Re: _text vs _start

[Hollis Blanchard <hollisb@us.ibm.com>]

On Wed, 2007-01-03 at 21:32 +0000, Keir Fraser wrote:
> On 3/1/07 9:22 pm, "Hollis Blanchard" <hollisb@us.ibm.com> wrote:
> 
> > On Wed, 2007-01-03 at 15:07 -0600, Hollis Blanchard wrote:
> >> Given that you do arithmetic with _end, can you explain why you're not
> >> using _start, which is a standard symbol provided by the default linker
> >> script?
> >
> > My mistake; _start of course isn't a linker script symbol at all, but
> > rather the entry point code.
> 
> There is an unnecessary disagreement among architectures over what symbols
> should be used to mark section and image boundaries. We could reasonably
> agree on at least _start/_end and _stext/_etext I think. This would allow
> functions like is_kernel_text() to become generic, and make it obvious which
> labels kexec should be using.

Sounds great to me.

PowerPC already arranges for _start to be at the very beginning
of .text, which is at the beginning of the first PT_LOAD segment... so
the end result is that the address of _start is the same as our link
address.

We also provide _etext, and _end, but not _stext (currently).

-- 
Hollis Blanchard
IBM Linux Technology Center