On Thu, Jul 21, 2016 at 02:56:52PM -0700, Andy Lutomirski wrote: > On Thu, Jul 21, 2016 at 2:21 PM, Josh Poimboeuf <jpoim...@redhat.com> wrote: > > When calling show_stack_log_lvl() or dump_trace() with a regs argument, > > providing a stack pointer or frame pointer is redundant. > > > > > diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c > > index 358fe1c..c533b8b 100644 > > --- a/arch/x86/kernel/dumpstack_32.c > > +++ b/arch/x86/kernel/dumpstack_32.c > > @@ -122,7 +122,7 @@ void show_regs(struct pt_regs *regs) > > u8 *ip; > > > > pr_emerg("Stack:\n"); > > - show_stack_log_lvl(NULL, regs, ®s->sp, 0, KERN_EMERG); > > + show_stack_log_lvl(NULL, regs, NULL, 0, KERN_EMERG); > > This is weird -- note the &. You're at some risk of exposing a bug in > x86_32's kernel_stack_pointer() function, which is a mess. (I don't > see why it's written the way it is -- the actual return stack pointer > given a pt_regs is quite well defined -- if regs->cs & 3 != 0, then > it's regs->sp, else it's ®s->sp.) > > That being said, this isn't a big deal, so: > > Reviewed-by: Andy Lutomirski <l...@kernel.org> > > If you want to make this all a bit more reliably on x86_32, you could > fix kernel_stack_pointer().
Ok. The whole '®s->sp' thing threw me for a loop. I have no idea what kernel_stack_pointer() is trying to do. I just assumed it was correct. I'll take a look at it and try to fix it in another patch. -- Josh