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From:   Matt Fleming <matt@console-pimps.org>
To:     Ralf Baechle <ralf@linux-mips.org>
Cc:     linux-mips@linux-mips.org, Adam Jiang <jiang.adam@gmail.com>
Subject: Re: How to detect STACKOVEFLOW on mips
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On Wed, 30 Jun 2010 15:50:06 +0100, Ralf Baechle <ralf@linux-mips.org> wrote:
> 
> There used to be some code for other architectures that zeros the stack
> page and counts how much of that has been overwritten by the stack.  That
> was never ported to MIPS.
> 
> Another helper to find functions that do excessive static allocations is
> "make checkstack".

Both SH and sparc use the mcount function (enabled with the -pg switch
to gcc) to check the stack has not overflowed. The relevant code is in
arch/{sh,sparc}/lib/mcount.S. This checks the stack pointer value on
every function call. Yeah, it's heavy-weight, but an implementation for
MIPS should be able to catch almost the exact point at which stack
overflow occurs.