Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754039AbdIFVkD (ORCPT ); Wed, 6 Sep 2017 17:40:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:50254 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753338AbdIFVhJ (ORCPT ); Wed, 6 Sep 2017 17:37:09 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D973321EAA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=luto@kernel.org From: Andy Lutomirski To: x86@kernel.org Cc: linux-kernel@vger.kernel.org, Borislav Petkov , Brian Gerst , Andrew Cooper , Juergen Gross , Boris Ostrovsky , Kees Cook , Andy Lutomirski Subject: [RFC 06/17] x86/asm/64: Use pop instead of movq in syscall_return_via_sysret Date: Wed, 6 Sep 2017 14:36:51 -0700 Message-Id: X-Mailer: git-send-email 2.13.5 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 791 Lines: 34 Saves 64 bytes. Signed-off-by: Andy Lutomirski --- arch/x86/entry/entry_64.S | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 741b7dc1758b..45d4cb8fd81b 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -308,9 +308,17 @@ return_from_SYSCALL_64: */ syscall_return_via_sysret: /* rcx and r11 are already restored (see code above) */ - RESTORE_EXTRA_REGS - RESTORE_C_REGS_EXCEPT_RCX_R11 - movq RSP(%rsp), %rsp + POP_EXTRA_REGS + popq %rsi /* skip r11 */ + popq %r10 + popq %r9 + popq %r8 + popq %rax + popq %rsi /* skip rcx */ + popq %rdx + popq %rsi + popq %rdi + movq RSP-ORIG_RAX(%rsp), %rsp USERGS_SYSRET64 END(entry_SYSCALL_64) -- 2.13.5