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Subject: Re: [rfa] Use a different breakpoint instruction for EABI GNU/Linux
From: Richard Earnshaw <rearnsha@gcc.gnu.org>
To: Daniel Jacobowitz <drow@false.org>
Cc: gdb-patches@sourceware.org
In-Reply-To: <20051111220241.GA30323@nevyn.them.org>
References: <20051111220241.GA30323@nevyn.them.org>
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Date: Sun, 13 Nov 2005 17:49:00 -0000
X-SW-Source: 2005-11/txt/msg00160.txt.bz2

On Fri, 2005-11-11 at 22:02, Daniel Jacobowitz wrote:
> Patches have been posted recently for the Linux kernel to use a different
> interface for system calls, in which r7 holds the syscall number instead of
> embedding it in the SWI.  With old-ABI compatibility mode disabled, the
> kernel never looks in the SWI at all.  Which means that using a SWI
> to set a breakpoint doesn't work very well.
> 
> Since 2003 the kernel has supported these particular undefined instructions
> (in the reserved space) as breakpoints.  So if we see an EABI binary, assume
> we have a recent vintage of kernel, and use them.
> 
> Tested on arm-none-linux-gnueabi.  OK for HEAD and 6.4?

OK.
R.