Commit-ID: 064025f7ea1ebcd9bbb99cfa9492a803e8b01d36 Gitweb: http://git.kernel.org/tip/064025f7ea1ebcd9bbb99cfa9492a803e8b01d36 Author: Wei Yang <[email protected]> AuthorDate: Tue, 1 Nov 2016 15:49:24 +0000 Committer: Ingo Molnar <[email protected]> CommitDate: Mon, 7 Nov 2016 08:33:59 +0100
x86/boot: Simplify the GDTR calculation assembly code a bit This patch calculates the GDTR's base address via a single instruction. ( EBP contains the address where it is loaded and GDTR's base address is already set to "gdt" in compilation. It is fine to get the correct base address by adding the delta to GDTR's base address. ) Signed-off-by: Wei Yang <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/boot/compressed/head_64.S | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index efdfba2..4d85e60 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -119,8 +119,7 @@ ENTRY(startup_32) */ /* Load new GDT with the 64bit segments using 32bit descriptor */ - leal gdt(%ebp), %eax - movl %eax, gdt+2(%ebp) + addl %ebp, gdt+2(%ebp) lgdt gdt(%ebp) /* Enable PAE mode */
