Re: [PATCH 08/28] nios2: MMU Fault handling

[Geert Uytterhoeven <geert@linux-m68k.org>]

On Tue, Apr 22, 2014 at 4:30 PM, Ezequiel Garcia
<ezequiel.garcia@free-electrons.com> wrote:
> On Apr 18, Ley Foon Tan wrote:
>> +
>> +bad_area_nosemaphore:
>> +     /* User mode accesses just cause a SIGSEGV */
>> +     if (user_mode(regs)) {
>
> I found that it's useful to add some printing here, just as ARM
> does. I carry this patch on my kernel:
>
> +               printk(KERN_INFO "%s: unhandled page fault (%d) at 0x%08lx, cause %ld\n",
> +                      current->comm, SIGSEGV, address, cause);
> +               show_regs(regs);
>
> Do you think we could do something like it? Maybe with a compile time option?

Can this easily be triggered from userspace? If yes, please use
pr_info_ratelimited().

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds