[PATCH] kdump: Fix invalid access on i386 sparsemem.

[Ingo Molnar]

* Ken'ichi Ohmichi <oomichi at mxs.nes.nec.co.jp> wrote:

> 
> Hi,
> 
> Since linux-2.6.27, kdump has failed on i386 sparsemem kernel.
> 1st-kernel gets a panic just before switching to 2nd-kernel.
> 
> The cause is that a kernel accesses invalid mem_section by
> page_to_pfn(image->swap_page) at machine_kexec().
> image->swap_page is allocated if kexec for hibernation, but
> it is not allocated if kdump. So if kdump, a kernel should
> not access the mem_section corresponding to image->swap_page.
> The attached patch fixes this invalid access.

applied to tip/x86/urgent, thanks!

	Ingo