Hello Mr Gilliam;
Firstly thank you very much for your patch about single
stepping problem
on atomic instructions. In my opinion, this bug is very
critical for
powerpc arch (especially while kernel debugging). We have
experienced this
problem with both with h/w probe (BDI2000) and KGDB while
debugging
kernel. I have applied your patch to latest gdb (20060911
taken from cvs)
and after correctting some fail warnings and test it on a
PPC8540. It can
successfullt detects 'lwarx' instruction but can't step
over the loop and
a little moment later, it gives an error message like
'breakpoint.c:7730:
internal-error: remove_single_step_breakpoints: Assertion
`single_step_breakpoints[0] != NULL' failed.'
I have corrected some patch error, I dont know, maybe this
is the reason
of the problem. Here is the output of gdb and my test
program that include
atomic_dec function.
Where can be the problem? And thank alot again, because
atomic functions
are everywhere on kernel waiting to cause infinite loops..
Regards.
Emre KARA
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