Re: [Intel IOMMU 06/10] Avoid memory allocation failures in dma mapapi calls

[Arjan van de Ven]

Peter Zijlstra wrote:
> So a reclaim context (kswapd and direct reclaim) set PF_MEMALLOC to
> ensure they themselves will not block on a memory allocation. And it is
> understood that these code paths have a bounded memory footprint.


that's a too simplistic view though; what happens is that kswapd will 
queue the IO, but the irq context will then take the IO from the queue 
and do the DMA mapping... which needs the memory.....
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/