From: "H. Peter Anvin" <hpa@xxxxxxxxx> Date: Tue, 27 Jul 2010 22:53:21 -0700 > 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. 0 is very much possible on sparc64 -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html