Re: [PATCH 28/31] memblock: Export MEMBLOCK_ERROR again

From: H. Peter Anvin
Date: Wed Jul 28 2010 - 01:54:25 EST

On 07/27/2010 10:19 PM, Benjamin Herrenschmidt wrote:
> Screw it, I don't like it but I'll just split your patch in two for now
> and keep 0. It's a bit fishy but memblock does mostly top-down
> allocations and so shouldn't hit 0, and in practice the region at 0 is,
> I beleive, reserved, but we need to be extra careful and might need to
> revisit that a bit.
> That's an area where I don't completely agree with Linus, ie, 0 is a
> perfectly valid physical address for memblock to return :-)

On x86, physical address 0 contains the real-mode IVT and will thus be
reserved, at least for the forseeable future. Other architectures may
very well have non-special RAM there.


H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at