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

From: Geert Uytterhoeven
Date: Thu Apr 24 2014 - 03:18:32 EST


On Tue, Apr 22, 2014 at 4:30 PM, Ezequiel Garcia
<ezequiel.garcia@xxxxxxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxx

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
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