x86/mm: Update memory map description to list hypervisor-reserved area
authorDave Hansen <dave.hansen@linux.intel.com>
Thu, 18 Sep 2014 19:56:06 +0000 (12:56 -0700)
committerIngo Molnar <mingo@kernel.org>
Fri, 19 Sep 2014 10:48:02 +0000 (12:48 +0200)
commitbeb9147e95a75f41c984d7235cf6d59f3ca2d5db
treed1cc1f24978e29bb2c51149cfe8cc6a6df854971
parent84779575554e2a19b9f6fc8d44f9763546a822ad
x86/mm: Update memory map description to list hypervisor-reserved area

Peter Anvin says:

 > 0xffff880000000000 is the lowest usable address because we have
 > agreed to leave 0xffff800000000000-0xffff880000000000 for the
 > hypervisor or other non-OS uses.

Let's call this out in the documentation.

This came up during the kernel address sanitizer discussions
where it was proposed to use this area for other kernel things.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Link: http://lkml.kernel.org/r/20140918195606.841389D2@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Documentation/x86/x86_64/mm.txt