Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964803AbbDIJFK (ORCPT ); Thu, 9 Apr 2015 05:05:10 -0400 Received: from terminus.zytor.com ([198.137.202.10]:51911 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932563AbbDIJEr (ORCPT ); Thu, 9 Apr 2015 05:04:47 -0400 Date: Thu, 9 Apr 2015 02:04:07 -0700 From: tip-bot for Denys Vlasenko Message-ID: Cc: oleg@redhat.com, torvalds@linux-foundation.org, tglx@linutronix.de, brgerst@gmail.com, wad@chromium.org, luto@amacapital.net, linux-kernel@vger.kernel.org, keescook@chromium.org, dvlasenk@redhat.com, ast@plumgrid.com, mingo@kernel.org, bp@alien8.de, rostedt@goodmis.org, fweisbec@gmail.com, hpa@zytor.com Reply-To: oleg@redhat.com, wad@chromium.org, brgerst@gmail.com, luto@amacapital.net, torvalds@linux-foundation.org, tglx@linutronix.de, keescook@chromium.org, dvlasenk@redhat.com, mingo@kernel.org, ast@plumgrid.com, linux-kernel@vger.kernel.org, fweisbec@gmail.com, hpa@zytor.com, bp@alien8.de, rostedt@goodmis.org In-Reply-To: <1428439424-7258-8-git-send-email-dvlasenk@redhat.com> References: <1428439424-7258-8-git-send-email-dvlasenk@redhat.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/asm] x86/asm/entry/64: Reduce padding in execve stubs Git-Commit-ID: a37f34a325d90856314ccd4994e1070dcc6bdcc4 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: 2901 Lines: 98 Commit-ID: a37f34a325d90856314ccd4994e1070dcc6bdcc4 Gitweb: http://git.kernel.org/tip/a37f34a325d90856314ccd4994e1070dcc6bdcc4 Author: Denys Vlasenko AuthorDate: Tue, 7 Apr 2015 22:43:44 +0200 Committer: Ingo Molnar CommitDate: Thu, 9 Apr 2015 10:31:26 +0200 x86/asm/entry/64: Reduce padding in execve stubs execve stubs are 7 bytes only. Padding them to 16 bytes is a waste. text data bss dec hex filename 12594 0 0 12594 3132 entry_64.o.before 12530 0 0 12530 30f2 entry_64.o 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/1428439424-7258-8-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/entry_64.S | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index b67f2fc..c7b2384 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -511,8 +511,12 @@ return_from_execve: jmp int_ret_from_sys_call CFI_ENDPROC END(stub_execve) - -ENTRY(stub_execveat) +/* + * Remaining execve stubs are only 7 bytes long. + * ENTRY() often aligns to 16 bytes, which in this case has no benefits. + */ + .align 8 +GLOBAL(stub_execveat) CFI_STARTPROC DEFAULT_FRAME 0, 8 call sys_execveat @@ -521,14 +525,16 @@ ENTRY(stub_execveat) END(stub_execveat) #ifdef CONFIG_X86_X32_ABI -ENTRY(stub_x32_execve) + .align 8 +GLOBAL(stub_x32_execve) CFI_STARTPROC DEFAULT_FRAME 0, 8 call compat_sys_execve jmp return_from_execve CFI_ENDPROC END(stub_x32_execve) -ENTRY(stub_x32_execveat) + .align 8 +GLOBAL(stub_x32_execveat) CFI_STARTPROC DEFAULT_FRAME 0, 8 call compat_sys_execveat @@ -538,13 +544,15 @@ END(stub_x32_execveat) #endif #ifdef CONFIG_IA32_EMULATION -ENTRY(stub32_execve) + .align 8 +GLOBAL(stub32_execve) CFI_STARTPROC call compat_sys_execve jmp return_from_execve CFI_ENDPROC END(stub32_execve) -ENTRY(stub32_execveat) + .align 8 +GLOBAL(stub32_execveat) CFI_STARTPROC call compat_sys_execveat jmp return_from_execve -- 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/