[PATCH v2 6/7] x86/boot: GDT limit value should be size - 1

From: Arvind Sankar
Date: Sun Feb 02 2020 - 12:14:27 EST


The limit value for the GDTR should be such that adding it to the base
address gives the address of the last byte of the GDT, i.e. it should be
one less than the size, not the size.

Signed-off-by: Arvind Sankar <nivedita@xxxxxxxxxxxx>
---
arch/x86/boot/compressed/head_64.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 69cc6c68741e..c36e6156b6a3 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -624,12 +624,12 @@ SYM_FUNC_END(.Lno_longmode)

.data
SYM_DATA_START_LOCAL(gdt64)
- .word gdt_end - gdt
+ .word gdt_end - gdt - 1
.quad 0
SYM_DATA_END(gdt64)
.balign 8
SYM_DATA_START_LOCAL(gdt)
- .word gdt_end - gdt
+ .word gdt_end - gdt - 1
.long gdt
.word 0
.quad 0x00cf9a000000ffff /* __KERNEL32_CS */
--
2.24.1