Re: [PATCH 1/4] dump: Set dump info function pointers to NULL

[Janosch Frank]

On 11/8/23 09:03, Marc-André Lureau wrote:
> Hi
>
> On Tue, Nov 7, 2023 at 6:22 PM Janosch Frank <frankja@linux.ibm.com> wrote:
> > Better to not rely on the struct zeroing since NULL is not necessarily
> > 0.
> >
> > Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> > ---
> >   dump/dump.c | 3 +++
> >   1 file changed, 3 insertions(+)
> >
> > diff --git a/dump/dump.c b/dump/dump.c
> > index d355ada62e..1d38274925 100644
> > --- a/dump/dump.c
> > +++ b/dump/dump.c
> > @@ -1706,6 +1706,9 @@ static void dump_state_prepare(DumpState *s)
> >   {
> >       /* zero the struct, setting status to active */
> >       *s = (DumpState) { .status = DUMP_STATUS_ACTIVE };
> > +    s->dump_info.arch_sections_add_fn = NULL;
> > +    s->dump_info.arch_sections_write_hdr_fn = NULL;
> > +    s->dump_info.arch_sections_write_fn = NULL;
> >   }
>
> I think we would be in trouble if NULL is not 0. Do you have a better argument?

I'm one of those people who likes to distinguish between pointers and 
non-pointers but I have no problem dropping this.


OT: On s390 0x0 is a valid address but the kernel maps & handles it in a 
way that it will result in a null pointer if read/written to.