From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753880Ab2IZKRX (ORCPT ); Wed, 26 Sep 2012 06:17:23 -0400 Received: from nat28.tlf.novell.com ([130.57.49.28]:32859 "EHLO nat28.tlf.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752776Ab2IZKRV convert rfc822-to-8bit (ORCPT ); Wed, 26 Sep 2012 06:17:21 -0400 Message-Id: <5062F267020000780009DF06@nat28.tlf.novell.com> X-Mailer: Novell GroupWise Internet Agent 12.0.0 Date: Wed, 26 Sep 2012 11:17:43 +0100 From: "Jan Beulich" To: "Tao Guo" Cc: "Ingo Molnar" , , , Subject: Re: [PATCH] x86_64: Work around old gas bug References: <1348648102-12653-1-git-send-email-glorioustao@gmail.com> In-Reply-To: <1348648102-12653-1-git-send-email-glorioustao@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8BIT Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>> On 26.09.12 at 10:28, Tao Guo wrote: > gas in binutils(2.16.91) could not parse parentheses within macro > parameters unless fully parenthesized, and this is a workaround to > make old gas work without generating below errors: > arch/x86/kernel/entry_64.S: Assembler messages: > arch/x86/kernel/entry_64.S:387: Error: too many positional arguments > arch/x86/kernel/entry_64.S:389: Error: too many positional arguments > arch/x86/kernel/entry_64.S:390: Error: too many positional arguments > arch/x86/kernel/entry_64.S:391: Error: too many positional arguments > arch/x86/kernel/entry_64.S:392: Error: too many positional arguments > arch/x86/kernel/entry_64.S:393: Error: too many positional arguments > arch/x86/kernel/entry_64.S:394: Error: too many positional arguments > > Signed-off-by: Tao Guo This looks okay now to me, but I'm somewhat reluctant to formally ack it given that we know how broken those particular gas versions are. Jan > --- > arch/x86/include/asm/calling.h | 48 +++++++++++++++++++-------------------- > arch/x86/kernel/entry_64.S | 20 ++++++++-------- > 2 files changed, 33 insertions(+), 35 deletions(-) > > diff --git a/arch/x86/include/asm/calling.h b/arch/x86/include/asm/calling.h > index a9e3a74..7f8422a 100644 > --- a/arch/x86/include/asm/calling.h > +++ b/arch/x86/include/asm/calling.h > @@ -49,38 +49,36 @@ For 32-bit we have the following conventions - kernel is > built with > #include "dwarf2.h" > > /* > - * 64-bit system call stack frame layout defines and helpers, for > - * assembly code (note that the seemingly unnecessary parentheses > - * are to prevent cpp from inserting spaces in expressions that get > - * passed to macros): > + * 64-bit system call stack frame layout defines and helpers, > + * for assembly code: > */ > > -#define R15 (0) > -#define R14 (8) > -#define R13 (16) > -#define R12 (24) > -#define RBP (32) > -#define RBX (40) > +#define R15 0 > +#define R14 8 > +#define R13 16 > +#define R12 24 > +#define RBP 32 > +#define RBX 40 > > /* arguments: interrupts/non tracing syscalls only save up to here: */ > -#define R11 (48) > -#define R10 (56) > -#define R9 (64) > -#define R8 (72) > -#define RAX (80) > -#define RCX (88) > -#define RDX (96) > -#define RSI (104) > -#define RDI (112) > -#define ORIG_RAX (120) /* + error_code */ > +#define R11 48 > +#define R10 56 > +#define R9 64 > +#define R8 72 > +#define RAX 80 > +#define RCX 88 > +#define RDX 96 > +#define RSI 104 > +#define RDI 112 > +#define ORIG_RAX 120 /* + error_code */ > /* end of arguments */ > > /* cpu exception frame or undefined in case of fast syscall: */ > -#define RIP (128) > -#define CS (136) > -#define EFLAGS (144) > -#define RSP (152) > -#define SS (160) > +#define RIP 128 > +#define CS 136 > +#define EFLAGS 144 > +#define RSP 152 > +#define SS 160 > > #define ARGOFFSET R11 > #define SWFRAME ORIG_RAX > diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S > index 69babd8..bf77e70 100644 > --- a/arch/x86/kernel/entry_64.S > +++ b/arch/x86/kernel/entry_64.S > @@ -342,15 +342,15 @@ ENDPROC(native_usergs_sysret64) > .macro SAVE_ARGS_IRQ > cld > /* start from rbp in pt_regs and jump over */ > - movq_cfi rdi, RDI-RBP > - movq_cfi rsi, RSI-RBP > - movq_cfi rdx, RDX-RBP > - movq_cfi rcx, RCX-RBP > - movq_cfi rax, RAX-RBP > - movq_cfi r8, R8-RBP > - movq_cfi r9, R9-RBP > - movq_cfi r10, R10-RBP > - movq_cfi r11, R11-RBP > + movq_cfi rdi, (RDI-RBP) > + movq_cfi rsi, (RSI-RBP) > + movq_cfi rdx, (RDX-RBP) > + movq_cfi rcx, (RCX-RBP) > + movq_cfi rax, (RAX-RBP) > + movq_cfi r8, (R8-RBP) > + movq_cfi r9, (R9-RBP) > + movq_cfi r10, (R10-RBP) > + movq_cfi r11, (R11-RBP) > > /* Save rbp so that we can unwind from get_irq_regs() */ > movq_cfi rbp, 0 > @@ -384,7 +384,7 @@ ENDPROC(native_usergs_sysret64) > .endm > > ENTRY(save_rest) > - PARTIAL_FRAME 1 REST_SKIP+8 > + PARTIAL_FRAME 1 (REST_SKIP+8) > movq 5*8+16(%rsp), %r11 /* save return address */ > movq_cfi rbx, RBX+16 > movq_cfi rbp, RBP+16 > -- > 1.7.7.6