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Date: Mon, 5 May 2003 09:34:44 -0700
From: Richard Henderson <rth@twiddle.net>
To: David.Mosberger@acm.org
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] fix vsyscall unwind information
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On Mon, May 05, 2003 at 08:05:58AM -0700, David Mosberger-Tang wrote:
>   Richard> Why?  Certainly it isn't needed for x86.
> 
> Certain applications (such as debuggers) want to know.  Sure, you can
> do symbol matching (if you have the symbol table) or code-reading
> (assuming you know the exact sigreturn sequence), but having a marker
> would be more reliable and faster.

Eh.  The whole point was to *eliminate* the special cases.

If the debugger does nothing special now, it'll see the symbol
from the VDSO in the backtrace and print __kernel_sigreturn.
Isn't this sufficient for the user to recognize what's going on?
Does it really need to print <signal frame>?



r~