Re: [SCM] GNU Mach branch, master, updated. fe26ae2e9cb01a7507c7a929cc5555c7f6c1edfd

[Samuel Thibault]

Thomas Schwinge, le Tue 06 Sep 2011 01:56:59 +0200, a écrit :
> On Thu, 01 Sep 2011 01:02:26 +0000, Samuel Thibault 
> <samuel.thibault@ens-lyon.org> wrote:
> > commit 47a835d22b1a608fac5ee241474f128f64cb6a0f
> > Author: Samuel Thibault <samuel.thibault@ens-lyon.org>
> > Date:   Thu Sep 1 03:00:26 2011 +0200
> > 
> >     Close kernel stacks.
> >     
> >     * i386/i386/pcb.c (stack_attach): Initialize ebp to 0.
> 
> Is this another frame pointer than the one that is cleaned every time in
> i386/i386/cswitch.S:Thread_continue?

Mmm, good question.  I hadn't seen that ebp was cleared there.  The odd
thing is that I did get a case where the backtrace was not bound by
the 0 value, and it was apparently solved by initializing the value in
stack_attach along the esp initialization, which to me was making more
sense than setting it in some assembly code.

> (If yes, can we drop the assembly, or does it have another purpose?)

Thread_continue is only used in stack_attach, so it must be redundant
now.

Samuel