From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755599AbdKBKzr (ORCPT ); Thu, 2 Nov 2017 06:55:47 -0400 Received: from terminus.zytor.com ([65.50.211.136]:50379 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755568AbdKBKzo (ORCPT ); Thu, 2 Nov 2017 06:55:44 -0400 Date: Thu, 2 Nov 2017 03:51:08 -0700 From: tip-bot for Andy Lutomirski Message-ID: Cc: mingo@kernel.org, brgerst@gmail.com, torvalds@linux-foundation.org, hpa@zytor.com, luto@kernel.org, bpetkov@suse.de, linux-kernel@vger.kernel.org, peterz@infradead.org, dave.hansen@intel.com, tglx@linutronix.de, bp@suse.de Reply-To: bpetkov@suse.de, dave.hansen@intel.com, peterz@infradead.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, bp@suse.de, hpa@zytor.com, luto@kernel.org, brgerst@gmail.com, torvalds@linux-foundation.org, mingo@kernel.org In-Reply-To: <6609b7f74ab31c36604ad746e019ea8495aec76c.1509609304.git.luto@kernel.org> References: <6609b7f74ab31c36604ad746e019ea8495aec76c.1509609304.git.luto@kernel.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/asm] x86/entry/64: Use pop instead of movq in syscall_return_via_sysret Git-Commit-ID: 4fbb39108f972437c44e5ffa781b56635d496826 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 4fbb39108f972437c44e5ffa781b56635d496826 Gitweb: https://git.kernel.org/tip/4fbb39108f972437c44e5ffa781b56635d496826 Author: Andy Lutomirski AuthorDate: Thu, 2 Nov 2017 00:59:03 -0700 Committer: Ingo Molnar CommitDate: Thu, 2 Nov 2017 11:04:39 +0100 x86/entry/64: Use pop instead of movq in syscall_return_via_sysret Saves 64 bytes. Signed-off-by: Andy Lutomirski Reviewed-by: Borislav Petkov Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/6609b7f74ab31c36604ad746e019ea8495aec76c.1509609304.git.luto@kernel.org Signed-off-by: Ingo Molnar --- 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 15539644..4f9b446 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -315,10 +315,18 @@ 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 UNWIND_HINT_EMPTY + 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)