On Wed, Oct 21, 2015 at 07:39:22AM -0400, Steven Rostedt wrote: > On Wed, 21 Oct 2015 10:01:42 +0200 > Peter Zijlstra <[email protected]> wrote: > > > > I should probably add a "if (in_nmi()) return" somewhere. > > > > But if there's an arch that doesn't use a separate NMI stack, the NMI > > might cause the largest stack, which would then remain invisible from > > the stack-tracer. > > > > Should we not instead fix the NMI-safety of this tracer? > > We could, but that should be a separate project, as that would require > doing everything lockless, which would require a redesign. Is that > worth it?
I've no idea on either, not on how hard it would be to fix, nor on if its worth the effort. I suppose auditing which archs do not have dedicated NMI stacks might be a good first stab at things. x86 still uses an IST for NMIs, right? Andy's been changing things a lot lately, I'm not sure I'm up to date on this. > For now, the safe thing to do is the if (in_nmi()), but certainly, if > someone gets time to make it NMI safe, we can do that too. Sure, fix current holes first. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
