Re: [PATCH] asm-generic: dma: Add BUG_ON for uninitialized dma_ops

From: Geert Uytterhoeven
Date: Wed Jan 20 2010 - 06:00:37 EST

On Wed, Jan 20, 2010 at 11:48, Alexey Dobriyan <adobriyan@xxxxxxxxx> wrote:
> On Wed, Jan 20, 2010 at 12:08 PM, Â<monstr@xxxxxxxxx> wrote:
>> From: Michal Simek <monstr@xxxxxxxxx>
>> Check that dma_ops are initialized correctly. Without this
>> checking you get kernel fault and you don't know where the problem is.
> Oh, yes you do. PC will be of some small value.

And the backtrace will tell you where to look...

>> + Â Â Â BUG_ON(!ops);
>> Â Â Â ÂBUG_ON(!valid_dma_direction(dir));
>> Â Â Â Âaddr = ops->map_page(dev, virt_to_page(ptr),



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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