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Date: Fri, 13 May 2016 09:16:47 +0200
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Subject: Re: [PATCH v7 45/50] drivers/of: Avoid recursively calling
 unflatten_dt_node()
From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Rob Herring <robherring2@gmail.com>
Cc: Gavin Shan <gwshan@linux.vnet.ibm.com>,
 linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
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 Bjorn Helgaas <bhelgaas@google.com>, Grant Likely <grant.likely@linaro.org>,
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On Wed, Nov 4, 2015 at 5:07 PM, Rob Herring <robherring2@gmail.com> wrote:
> On Wed, Nov 4, 2015 at 7:12 AM, Gavin Shan <gwshan@linux.vnet.ibm.com> wrote:
>> In current implementation, unflatten_dt_node() is called recursively
>> to unflatten device nodes in FDT blob. It's stress to limited stack
>> capacity.
>
> Did you actually hit a problem?
>
> Now we have a max depth of 64. Seems like that should be plenty... Any
> idea how this compares to when we run out of stack space?

FWIW, on arm64:

drivers/of/fdt.c:443:1: warning: the frame size of 1136 bytes is
larger than 1024 bytes [-Wframe-larger-than=]

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds