[PATCH 8/8] Documentation/x86/boot: Correct segment requirements for 64-bit boot

[Arvind Sankar <nivedita@alum.mit.edu>]

64-bit mode has no segment/GDT requirements as it does not really use
segment registers. The entry code loads null descriptors into the data
and stack segment registers.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
---
 Documentation/x86/boot.rst | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/Documentation/x86/boot.rst b/Documentation/x86/boot.rst
index 3e13b7d57271..df2bf8abbbc1 100644
--- a/Documentation/x86/boot.rst
+++ b/Documentation/x86/boot.rst
@@ -1396,12 +1396,9 @@ In 64-bit boot protocol, the kernel is started by jumping to the
 At entry, the CPU must be in 64-bit mode with paging enabled.
 The range with setup_header.init_size from start address of loaded
 kernel and zero page and command line buffer get ident mapping;
-a GDT must be loaded with the descriptors for selectors
-__BOOT_CS(0x10) and __BOOT_DS(0x18); both descriptors must be 4G flat
-segment; __BOOT_CS must have execute/read permission, and __BOOT_DS
-must have read/write permission; CS must be __BOOT_CS and DS, ES, SS
-must be __BOOT_DS; interrupt must be disabled; %rsi must hold the base
-address of the struct boot_params.
+interrupt must be disabled; %rsi must hold the base address of the
+struct boot_params. As 64-bit mode does not really use segments, there
+are no special requirements on the segment registers or descriptors.
 
 EFI Handover Protocol
 =====================
-- 
2.24.1