Re: [PATCH 0/4] memblock related fixes for -tip

[H. Peter Anvin]

On 10/13/2010 04:14 PM, Jeremy Fitzhardinge wrote:
> 
> The Xen code is setting the max_pfn_mapped correctly, but it is just
> being overridden by:
> 
> 	max_pfn_mapped = KERNEL_IMAGE_SIZE >> PAGE_SHIFT;
> 
> in setup_arch() - and KERNEL_IMAGE_SIZE is hard-coded to 512MB...
> 
> How is this correct?  Does kernel/head_64.S map everything up to 512MB
> or something?
> 

Yes:
        /*
         * 512 MB kernel mapping. We spend a full page on this pagetable
         * anyway.
         *
         * The kernel code+data+bss must not be bigger than that.
         *
         * (NOTE: at +512MB starts the module area, see MODULES_VADDR.
         *  If you want to increase this then increase MODULES_VADDR
         *  too.)
         */
        PMDS(0, __PAGE_KERNEL_LARGE_EXEC,
                KERNEL_IMAGE_SIZE/PMD_SIZE)

This is, however, wrong in the sense that it obviously shouldn't be
getting executed on the Xen codepath.

	-hpa
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/