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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BE599C10DC1 for ; Wed, 6 Dec 2023 09:28:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=iV7qaA1J8RXCJlZVNmWa1Sqr4ORGr74rjzdSbrDOgGg=; b=OzS36Y/ntespPN cXp3/oSqXT70dNM7fOG+y9C0HgBMXFcW3CX2CaAdP5DOGzKsz33nzBKv/1J7Ss3Jc7KBBIJuKgo3A 1tYGrS/Q57Pn0nEZHKKzF8GO4IgynOlzKQph1BfOpuSkO0CXWZxEK/tWeg6N7VUWPYj6B2P1mJD3v kqBIYB3PN4dUAAE3BHkMMw0sQh2lVKEEdaeeEFUWx4yl7Bzd7K44q7PqLcPtGbAecqSGh91oZSRVa r8fYFimNA2MZ8gwFoI+ctCUq/czZ7fQU/6ZL/8i0St0pOQbYCJ/T7rAitYV7fLDwonnvAQEKBNn3v xltpuA92gwIOAY2XHBvg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rAoCl-009YSx-1W; Wed, 06 Dec 2023 09:28:31 +0000 Received: from out30-113.freemail.mail.aliyun.com ([115.124.30.113]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rAoCi-009YQy-0F for linux-arm-kernel@lists.infradead.org; Wed, 06 Dec 2023 09:28:29 +0000 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R321e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045192;MF=xueshuai@linux.alibaba.com;NM=1;PH=DS;RN=20;SR=0;TI=SMTPD_---0VxxhQrx_1701854900; Received: from 30.25.233.235(mailfrom:xueshuai@linux.alibaba.com fp:SMTPD_---0VxxhQrx_1701854900) by smtp.aliyun-inc.com; Wed, 06 Dec 2023 17:28:22 +0800 Message-ID: <2c092b76-6b76-4675-94c8-2e4b0031c966@linux.alibaba.com> Date: Wed, 6 Dec 2023 17:28:15 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v11 4/5] drivers/perf: add DesignWare PCIe PMU driver Content-Language: en-US To: Will Deacon , Dan Carpenter Cc: oe-kbuild@lists.linux.dev, ilkka@os.amperecomputing.com, kaishen@linux.alibaba.com, helgaas@kernel.org, yangyicong@huawei.com, Jonathan.Cameron@huawei.com, baolin.wang@linux.alibaba.com, robin.murphy@arm.com, lkp@intel.com, oe-kbuild-all@lists.linux.dev, chengyou@linux.alibaba.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, rdunlap@infradead.org, mark.rutland@arm.com, zhuo.song@linux.alibaba.com, renyu.zj@linux.alibaba.com References: <20231121013400.18367-5-xueshuai@linux.alibaba.com> <2d52f588-f584-4c01-8f41-227815a54e41@suswa.mountain> <20231205142128.GA18450@willie-the-truck> From: Shuai Xue In-Reply-To: <20231205142128.GA18450@willie-the-truck> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231206_012828_423120_34EB06E9 X-CRM114-Status: GOOD ( 10.65 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2023/12/5 22:21, Will Deacon wrote: > On Sat, Nov 25, 2023 at 10:06:39AM +0300, Dan Carpenter wrote: >> Hi Shuai, >> >> kernel test robot noticed the following build warnings: >> >> https://git-scm.com/docs/git-format-patch#_base_tree_information] >> >> url: https://github.com/intel-lab-lkp/linux/commits/Shuai-Xue/docs-perf-Add-description-for-Synopsys-DesignWare-PCIe-PMU-driver/20231121-093713 >> base: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git next >> patch link: https://lore.kernel.org/r/20231121013400.18367-5-xueshuai%40linux.alibaba.com >> patch subject: [PATCH v11 4/5] drivers/perf: add DesignWare PCIe PMU driver >> config: x86_64-randconfig-r071-20231123 (https://download.01.org/0day-ci/archive/20231124/202311241906.0ymlLjyo-lkp@intel.com/config) >> compiler: clang version 16.0.4 (https://github.com/llvm/llvm-project.git ae42196bc493ffe877a7e3dff8be32035dea4d07) >> reproduce: (https://download.01.org/0day-ci/archive/20231124/202311241906.0ymlLjyo-lkp@intel.com/reproduce) >> >> If you fix the issue in a separate patch/commit (i.e. not just a new version of >> the same patch/commit), kindly add following tags >> | Reported-by: kernel test robot >> | Reported-by: Dan Carpenter >> | Closes: https://lore.kernel.org/r/202311241906.0ymlLjyo-lkp@intel.com/ >> >> smatch warnings: >> drivers/perf/dwc_pcie_pmu.c:352 dwc_pcie_pmu_event_update() error: uninitialized symbol 'now'. >> >> vim +/now +352 drivers/perf/dwc_pcie_pmu.c >> >> 3481798a4ec51d1 Shuai Xue 2023-11-21 338 static void dwc_pcie_pmu_event_update(struct perf_event *event) >> 3481798a4ec51d1 Shuai Xue 2023-11-21 339 { >> 3481798a4ec51d1 Shuai Xue 2023-11-21 340 struct hw_perf_event *hwc = &event->hw; >> 3481798a4ec51d1 Shuai Xue 2023-11-21 341 enum dwc_pcie_event_type type = DWC_PCIE_EVENT_TYPE(event); >> 3481798a4ec51d1 Shuai Xue 2023-11-21 342 u64 delta, prev, now; >> 3481798a4ec51d1 Shuai Xue 2023-11-21 343 >> 3481798a4ec51d1 Shuai Xue 2023-11-21 344 do { >> 3481798a4ec51d1 Shuai Xue 2023-11-21 345 prev = local64_read(&hwc->prev_count); >> 3481798a4ec51d1 Shuai Xue 2023-11-21 346 >> 3481798a4ec51d1 Shuai Xue 2023-11-21 347 if (type == DWC_PCIE_LANE_EVENT) >> 3481798a4ec51d1 Shuai Xue 2023-11-21 348 now = dwc_pcie_pmu_read_lane_event_counter(event); >> 3481798a4ec51d1 Shuai Xue 2023-11-21 349 else if (type == DWC_PCIE_TIME_BASE_EVENT) >> 3481798a4ec51d1 Shuai Xue 2023-11-21 350 now = dwc_pcie_pmu_read_time_based_counter(event); >> >> uninitialized on else path. >> >> 3481798a4ec51d1 Shuai Xue 2023-11-21 351 >> 3481798a4ec51d1 Shuai Xue 2023-11-21 @352 } while (local64_cmpxchg(&hwc->prev_count, prev, now) != prev); > > Shuai, any chance you can address this please? I think the event validation > logic means that the type is only ever one of the cases you handle, so > you probably just want to either initialise 'now' to 0 or WARN and return > early if the type is unknown. Hi, Will, and Dan, As the type is checked in dwc_pcie_pmu_event_init(), I will fix this warning by initialising 'now' to 0. Thank you. Best Regards, Shuai _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel