x86/efi: Round EFI memmap reservations to EFI_PAGE_SIZE

Mike Galbraith reported that his machine started rebooting during boot
after,

  commit 8e80632fb23f ("efi/esrt: Use efi_mem_reserve() and avoid a kmalloc()")

The ESRT table on his machine is 56 bytes and at no point in the
efi_arch_mem_reserve() call path is that size rounded up to
EFI_PAGE_SIZE, nor is the start address on an EFI_PAGE_SIZE boundary.

Since the EFI memory map only deals with whole pages, inserting an EFI
memory region with 56 bytes results in a new entry covering zero
pages, and completely screws up the calculations for the old regions
that were trimmed.

Round all sizes upwards, and start addresses downwards, to the nearest
EFI_PAGE_SIZE boundary.

Additionally, efi_memmap_insert() expects the mem::range::end value to
be one less than the end address for the region.

Reported-by: Mike Galbraith <[email protected]>
Reported-by: Mike Krinkin <[email protected]>
Tested-by: Mike Krinkin <[email protected]>
Cc: Peter Jones <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Taku Izumi <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>

0 files changed, 0 insertions, 0 deletions