From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 20E72374CE for ; Tue, 26 Sep 2023 20:26:33 +0000 (UTC) Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E04C121; Tue, 26 Sep 2023 13:26:31 -0700 (PDT) Received: from pps.filterd (m0279871.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 38QJuTNp019157; Tue, 26 Sep 2023 20:24:45 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=message-id : date : mime-version : subject : from : to : cc : references : in-reply-to : content-type : content-transfer-encoding; s=qcppdkim1; bh=NeZCTm8fleHhjmveVpb/txWwGib1sWk+NfoC/HiRkw0=; b=hEcqh0dWX1SS8p5PZoUvJMZBcj3lGYkcY5uxIrDw7n/BKmsaH5RIogo3N6k8UaOEo29K 7wKEMqdpGSEonaflAHQCEStvwfwVKl7Hi/zk74Qe8RvUy7AepJ0A/SnJug2gZrwIRXbe dU2a2dkHwFDAiEZkOcK0Okck9mkYhUtQDIfcpcSXypOvbjSbG2PdOglMDIixq5ufgT+o 6tSCXsbGXgS91W748PIWraA5h3LJnnKRNX/C4YctTCg1MxyB0PImuFZ46ma0dybVtaNU bpBPESWxBxOualFLaKmGpehCSddAdA2xwlTz9MAiYbQqmU5GmNi35Kl3pqxHdw0epHYu 8A== Received: from nalasppmta03.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3tbexgk417-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 26 Sep 2023 20:24:44 +0000 Received: from nalasex01a.na.qualcomm.com (nalasex01a.na.qualcomm.com [10.47.209.196]) by NALASPPMTA03.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 38QKOhTu006928 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 26 Sep 2023 20:24:43 GMT Received: from [10.216.25.31] (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.36; Tue, 26 Sep 2023 13:24:39 -0700 Message-ID: Date: Wed, 27 Sep 2023 01:54:34 +0530 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4] usb: gadget: udc: Handle gadget_connect failure during bind operation From: Krishna Kurapati PSSNV To: Alan Stern CC: Greg Kroah-Hartman , Francesco Dolcini , Badhri Jagan Sridharan , Michael Grzeschik , Ivan Orlov , , , , , References: <20230926193708.22405-1-quic_kriskura@quicinc.com> <2178cf29-5e5c-4ed6-8d1c-916bc7036589@rowland.harvard.edu> <62083b55-0b78-4ebc-ab78-1c1d99f92507@quicinc.com> Content-Language: en-US In-Reply-To: <62083b55-0b78-4ebc-ab78-1c1d99f92507@quicinc.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01a.na.qualcomm.com (10.47.209.196) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: X9VDBCtd15zBvd5hHlkyV8jIbmjBsrJY X-Proofpoint-GUID: X9VDBCtd15zBvd5hHlkyV8jIbmjBsrJY X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-09-26_14,2023-09-26_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 phishscore=0 spamscore=0 suspectscore=0 impostorscore=0 mlxlogscore=993 adultscore=0 clxscore=1015 bulkscore=0 mlxscore=0 malwarescore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2309180000 definitions=main-2309260174 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On 9/27/2023 1:36 AM, Krishna Kurapati PSSNV wrote: >>>   drivers/usb/gadget/udc/core.c | 23 +++++++++++++++++++---- >>>   1 file changed, 19 insertions(+), 4 deletions(-) >>> >>>   static void vbus_event_work(struct work_struct *work) >>> @@ -1604,12 +1608,23 @@ static int gadget_bind_driver(struct device >>> *dev) >>>       } >>>       usb_gadget_enable_async_callbacks(udc); >>>       udc->allow_connect = true; >>> -    usb_udc_connect_control_locked(udc); >>> +    ret = usb_udc_connect_control_locked(udc); >>> +    if (ret) { >>> +        mutex_unlock(&udc->connect_lock); >>> +        goto err_connect_control; >>> +    } >>> + >>>       mutex_unlock(&udc->connect_lock); >>>       kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE); >>>       return 0; >>> + err_connect_control: >>> +    usb_gadget_disable_async_callbacks(udc); >>> +    if (gadget->irq) >>> +        synchronize_irq(gadget->irq); >>> +    usb_gadget_udc_stop_locked(udc); >> >> Not good -- usb_gadget_udc_stop_locked() expects you to be holding >> udc->connect_lock, but you just dropped the lock!  Also, you never set >> udc->allow_connect back to false. >> >> You should move the mutex_unlock() call from inside the "if" statement >> to down here, and add a line for udc->allow_connect. >> > > Hi Alan, > >  Thanks for the review. Will push v5 addressing the changes. > > Hi Alan, I tried out the following diff: - usb_udc_connect_control_locked(udc); + ret = usb_udc_connect_control_locked(udc); + if (ret) + goto err_connect_control; + mutex_unlock(&udc->connect_lock); kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE); return 0; + err_connect_control: + udc->allow_connect = false; + usb_gadget_disable_async_callbacks(udc); + if (gadget->irq) + synchronize_irq(gadget->irq); + usb_gadget_udc_stop_locked(udc); + mutex_unlock(&udc->connect_lock); + If I clear UDC and fail dwc3 soft reset on purpose, I see UDC_store failing: #echo a600000.usb > /sys/kernel/config/usb_gadget/g1/UDC [ 127.394087] dwc3 a600000.usb: request 000000003f43f907 was not queued to ep0out [ 127.401637] udc a600000.usb: failed to start g1: -110 [ 127.406841] configfs-gadget.g1: probe of gadget.0 failed with error -110 [ 127.413809] UDC core: g1: couldn't find an available UDC or it's busy The same output came when I tested v4 as well. Every time soft_reset would fail when I try to write to UDC, UDC_store fails and above log will come up. Can you help confirm if the diff above is proper as I don't see any diff in the logs in v4 and about to push v5. Regards, Krishna,