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To: Gavin Shan <gwshan@linux.vnet.ibm.com>, linuxppc-dev@lists.ozlabs.org
From: Michael Ellerman <mpe@ellerman.id.au>
Subject: Re: powerpc/powernv: Don't alloc IRQ map if necessary
Message-Id: <20150122055459.A5B3C140281@ozlabs.org>
Date: Thu, 22 Jan 2015 16:54:59 +1100 (AEDT)
Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>
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On Thu, 2015-08-01 at 05:42:32 UTC, Gavin Shan wrote:
> On PowerNV platform, the OPAL interrupts are exported by firmware
> through device-node property (/ibm,opal::opal-interrupts). Under
> some extreme circumstances (e.g. simulator), we don't have this
> property found from the device tree. For that case, we shouldn't
> allocate the interrupt map. Otherwise, slab complains allocating
> zero sized memory chunk.
 
That sounds fine. But the implementation is a bit messy.

Can you do a precursor patch which moves the logic into opal_irq_init(), that
way when you find no interrupts you can just return.

cheers