Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751290AbcKAPuM (ORCPT ); Tue, 1 Nov 2016 11:50:12 -0400 Received: from mail-pf0-f196.google.com ([209.85.192.196]:33977 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750712AbcKAPuL (ORCPT ); Tue, 1 Nov 2016 11:50:11 -0400 From: Wei Yang To: hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Wei Yang Subject: [PATCH] x86/boot: reduce one instruction by adding delta to gdtr's base address Date: Tue, 1 Nov 2016 15:49:24 +0000 Message-Id: <1478015364-5547-1-git-send-email-richard.weiyang@gmail.com> X-Mailer: git-send-email 2.5.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 873 Lines: 28 %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. This patch fixes the gdtr's base address by adding delta to it and saves one instruction. Signed-off-by: Wei Yang --- 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 */ -- 2.5.0