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Subject: Re: [PATCH] powerpc/xive: fix the fuzz value in xive_pick_irq_target()
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Michael Ellerman <mpe@ellerman.id.au>, =?ISO-8859-1?Q?C=E9dric?= Le
 Goater <clg@kaod.org>, linuxppc-dev@lists.ozlabs.org
Cc: Paul Mackerras <paulus@samba.org>, Nicholas Piggin <npiggin@gmail.com>
Date: Thu, 03 Aug 2017 10:58:48 +1000
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On Thu, 2017-08-03 at 10:01 +1000, Michael Ellerman wrote:
> Benjamin Herrenschmidt <benh@kernel.crashing.org> writes:
> 
> > On Wed, 2017-08-02 at 18:43 +0200, Cédric Le Goater wrote:
> > > If xive_find_target_in_mask() fails to find a cpu, the fuzz value used
> > > in xive_pick_irq_target() is decremented and reused in the last
> > > returning call to xive_find_target_in_mask(). This can result in such
> > > WARNINGs if the initial fuzz value is zero :
> > 
> > Ah indeed ... would have worked better if "fuzz" had been unsigned.
> 
> Is that an ack or a changes requested?

Either ;-) The original code would have been fine with an unsigned, I
didn't realize it was signed and going negative. That said, cedric
patch is fine.

Cheers,
Ben.