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SubjectRe: MAX_DMA_ADDRESS, virt_to_bus (and 3c505.c bug)
On Fri, 6 Nov 1998, Alan Cox wrote:

> (skb->data+skb->len)
>
> and you ought to check it doesnt span a page. The 85230 driver has the
> right bits in for that now. I've never seen a frame spanning a 64K boundary
> on x86, and the mm may actually mean it cant occur.

As all allocations start from a get_free_page, which only returns chunks
on their natural boundries (ie 4K on 4K boundry... 64K on 64K boundry).
Given that, unless the slab will allocate order > 4 chunks to satisfy
packet allocations... and it will. Oh well. At least you can be
reasonably sure that the packet won't cross the 16MB barrier.
-ben



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