Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934008AbbDIJEO (ORCPT ); Thu, 9 Apr 2015 05:04:14 -0400 Received: from terminus.zytor.com ([198.137.202.10]:51879 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932674AbbDIJEJ (ORCPT ); Thu, 9 Apr 2015 05:04:09 -0400 Date: Thu, 9 Apr 2015 02:03:29 -0700 From: tip-bot for Denys Vlasenko Message-ID: Cc: wad@chromium.org, ast@plumgrid.com, mingo@kernel.org, linux-kernel@vger.kernel.org, hpa@zytor.com, luto@amacapital.net, torvalds@linux-foundation.org, dvlasenk@redhat.com, keescook@chromium.org, brgerst@gmail.com, fweisbec@gmail.com, oleg@redhat.com, rostedt@goodmis.org, bp@alien8.de, tglx@linutronix.de Reply-To: dvlasenk@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, luto@amacapital.net, torvalds@linux-foundation.org, mingo@kernel.org, wad@chromium.org, ast@plumgrid.com, tglx@linutronix.de, oleg@redhat.com, fweisbec@gmail.com, rostedt@goodmis.org, bp@alien8.de, keescook@chromium.org, brgerst@gmail.com In-Reply-To: <1428439424-7258-6-git-send-email-dvlasenk@redhat.com> References: <1428439424-7258-6-git-send-email-dvlasenk@redhat.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/asm] x86/asm/entry/64: Simplify jumps in ret_from_fork Git-Commit-ID: 66ad4efa51805964521db03d8aa827a8dd9058b9 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 Content-Length: 2312 Lines: 72 Commit-ID: 66ad4efa51805964521db03d8aa827a8dd9058b9 Gitweb: http://git.kernel.org/tip/66ad4efa51805964521db03d8aa827a8dd9058b9 Author: Denys Vlasenko AuthorDate: Tue, 7 Apr 2015 22:43:42 +0200 Committer: Ingo Molnar CommitDate: Thu, 9 Apr 2015 10:31:25 +0200 x86/asm/entry/64: Simplify jumps in ret_from_fork Replace test jz 1f jmp label 1: with test jnz label Run-tested. Signed-off-by: Denys Vlasenko Cc: Alexei Starovoitov Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Kees Cook Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Will Drewry Link: http://lkml.kernel.org/r/1428439424-7258-6-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/entry_64.S | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index e8ddd51..a35e5e4 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -608,18 +608,18 @@ ENTRY(ret_from_fork) RESTORE_EXTRA_REGS testl $3,CS(%rsp) # from kernel_thread? - jz 1f /* * By the time we get here, we have no idea whether our pt_regs, * ti flags, and ti status came from the 64-bit SYSCALL fast path, * the slow path, or one of the ia32entry paths. - * Use int_ret_from_sys_call to return, since it can safely handle + * Use IRET code path to return, since it can safely handle * all of the above. */ - jmp int_ret_from_sys_call + jnz int_ret_from_sys_call -1: + /* We came from kernel_thread */ + /* nb: we depend on RESTORE_EXTRA_REGS above */ movq %rbp, %rdi call *%rbx movl $0, RAX(%rsp) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/