GFP_ZONEMASK is set up as 0xf, meaning the low four bits specify the 
zone type.  As there are only 3 zone types (DMA, NORMAL, & HIGHMEM), and 
only 2 of them (DMA & HIGHMEM) have flags (NORMAL is the default), this 
is wrong.  This simple patch changes one comment, and changes the value 
of GFP_ZONEMASK from 0xf to 0x3.

I'm not sure if this was specified this way to allow for future 
expansion, or what.  If so, please ignore this.  If anyone can tell me 
why this is set to four bits, I'm all ears.

Cheers!

-Matt