Re: [PATCH]: grub: Fix sparc64 setjmp implementation, update grub_setjmp() attributes.

["Yoshinori K. Okuji" <okuji@enbug.org>]

On Saturday 28 March 2009 22:39:48 Robert Millan wrote:
> On Wed, Mar 25, 2009 at 09:13:52PM -0700, David Miller wrote:
> > The FSF has received my copyright assignment paperwork so I'm starting
> > to feed fresh copies of my sparc64 changes.
> >
> > Here, we fix the setjmp assembler implementation for sparc64 and also
> > we fix all of the grub_setjmp declarations to have the proper
> > "returns_twice" attribute.
> >
> > For normal "setjmp" GCC recognizes this special function name and
> > internally adds the attribute.  Amongst other things this makes sure
> > GCC does not emit a tail-call in functions that call grub_setjmp().
> > Since we use a special name for setjmp in GRUB we need to explicitly
> > add the attribute.
> >
> > Without this fix, GCC on sparc64 really did emit a tail-call in the
> > nomal module where grub_setjmp() is called, and this led to myserious
> > crashes :-)
> >
> > 2009-03-25  David S. Miller  <davem@davemloft.net>
> >
> > 	* normal/sparc64/setjmp.S: Fix setjmp implementation.
> > 	* include/grub/sparc64/setjmp.h (grub_jmp_buf): Update.
> > 	(grub_setjmp): Mark with 'returns_twice' attribute.
> > 	* include/grub/i386/setjmp.h (grub_setjmp): Likewise
> > 	* include/grub/powerpc/setjmp.h (grub_setjmp): Likewise.
> > 	* include/grub/x86_64/setjmp.h (grub_setjmp): Likewise.
>
> Hi,
>
> Unless there's someone else in the list who is knowledgeable about sparc
> assembly and is going to review this part of David's patch, I'm going to
> assume it's fine and check it in.
>
> This also goes for future patches sent by David.  So if you will speak,
> do it now :-)

I know a bit, but not that much. So I vote for that we just trust him. ;)

Regards,
Okuji