Re: [PATCH] xtensa: improve stack dumping

[Max Filippov]

On Wed, Nov 6, 2019 at 12:51 PM Dmitry Safonov <dima@xxxxxxxxxx> wrote:
> On 11/6/19 6:16 PM, Max Filippov wrote:
> > @@ -512,10 +510,12 @@ void show_stack(struct task_struct *task, unsigned long *sp)
> >       for (i = 0; i < kstack_depth_to_print; i++) {
> >               if (kstack_end(sp))
> >                       break;
> > -             pr_cont(" %08lx", *sp++);
> > +             sprintf(buf + (i % 8) * 9, " %08lx", *sp++);
>
> buf is on the stack, does sprintf() put null-terminator for hex?

It should put null-terminator regardless of the format string.

> >               if (i % 8 == 7)
> > -                     pr_cont("\n");
> > +                     pr_info("%s\n", buf);
> >       }
> > +     if (i % 8)
> > +             pr_info("%s\n", buf);
>
> If the stack trace ends with (i % 8 == 7), you'll double-print the last
> line?

No, I don't think so. 'For' loop condition is checked after i++, so if
loop ends with i % 8 == 7 then its last iteration was done with
i % 8 == 6 and thus the buf haven't been printed.

-- 
Thanks.
-- Max