Messages in this thread | | | Date | Thu, 30 May 2002 03:54:07 -0700 (PDT) | Subject | Re: Does pci_alloc_consisent really need to zero memory? | From | "David S. Miller" <> |
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From: Emmanuel Michon <emmanuel_michon@realmagic.fr> Date: 30 May 2002 13:05:26 +0200
"David S. Miller" <davem@redhat.com> writes:
> I'd rather see a patch to DMA-mapping.txt that specifies the memory > returned is zeroed out, as this is what every implementation appears > to do. What was the idea when writing the code that zeroes memory? It seems so useless. Because 9 out of 10 drivers where I had to change virt_to_bus into the portable pci_alloc_consistent were using get_free_pages() which zeros things out for you.
I do actually remember that many of those instances in fact did depend on the memory being zero'd for them, they weren't using the "zero the pages too" variant instead of __get_free_pages() gratuitously. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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