Re: 3.14-mw regression: rtl8169 WARNING: DMA-API: exceeded 7 overlapping mappings of pfn 55ebe

[Eric Dumazet]

On Tue, 2014-02-11 at 18:07 -0800, Dan Williams wrote:

> The overlap granularity is too large.  Multiple dma_map_single
> mappings are allowed to a given page as long as they don't collide on
> the same cache line.
> 

I am not sure why you try number of mappings of a page.

Try launching 100 concurrent netperf -t TCP_SENFILE

Same page might be mapped more than 100 times, more than 10000 times in
some cases.




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