This reverts commit d1a8d66b91.
Ard reported a boot failure when running UEFI under Qemu and Xen and
experimenting with various Tianocore build options,
"As it turns out, when allocating room for the UEFI memory map using
UEFI's AllocatePool (), it may result in two new memory map entries
being created, for instance, when using Tianocore's preallocated region
feature. For example, the following region
0x00005ead5000-0x00005ebfffff [Conventional Memory| | | | | |WB|WT|WC|UC]
may be split like this
0x00005ead5000-0x00005eae2fff [Conventional Memory| | | | | |WB|WT|WC|UC]
0x00005eae3000-0x00005eae4fff [Loader Data | | | | | |WB|WT|WC|UC]
0x00005eae5000-0x00005ebfffff [Conventional Memory| | | | | |WB|WT|WC|UC]
if the preallocated Loader Data region was chosen to be right in the
middle of the original free space.
After patch d1a8d66b91 ("efi/libstub: Call get_memory_map() to
obtain map and desc sizes"), this is not being dealt with correctly
anymore, as the existing logic to allocate room for a single additional
entry has become insufficient."
Mark requested to reinstate the old loop we had before commit
d1a8d66b91, which grows the memory map buffer until it's big enough to
hold the EFI memory map.
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
43a9f69692