Commit b75e2b07 authored Feb 02, 2020 by Arvind Sankar Committed by Ard Biesheuvel Feb 22, 2020

x86/boot: GDT limit value should be size - 1



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@alum.mit.edu>
Link: https://lore.kernel.org/r/20200202171353.3736319-7-nivedita@alum.mit.edu


Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

parent ef5a7b5e

arch/x86/boot/compressed/head_64.S

+2 −2

Original line number	Diff line number	Diff line
		@@ -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 */

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