o Relocatable bzImage support had got rid of CONFIG_PHYSICAL_START option
  thinking that now this option is not required as people can build a
  second kernel as relocatable and load it anywhere. So need of compiling
  the kernel for a custom address was gone. But Magnus uses vmlinux images
  for second kernel in Xen environment and he wants to continue to use
  it.

o Restoring the CONFIG_PHYSICAL_START option for the time being. I think
  down the line we can get rid of it.
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>