aid" in any way, except perhaps in the
> sense that there are certainly other things we can also do in this
> series (ie I liked Frederic's cleanups etc).

Ah yes, I thought of it as a band-aid in the sense that a better
approach would be to switch to the irq stack earlier like x86_64 does
but that would be a lot more invasive. Definitely something I would look
into if I was to tackle changing how we do per-cpu and the PACA though.

Cheers,
Ben.


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