From patchwork Mon Nov 11 18:40:58 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Martin X-Patchwork-Id: 3169151 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 7532DC045B for ; Mon, 11 Nov 2013 18:41:49 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id B916720173 for ; Mon, 11 Nov 2013 18:41:44 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3884C20172 for ; Mon, 11 Nov 2013 18:41:43 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VfwQW-00039K-LW; Mon, 11 Nov 2013 18:41:32 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VfwQU-00013W-4c; Mon, 11 Nov 2013 18:41:30 +0000 Received: from fw-tnat.cambridge.arm.com ([217.140.96.21] helo=cam-smtp0.cambridge.arm.com) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VfwQP-000131-JN for linux-arm-kernel@lists.infradead.org; Mon, 11 Nov 2013 18:41:27 +0000 Received: from localhost.localdomain (e103592.cambridge.arm.com [10.1.203.45]) by cam-smtp0.cambridge.arm.com (8.13.8/8.13.8) with ESMTP id rABIewIZ014116; Mon, 11 Nov 2013 18:40:59 GMT Date: Mon, 11 Nov 2013 18:40:58 +0000 From: Dave Martin To: Ben Dooks Subject: Re: [PATCH 9/9] ARM: asm/opcodes.h: use ARM_HAVE_INST to use .inst to build instructions Message-ID: <20131111184058.GE3166@localhost.localdomain> References: <1383935832-20865-1-git-send-email-ben.dooks@codethink.co.uk> <1383935832-20865-10-git-send-email-ben.dooks@codethink.co.uk> <20131111161829.GC3166@localhost.localdomain> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20131111161829.GC3166@localhost.localdomain> User-Agent: Mutt/1.5.21 (2010-09-15) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131111_134125_875696_C323830D X-CRM114-Status: GOOD ( 24.52 ) X-Spam-Score: -2.6 (--) Cc: "taras.kondratiuk@linaro.org" , "linux-arm-kernel@lists.infradead.org" , "victor.kamensky@linaro.org" X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On Mon, Nov 11, 2013 at 04:18:30PM +0000, Dave Martin wrote: > On Fri, Nov 08, 2013 at 06:37:12PM +0000, Ben Dooks wrote: > > Currently the header uses .work and .short to build > > .work? :) > > > instructions. This means the output data does not get marked as an > > instruction which can cause issues such as BE8 code failures. > > Are you aware of any actual failures caused by this? > > Use of .short/.long instead of .inst confuses tools like objdump, but > there should be no runtime issue because vmlinux doesn't have the > mapping symbols anyway. If there's an actual bug here, we need to fix > it, though. > > [...] > > Can you have a go with the following patch? > > Beware -- I've not tested it yet... > > From 1978c354e3871bfeecce12d2db66fa4032b1f183 Mon Sep 17 00:00:00 2001 > From: Dave Martin > Date: Mon, 11 Nov 2013 16:13:33 +0000 > Subject: [PATCH] ARM: opcodes: Use .inst to emit instructions if available > > Use of assembler data directives such as .long and .short to emit > instruction opcodes can confuse tools that try to interpret the > linker output, such as disassemblers or debuggers. > [...] > > +#ifdef HAVE_ARM_INST Whoops, that should be ARM_HAVE_INST everywhere... Try this instead: From 8827c8146312e4fd65330767c3d683b3cc48c10d Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Mon, 11 Nov 2013 18:13:47 +0000 Subject: [PATCH v2] ARM: opcodes: Use .inst to emit instructions if available Use of assembler data directives such as .long and .short to emit instruction opcodes can confuse tools that try to interpret the linker output, such as disassemblers or debuggers. Newer versions of the GNU assembler support an .inst directive, which can be used instead to mark the emitted bytes correctly as instructions. This patch makes use of the .inst directive instead of data directives, if available. Signed-off-by: Dave Martin --- arch/arm/include/asm/opcodes.h | 32 +++++++++++++++++++++++++++++--- 1 file changed, 29 insertions(+), 3 deletions(-) diff --git a/arch/arm/include/asm/opcodes.h b/arch/arm/include/asm/opcodes.h index e796c59..96c2c21 100644 --- a/arch/arm/include/asm/opcodes.h +++ b/arch/arm/include/asm/opcodes.h @@ -199,12 +199,18 @@ extern asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr); */ #include +#ifdef ARM_HAVE_INST +#define __inst_arm(x) ___inst_arm(x) +#define __inst_thumb32(x) ___inst_thumb32(x) +#define __inst_thumb16(x) ___inst_thumb16(x) +#else /* ! ARM_HAVE_INST */ #define __inst_arm(x) ___inst_arm(___asm_opcode_to_mem_arm(x)) #define __inst_thumb32(x) ___inst_thumb32( \ ___asm_opcode_to_mem_thumb16(___asm_opcode_thumb32_first(x)), \ ___asm_opcode_to_mem_thumb16(___asm_opcode_thumb32_second(x)) \ ) #define __inst_thumb16(x) ___inst_thumb16(___asm_opcode_to_mem_thumb16(x)) +#endif /* ! ARM_HAVE_INST */ #ifdef CONFIG_THUMB2_KERNEL #define __inst_arm_thumb16(arm_opcode, thumb_opcode) \ @@ -216,16 +222,36 @@ extern asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr); #define __inst_arm_thumb32(arm_opcode, thumb_opcode) __inst_arm(arm_opcode) #endif -/* Helpers for the helpers. Don't use these directly. */ +/* + * Helpers for the helpers. Don't use these directly. + * Note that the interface for these depends on whether or not ARM_HAVE_INST + * is defined. + */ #ifdef __ASSEMBLY__ + +#ifdef ARM_HAVE_INST +#define ___inst_arm(x) .inst x +#define ___inst_thumb16(x) .inst.n x +#define ___inst_thumb32(x) .inst.w x +#else /* ! ARM_HAVE_INST */ #define ___inst_arm(x) .long x #define ___inst_thumb16(x) .short x #define ___inst_thumb32(first, second) .short first, second -#else +#endif /* ! ARM_HAVE_INST */ + +#else /* ! __ASSEMBLY__ */ + +#ifdef ARM_HAVE_INST +#define ___inst_arm(x) ".inst " __stringify(x) "\n\t" +#define ___inst_thumb16(x) ".inst.n " __stringify(x) "\n\t" +#define ___inst_thumb32(x) ".inst.w " __stringify(x) "\n\t" +#else /* ! ARM_HAVE_INST */ #define ___inst_arm(x) ".long " __stringify(x) "\n\t" #define ___inst_thumb16(x) ".short " __stringify(x) "\n\t" #define ___inst_thumb32(first, second) \ ".short " __stringify(first) ", " __stringify(second) "\n\t" -#endif +#endif /* ! ARM_HAVE_INST */ + +#endif /* ! __ASSEMBLY__ */ #endif /* __ASM_ARM_OPCODES_H */