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 97691C433FE for ; Thu, 10 Nov 2022 01:54:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232245AbiKJByO (ORCPT ); Wed, 9 Nov 2022 20:54:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232024AbiKJByL (ORCPT ); Wed, 9 Nov 2022 20:54:11 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C823A2982C; Wed, 9 Nov 2022 17:54:07 -0800 (PST) Received: from dggpeml500023.china.huawei.com (unknown [172.30.72.55]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4N74cw5wKgz15MW5; Thu, 10 Nov 2022 09:53:52 +0800 (CST) Received: from [10.67.110.112] (10.67.110.112) by dggpeml500023.china.huawei.com (7.185.36.114) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 10 Nov 2022 09:54:05 +0800 Subject: Re: [PATCH] wifi: ath10k: Fix resource leak in ath10k_pci_init() To: Jeff Johnson , , , , , , CC: , , References: <20221108133858.53308-1-xiujianfeng@huawei.com> <4e81efea-23f1-e52c-b0b4-abf445ed5f15@quicinc.com> From: xiujianfeng Message-ID: Date: Thu, 10 Nov 2022 09:54:05 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.9.1 MIME-Version: 1.0 In-Reply-To: <4e81efea-23f1-e52c-b0b4-abf445ed5f15@quicinc.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.67.110.112] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpeml500023.china.huawei.com (7.185.36.114) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, 在 2022/11/10 0:34, Jeff Johnson 写道: > On 11/8/2022 5:38 AM, Xiu Jianfeng wrote: >> When ath10k_ahb_init() fails, it does not unregister ath10k_pci_driver, >> which will cause a resource leak issue, call pci_unregister_driver() in >> the error path to fix this issue. >> >> Fixes: 0b523ced9a3c ("ath10k: add basic skeleton to support ahb") >> Signed-off-by: Xiu Jianfeng >> --- >>   drivers/net/wireless/ath/ath10k/pci.c | 4 +++- >>   1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/net/wireless/ath/ath10k/pci.c >> b/drivers/net/wireless/ath/ath10k/pci.c >> index e56c6a6b1379..22f8f8b20762 100644 >> --- a/drivers/net/wireless/ath/ath10k/pci.c >> +++ b/drivers/net/wireless/ath/ath10k/pci.c >> @@ -3800,8 +3800,10 @@ static int __init ath10k_pci_init(void) >>                  ret); >>       ret = ath10k_ahb_init(); >> -    if (ret) >> +    if (ret) { >>           printk(KERN_ERR "ahb init failed: %d\n", ret); >> +        pci_unregister_driver(&ath10k_pci_driver); >> +    } >>       return ret; >>   } > > imo neither the existing code nor the modified code is correct. > > the driver is attempting to register to support two different buses. > > if either of these is successful then ath10k_pci_init() should return 0 > so that hardware attached to the successful bus can be probed and > supported. > > only if both of these are unsuccessful should ath10k_pci_init() return > an errno. > > so I suggest >     int ret1, ret2; > >     ret1 = pci_register_driver(&ath10k_pci_driver); >     if (ret1) >         printk(KERN_ERR "failed to register ath10k pci driver: %d\n", >                ret1); > >     ret2 = ath10k_ahb_init(); >     if (ret2) >         printk(KERN_ERR "ahb init failed: %d\n", ret2); > >     if (ret1 && ret2) >         return ret1; > >     /* registered to at least one bus */ >     return 0; > } Thanks, this is better. however, if pci_register_driver() returns 0 while ath10k_ahb_init() returns error, it's better to unregister the first bus, here is my another proposal: int ret; ret = pci_register_driver(&ath10k_pci_driver); if (ret) { printk(KERN_ERR "failed to register ath10k pci driver: %d\n", ret); return ret; } ret = ath10k_ahb_init(); if (ret) { printk(KERN_ERR "ahb init failed: %d\n", ret); pci_unregister_driver(&ath10k_pci_driver); return ret; } return 0; If you agree, I will send v2 with this. > > .