Re: [PATCH V2 2/3] dmaselftest: add memcpy selftest support functions

From: Vinod Koul
Date: Tue Nov 03 2015 - 11:07:45 EST


On Tue, Nov 03, 2015 at 08:31:57AM -0600, Timur Tabi wrote:
> Sinan Kaya wrote:
> >
> >Almost all DMA engine drivers come with some sort of selftest code
> >called from probe. I followed the same design pattern.
>
> As others have said, it appears that's outdated.
>
> Is there a real possibility that the hardware could fail the test
> without trashing the system? It seems that if the DMA engine is
> faulty, it won't "politely" fail. The whole system will crash or
> some memory will get corrupted and you won't know it.

Failing politely would be right thing to do. If DMA starts sending data to
anywhere in system memory due to bug or wrong addresses we can't do
anything to prevent that

--
~Vinod
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