On Tue, 2010-07-27 at 22:53 -0700, H. Peter Anvin wrote: > 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. Right, that's my point. Anyways, I'm making 0 special for now and adding a wart to prevent the allocator from returning something below PAGE_SIZE. If we want to revisit that later we can. Cheers, Ben. -- 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
