> The port sharing feature mixed kernel virtual addresses as well as > physical addresses for the offset used to describe the mmap address to map > the InfiniPath hardware into user space. This had a conflict on powerpc. > The new scheme converts it to a physical address so it doesn't conflict > with chip addresses and yet still fits in 40/44 bits so it isn't truncated > by 32-bit applications calling mmap64().
> +/* > + * Convert kernel virtual addresses to physical addresses so they don't > + * potentially conflict with the chip addresses used as mmap offsets. > + * It doesn't really matter what mmap offset we use as long as we can > + * interpret it correctly. > + */ > + paddr = page_to_pfn(page) << PAGE_SHIFT; > + > + return paddr; what guarantee is there that physical addresses fit into any number of bits? Couldn't I have a NUMA system or something that puts physical memory starting at an offset of 1 << 48 or whatever? - R. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
