On Tue, 16 Apr 2019, Vlastimil Babka wrote: > On 4/16/2019 8:50 PM, Thomas Gleixner wrote: > > On Tue, 16 Apr 2019, Vlastimil Babka wrote: > > > >> On 4/16/19 4:22 PM, Qian Cai wrote: > >>> store_stackinfo() does not seem used in actual SLAB debugging. > >>> Potentially, it could be added to check_poison_obj() to provide more > >>> information, but this seems like an overkill due to the declining > >>> popularity of the SLAB, so just remove it instead. > >>> > >>> Signed-off-by: Qian Cai <cai@xxxxxx> > >> > >> I've acked Thomas' version already which was narrower, but no objection > >> to remove more stuff on top of that. Linus (and I later in another > >> thread) already pointed out /proc/slab_allocators. It only takes a look > >> at add_caller() there to not regret removing that one. > > > > The issue why I was looking at this was a krobot complaint about the kernel > > crashing in that stack store function with my stackguard series applied. It > > was broken before the stackguard pages already, it just went unnoticed. > > > > As you explained, nobody is caring about DEBUG_SLAB + DEBUG_PAGEALLOC > > anyway, so I'm happy to not care about krobot tripping over it either. > > > > So we have 3 options: > > > > 1) I ignore it and merge the stack guard series w/o it > > > > 2) I can carry the minimal fix or Qian's version in the stackguard > > branch > > > > 3) We ship that minimal fix to Linus right now and then everyone can > > base their stuff on top independently. > > I think #3 is overkill for something that was broken for who knows how long and > nobody noticed. I'd go with 2) and perhaps Qian's version as nobody AFAIK uses > the caller+cpu as well as the stack trace. > > For Qian's version also: > Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Ok. I'll pick it up and base the stackguard stuff on top. Thanks, tglx
