From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6AD7DC4332F for ; Thu, 24 Nov 2022 02:17:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229520AbiKXCRJ (ORCPT ); Wed, 23 Nov 2022 21:17:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37916 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229445AbiKXCRG (ORCPT ); Wed, 23 Nov 2022 21:17:06 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 19988C6D0C for ; Wed, 23 Nov 2022 18:17:05 -0800 (PST) Received: from kwepemi500022.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4NHhNg2DjVzqSfF; Thu, 24 Nov 2022 10:13:07 +0800 (CST) Received: from [10.67.111.83] (10.67.111.83) by kwepemi500022.china.huawei.com (7.221.188.64) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 24 Nov 2022 10:17:02 +0800 Message-ID: Date: Thu, 24 Nov 2022 10:17:02 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH] arm64: armv8_deprecated: fix unused-function error To: Mark Rutland CC: , , , , References: <20221122032010.202956-1-renzhijie2@huawei.com> <28a90ac0-dc8f-f0dd-74d8-d2884e2cbd30@huawei.com> From: Ren Zhijie In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.111.83] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemi500022.china.huawei.com (7.221.188.64) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2022/11/23 19:01, Mark Rutland 写道: > On Wed, Nov 23, 2022 at 10:06:03AM +0800, Ren Zhijie wrote: >> 在 2022/11/23 0:48, Mark Rutland 写道: >>> On Tue, Nov 22, 2022 at 03:20:10AM +0000, Ren Zhijie wrote: >>>> If CONFIG_SWP_EMULATION is not set and >>>> CONFIG_CP15_BARRIER_EMULATION is not set, >>>> aarch64-linux-gnu complained about unused-function : >>>> >>>> arch/arm64/kernel/armv8_deprecated.c:67:21: error: ‘aarch32_check_condition’ defined but not used [-Werror=unused-function] >>>> static unsigned int aarch32_check_condition(u32 opcode, u32 psr) >>>> ^~~~~~~~~~~~~~~~~~~~~~~ >>>> cc1: all warnings being treated as errors >>>> >>>> To fix this error, warp the definition of >>>> aarch32_check_condition() by defined(CONFIG_SWP_EMULATION) || >>>> defined(CONFIG_CP15_BARRIER_EMULATION) >>>> >>>> Fixes: 0c5f416219da ("arm64: armv8_deprecated: move aarch32 helper earlier") >>> This also depends on building with additional options to turn warnings into >>> errors, no? >> No，i just run the normal command as follow: >> >> make ARCH="arm64" CROSS_COMPILE="aarch64-linux-gnu-" > I think you must also have CONFIG_WERROR enabled? > > Just building defconfig + CONFIG_ARMV8_DEPRECATED=y gives me a warning, but not > an error, and the kernel builds just fine. > > So this is a problem to fix, and I appreciate that in test configs this might > be broken, but it's not a full build-time failure for most users. I get it, thanks a lot! Thanks, Ren > Thanks, > Mark. > >>>> Signed-off-by: Ren Zhijie >>>> --- >>>> arch/arm64/kernel/armv8_deprecated.c | 2 ++ >>>> 1 file changed, 2 insertions(+) >>>> >>>> diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c >>>> index ed0788cf6bbb..3f29ceb6653a 100644 >>>> --- a/arch/arm64/kernel/armv8_deprecated.c >>>> +++ b/arch/arm64/kernel/armv8_deprecated.c >>>> @@ -64,6 +64,7 @@ struct insn_emulation { >>>> #define ARM_OPCODE_CONDITION_UNCOND 0xf >>>> +#if defined(CONFIG_SWP_EMULATION) || defined(CONFIG_CP15_BARRIER_EMULATION) >>>> static unsigned int aarch32_check_condition(u32 opcode, u32 psr) >>>> { >>>> u32 cc_bits = opcode >> 28; >>>> @@ -76,6 +77,7 @@ static unsigned int aarch32_check_condition(u32 opcode, u32 psr) >>>> } >>>> return ARM_OPCODE_CONDTEST_UNCOND; >>>> } >>>> +#endif >>> Could we mark this as '__maybe_unused' or 'inline' instead? I think that's >>> preferable to the ifdeferry. >> sure, i will use __maybe_unused in v2. >> >> Thanks, >> >> Ren. >> >>> Thanks, >>> Mark. >>> >>>> #ifdef CONFIG_SWP_EMULATION >>>> /* >>>> -- >>>> 2.17.1 >>>> >>> . > .