Re: [patch 4/8] Immediate Value - i386 Optimization; kprobes

[Andi Kleen <ak@suse.de>]

On Monday 18 June 2007 20:56:32 Andrew Morton wrote:
> On Mon, 18 Jun 2007 14:44:57 -0400
> Chuck Ebbert <cebbert@redhat.com> wrote:
> 
> > > I fancy it's done by the kprobe_page_fault handler, but I do not see
> > > clearly how writing the breakpoint from arch_arm_kprobe() in
> > > non-writeable memory is done.
> > 
> > Looks like it's not merged yet:
> > 
> > http://lkml.org/lkml/2007/6/7/2
> > 
> > This needs to go in before 2.6.22-final
> 
> Andi, I'll include the below two patches in the next batch, OK?

It won't work reliably unless some of the c_p_a() fixes get in first.

> 
> 
> 
> +extern int kernel_text_is_ro;

No externs in .c files


I also don't like kernel_text_is_read_only() much, it would
be better to just lookup_address() it and check the write flag.

But for 2.6.22 as a quick fix it might be better to just
make KPROBES dependent on !DEBUG_RODATA. That would be a one liner.

-Andi