Make it clear that the EFI page tables are only available during EFI runtime calls since that subject has come up a fair numbers of times in the past.
Additionally, add the EFI region start and end addresses to the table so that it's possible to see at a glance where they fall in relation to other regions. Reviewed-by: Borislav Petkov <b...@suse.de> Cc: Sai Praneeth Prakhya <sai.praneeth.prak...@intel.com> Cc: Ingo Molnar <mi...@kernel.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Dave Jones <da...@codemonkey.org.uk> Cc: Thomas Gleixner <t...@linutronix.de> Cc: H. Peter Anvin <h...@zytor.com> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Andy Lutomirski <l...@kernel.org> Cc: Denys Vlasenko <dvlas...@redhat.com>, Cc: Stephen Smalley <s...@tycho.nsa.gov> Signed-off-by: Matt Fleming <m...@codeblueprint.co.uk> --- Documentation/x86/x86_64/mm.txt | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt index 05712ac83e38..c518dce7da4d 100644 --- a/Documentation/x86/x86_64/mm.txt +++ b/Documentation/x86/x86_64/mm.txt @@ -16,6 +16,8 @@ ffffec0000000000 - fffffc0000000000 (=44 bits) kasan shadow memory (16TB) ... unused hole ... ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks ... unused hole ... +ffffffef00000000 - ffffffff00000000 (=64 GB) EFI region mapping space +... unused hole ... ffffffff80000000 - ffffffffa0000000 (=512 MB) kernel text mapping, from phys 0 ffffffffa0000000 - ffffffffff5fffff (=1525 MB) module mapping space ffffffffff600000 - ffffffffffdfffff (=8 MB) vsyscalls @@ -32,11 +34,9 @@ reference. Current X86-64 implementations only support 40 bits of address space, but we support up to 46 bits. This expands into MBZ space in the page tables. -->trampoline_pgd: - -We map EFI runtime services in the aforementioned PGD in the virtual -range of 64Gb (arbitrarily set, can be raised if needed) - -0xffffffef00000000 - 0xffffffff00000000 +We map EFI runtime services in the 'efi_pgd' PGD in a 64Gb large virtual +memory window (this size is arbitrary, it can be raised later if needed). +The mappings are not part of any other kernel PGD and are only available +during EFI runtime calls. -Andi Kleen, Jul 2004 -- 2.6.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/