Re: Generic DMA - BUG_ON

From: Joerg Roedel
Date: Wed Jan 20 2010 - 06:00:57 EST


On Wed, Jan 20, 2010 at 10:53:50AM +0000, Russell King wrote:
> and ops is NULL, then this code will oops; you will get a full register
> dump and backtrace. You can use this information along with markup_oops.pl
> to find out where the problem is.

You can't rely on the oops if the code runs in process context. The
process may have address 0 mapped which would result in a security hole.
We had two of these bugs last year.

But I don't see any point in checking for dma_ops != NULL too. Any
developer would mention such a bug long before init is started.

Joerg


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