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Wed, 28 Jul 2021 07:47:06 +0000 Date: Wed, 28 Jul 2021 10:46:48 +0300 From: Dan Carpenter To: Anitha Chrisanthus Subject: Re: [PATCH 12/14] drm/kmb: Fix possible oops in error handling Message-ID: <20210728074648.GS25548@kadam> References: <20210728003126.1425028-1-anitha.chrisanthus@intel.com> <20210728003126.1425028-12-anitha.chrisanthus@intel.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210728003126.1425028-12-anitha.chrisanthus@intel.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-ClientProxiedBy: JN2P275CA0044.ZAFP275.PROD.OUTLOOK.COM (2603:1086:0:2::32) To MWHPR1001MB2365.namprd10.prod.outlook.com (2603:10b6:301:2d::28) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from kadam (102.222.70.252) by JN2P275CA0044.ZAFP275.PROD.OUTLOOK.COM (2603:1086:0:2::32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4373.18 via Frontend Transport; Wed, 28 Jul 2021 07:47:02 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 93e4c487-e636-4734-644d-08d9519be55c X-MS-TrafficTypeDiagnostic: CO1PR10MB4721: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:1051; 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> > /* Unregister DSI host */ > - kmb_dsi_host_unregister(kmb->kmb_dsi); > + kmb_dsi_host_unregister(); > drm_atomic_helper_shutdown(drm); > + drm_dev_put(drm); > return 0; > } > > @@ -519,7 +520,7 @@ static int kmb_probe(struct platform_device *pdev) > if (IS_ERR(kmb->kmb_dsi)) { > drm_err(&kmb->drm, "failed to initialize DSI\n"); > ret = PTR_ERR(kmb->kmb_dsi); > - goto err_free1; > + goto err_free2; Don't use numberred labels. The label names should say what the goto does just like a function name says what calling the function does. The existing label names in this function mostly use "Come From" label style which is not useful either. When you're writing probe function keep track in your head of the most recent successful allocation and then when an error occurs that's what you have to free. a = alloc(); if (!a) return; <-- nothing to free b = alloc(); if (!b) goto free_a; <-- good name. a is the most recent. c = alloc(); if (!c) goto free_b; return 0; free_b: free(b); free_a: free(a); Then copy and past the error handling and add a free(c) to create the release function: void release(struct foo *p) { free(c); free(b); free(a); } regards, dan carpenter