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Date: Sat, 28 Sep 2002 20:26:56 +0200 (MET DST)
From: "Maciej W. Rozycki" <macro@ds2.pg.gda.pl>
To: davidm@hpl.hp.com
cc: mingo@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: show_stack()/show_trace() prototypes
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Organization: Technical University of Gdansk
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On Sat, 28 Sep 2002, David Mosberger wrote:

> Ingo, the ksymoops patch adds these to linux/sched.h:
> 
> extern void show_trace(unsigned long *stack);
> extern void show_stack(unsigned long *stack);
> 
> This is not good.  In general, it is not possible to do a reliable
> backtrace with just a stack pointer as a starting point (it is
> necessary to have access to the entire "preserved" machine state
> instead).  I'd suggest to either change the argument to a task_struct
> pointer (and update half a dozen platforms or so accordingly), or to
> leave the declarations platform-specific like they were before.

 Also the prototypes may differ, e.g. for MIPS/MIPS64 we have:

extern void show_trace(long *stack);

since MIPS addresses are signed and then, for consistency, we have:

extern void show_stack(long *stack);

as well.

-- 
+  Maciej W. Rozycki, Technical University of Gdansk, Poland   +
+--------------------------------------------------------------+
+        e-mail: macro@ds2.pg.gda.pl, PGP key available        +