x86 boot: allow overlapping early reserve memory ranges

Add support for overlapping early memory reservations.

In general, they still can't overlap, and will panic
with "Overlapping early reservations" if they do overlap.

But if a memory range is reserved with the new call:
    reserve_early_overlap_ok()
rather than with the usual call:
    reserve_early()
then subsequent early reservations are allowed to overlap.

This new reserve_early_overlap_ok() call is only used in one
place so far, which is the "BIOS reserved" reservation for the
the EBDA region, which out of Paranoia reserves more than what
the BIOS might have specified, and which thus might overlap with
another legitimate early memory reservation (such as, perhaps,
the EFI memmap.)

Signed-off-by: Paul Jackson <[email protected]>
Cc: "Yinghai Lu" <[email protected]>
Cc: "Jack Steiner" <[email protected]>
Cc: "Mike Travis" <[email protected]>
Cc: "Huang
Cc: Ying" <[email protected]>
Cc: "Andi Kleen" <[email protected]>
Cc: "Andrew Morton" <[email protected]>
Cc: Paul Jackson <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

0 files changed, 0 insertions, 0 deletions