[openib-general] Re: [PATCH] SRP: don't use TX IU after freeing it

[Grant Grundler]

On Fri, Sep 30, 2005 at 01:38:05PM -0700, Roland Dreier wrote:
>     Grant> Christoph is right. Even if the code works, it's risky to
>     Grant> muck with the dma_addr_t contents. I'll try to look at this
>     Grant> tomorrow and if I have a better idea, propose it.  (I'm
>     Grant> pessimistic that I'll have a better idea though)
> 
> I don't think I buy this.  The DMA mapping API is giving us a
> gather/scatter list where each entry is a dma address X and a length
> Y.  The only manipulation we're doing is feeding this to the hardware
> as a list of chunks at addresses X, X + PAGE_SIZE, X + 2 * PAGE_SIZE,
> on up to whatever is required to cover the length Y.  This is exactly
> what any bus master would do when performing DMA, so I don't see how
> it is incorrect.

Yeah, you are right. I'm being too paranoid and didn't think about
how a bus master operates.

thanks,
grant