multiboot2: Say that memory maps may not be available on EFI platforms

Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

diff --git a/doc/multiboot.texi b/doc/multiboot.texi
index f7b442d9e7b050a79187f2ab7cb18d95667e8114..1729c855d1cdea68ef2b6c79812d8b7465d85a75 100644 (file)
--- a/doc/multiboot.texi
+++ b/doc/multiboot.texi
@@ -941,6 +941,10 @@ possible value for lower memory is 640 kilobytes. The value returned for
 upper memory is maximally the address of the first upper memory hole
 minus 1 megabyte. It is not guaranteed to be this value.
 
+This tag may not be provided by some boot loaders on EFI platforms if EFI boot
+services are enabled and available for the loaded image (EFI boot services
+not terminated tag exists in Multiboot2 information structure).
+
 @subsection BIOS Boot device
 @example
 @group
@@ -1092,6 +1096,10 @@ indicated a reserved area.
 The map provided is guaranteed to list all standard @sc{ram} that should
 be available for normal use. This type however includes the regions occupied by kernel, mbi, segments and modules. Kernel must take care not to overwrite these regions.
 
+This tag may not be provided by some boot loaders on EFI platforms if EFI boot
+services are enabled and available for the loaded image (EFI boot services
+not terminated tag exists in Multiboot2 information structure).
+
 @subsection Boot loader name
 @example
 @group
@@ -1324,6 +1332,9 @@ u32     | descriptor version|
 
 This tag contains EFI memory map as per EFI specification.
 
+This tag may not be provided by some boot loaders on EFI platforms if EFI boot
+services are enabled and available for the loaded image (EFI boot services
+not terminated tag exists in Multiboot2 information structure).
 
 @subsection EFI boot services not terminated
 @example