From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933224AbcA3SlT (ORCPT ); Sat, 30 Jan 2016 13:41:19 -0500 Received: from terminus.zytor.com ([198.137.202.10]:41272 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932574AbcA3SlS (ORCPT ); Sat, 30 Jan 2016 13:41:18 -0500 User-Agent: K-9 Mail for Android In-Reply-To: References: <58d4a95f40e43b894f93288b4a3633963d0ee22e.1454022279.git.luto@kernel.org> <726983A1-F3A9-476B-AAA2-871F0561CB47@zytor.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Subject: Re: [tip:x86/asm] x86/syscalls: Remove __SYSCALL_COMMON and __SYSCALL_X32 From: "H. Peter Anvin" Date: Sat, 30 Jan 2016 10:40:00 -0800 To: Brian Gerst CC: linux-tip-commits@vger.kernel.org, tip-bot for Andy Lutomirski , Linus Torvalds , Andy Lutomirski , Borislav Petkov , Andy Lutomirski , Linux Kernel Mailing List , Ingo Molnar , Thomas Gleixner , Denys Vlasenko , Peter Zijlstra , =?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?= Message-ID: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On January 29, 2016 2:19:29 PM PST, Brian Gerst wrote: >On Fri, Jan 29, 2016 at 4:23 PM, H. Peter Anvin wrote: >> On January 29, 2016 3:34:44 AM PST, tip-bot for Andy Lutomirski > wrote: >>>Commit-ID: 32324ce15ea8cb4c8acc28acb2fd36fabf73e9db >>>Gitweb: >>>http://git.kernel.org/tip/32324ce15ea8cb4c8acc28acb2fd36fabf73e9db >>>Author: Andy Lutomirski >>>AuthorDate: Thu, 28 Jan 2016 15:11:22 -0800 >>>Committer: Ingo Molnar >>>CommitDate: Fri, 29 Jan 2016 09:46:37 +0100 >>> >>>x86/syscalls: Remove __SYSCALL_COMMON and __SYSCALL_X32 >>> >>>The common/64/x32 distinction has no effect other than >>>determining which kernels actually support the syscall. Move >>>the logic into syscalltbl.sh. >>> >>>Signed-off-by: Andy Lutomirski >>>Cc: Andy Lutomirski >>>Cc: Borislav Petkov >>>Cc: Brian Gerst >>>Cc: Denys Vlasenko >>>Cc: Frederic Weisbecker >>>Cc: H. Peter Anvin >>>Cc: Linus Torvalds >>>Cc: Peter Zijlstra >>>Cc: Thomas Gleixner >>>Link: >>>http://lkml.kernel.org/r/58d4a95f40e43b894f93288b4a3633963d0ee22e.1454022279.git.luto@kernel.org >>>Signed-off-by: Ingo Molnar >>>--- >>> arch/x86/entry/syscall_64.c | 8 -------- >>> arch/x86/entry/syscalls/syscalltbl.sh | 17 ++++++++++++++++- >>> arch/x86/kernel/asm-offsets_64.c | 6 ------ >>> arch/x86/um/sys_call_table_64.c | 3 --- >>> arch/x86/um/user-offsets.c | 2 -- >>> 5 files changed, 16 insertions(+), 20 deletions(-) >>> >>>diff --git a/arch/x86/entry/syscall_64.c >b/arch/x86/entry/syscall_64.c >>>index 41283d2..974fd89 100644 >>>--- a/arch/x86/entry/syscall_64.c >>>+++ b/arch/x86/entry/syscall_64.c >>>@@ -6,14 +6,6 @@ >>> #include >>> #include >>> >>>-#define __SYSCALL_COMMON(nr, sym, compat) __SYSCALL_64(nr, sym, >>>compat) >>>- >>>-#ifdef CONFIG_X86_X32_ABI >>>-# define __SYSCALL_X32(nr, sym, compat) __SYSCALL_64(nr, sym, >compat) >>>-#else >>>-# define __SYSCALL_X32(nr, sym, compat) /* nothing */ >>>-#endif >>>- >>>#define __SYSCALL_64(nr, sym, compat) extern asmlinkage long >>>sym(unsigned long, unsigned long, unsigned long, unsigned long, >>>unsigned long, unsigned long) ; >>> #include >>> #undef __SYSCALL_64 >>>diff --git a/arch/x86/entry/syscalls/syscalltbl.sh >>>b/arch/x86/entry/syscalls/syscalltbl.sh >>>index 167965e..5ebeaf1 100644 >>>--- a/arch/x86/entry/syscalls/syscalltbl.sh >>>+++ b/arch/x86/entry/syscalls/syscalltbl.sh >>>@@ -18,6 +18,21 @@ emit() { >>> grep '^[0-9]' "$in" | sort -n | ( >>> while read nr abi name entry compat; do >>> abi=`echo "$abi" | tr '[a-z]' '[A-Z]'` >>>- emit "$abi" "$nr" "$entry" "$compat" >>>+ if [ "$abi" == "COMMON" -o "$abi" == "64" ]; then >>>+ # COMMON is the same as 64, except that we don't expect >X32 >>>+ # programs to use it. Our expectation has nothing to do >with >>>+ # any generated code, so treat them the same. >>>+ emit 64 "$nr" "$entry" "$compat" >>>+ elif [ "$abi" == "X32" ]; then >>>+ # X32 is equivalent to 64 on an X32-compatible kernel. >>>+ echo "#ifdef CONFIG_X86_X32_ABI" >>>+ emit 64 "$nr" "$entry" "$compat" >>>+ echo "#endif" >>>+ elif [ "$abi" == "I386" ]; then >>>+ emit "$abi" "$nr" "$entry" "$compat" >>>+ else >>>+ echo "Unknown abi $abi" >&2 >>>+ exit 1 >>>+ fi >>> done >>> ) > "$out" >>>diff --git a/arch/x86/kernel/asm-offsets_64.c >>>b/arch/x86/kernel/asm-offsets_64.c >>>index f2edafb..29db3b3 100644 >>>--- a/arch/x86/kernel/asm-offsets_64.c >>>+++ b/arch/x86/kernel/asm-offsets_64.c >>>@@ -5,12 +5,6 @@ >>> #include >>> >>> #define __SYSCALL_64(nr, sym, compat) [nr] = 1, >>>-#define __SYSCALL_COMMON(nr, sym, compat) [nr] = 1, >>>-#ifdef CONFIG_X86_X32_ABI >>>-# define __SYSCALL_X32(nr, sym, compat) [nr] = 1, >>>-#else >>>-# define __SYSCALL_X32(nr, sym, compat) /* nothing */ >>>-#endif >>> static char syscalls_64[] = { >>> #include >>> }; >>>diff --git a/arch/x86/um/sys_call_table_64.c >>>b/arch/x86/um/sys_call_table_64.c >>>index b74ea6c..71a497c 100644 >>>--- a/arch/x86/um/sys_call_table_64.c >>>+++ b/arch/x86/um/sys_call_table_64.c >>>@@ -35,9 +35,6 @@ >>> #define stub_execveat sys_execveat >>> #define stub_rt_sigreturn sys_rt_sigreturn >>> >>>-#define __SYSCALL_COMMON(nr, sym, compat) __SYSCALL_64(nr, sym, >>>compat) >>>-#define __SYSCALL_X32(nr, sym, compat) /* Not supported */ >>>- >>>#define __SYSCALL_64(nr, sym, compat) extern asmlinkage long >>>sym(unsigned long, unsigned long, unsigned long, unsigned long, >>>unsigned long, unsigned long) ; >>> #include >>> >>>diff --git a/arch/x86/um/user-offsets.c b/arch/x86/um/user-offsets.c >>>index ce7e360..5edf4f4 100644 >>>--- a/arch/x86/um/user-offsets.c >>>+++ b/arch/x86/um/user-offsets.c >>>@@ -15,8 +15,6 @@ static char syscalls[] = { >>> }; >>> #else >>> #define __SYSCALL_64(nr, sym, compat) [nr] = 1, >>>-#define __SYSCALL_COMMON(nr, sym, compat) [nr] = 1, >>>-#define __SYSCALL_X32(nr, sym, compat) /* Not supported */ >>> static char syscalls[] = { >>> #include >>> }; >> >> I am really unhappy about this change. syscalltbl.sh is written so >that other architectures can use it, and so I would really prefer for >it to stay arch-neutral and encourage other arches to use it, too. > >We could use a qualifier (ie. /x32 or /x32ptregs) instead. > >-- >Brian Gerst I like that idea much better. -- Sent from my Android device with K-9 Mail. Please excuse brevity and formatting.