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From: Nicholas Sherlock <n.sherlock@gmail.com>
Date: Tue, 24 Jan 2012 02:44:00 -0000
Message-ID: <CADwwazavZ-qwsG3Jm15ZL6-fx0r0JK41qWO9_YTEtOkztjsYnQ@mail.gmail.com>
Subject: Re: ARM EABI Linux, breakpoints cause SIGILL and target dies
To: Ulrich Weigand <uweigand@de.ibm.com>
Cc: gdb@sourceware.org
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On 24 January 2012 02:29, Ulrich Weigand <uweigand@de.ibm.com> wrote:
> If this does not work correctly for some reason, this would explain
> both why GDB doesn't recognize the situation *and* also why the
> kernel doesn't recognize the breakpoint instruction to convert the
> signal into a SIGTRAP.

Yeah, that sounds likely.

> Do you see any differences either here in traps.c, or in one of the
> entry-*.S assembler files, between your two kernels?

Thanks for the pointer! I found the commit that fixed this bug in the
ARM kernel entry routine:

https://github.com/cyanogen/cm-kernel-exp/commit/d12aee22b3e025a4b76d4078f76542ea8cbd0315#diff-0

I'll port that patch over to my kernel and see if it fixes GDB.

Cheers,
Nicholas Sherlock