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 E5422EEB562 for ; Fri, 8 Sep 2023 18:59:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243957AbjIHS7r (ORCPT ); Fri, 8 Sep 2023 14:59:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243969AbjIHS7q (ORCPT ); Fri, 8 Sep 2023 14:59:46 -0400 Received: from mx01.omp.ru (mx01.omp.ru [90.154.21.10]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0257F1BF9 for ; Fri, 8 Sep 2023 11:59:17 -0700 (PDT) Received: from [192.168.1.103] (178.176.76.159) by msexch01.omp.ru (10.188.4.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.986.14; Fri, 8 Sep 2023 21:58:28 +0300 Subject: Re: [PATCH v4] usb: host: xhci-plat: fix possible kernel oops while resuming From: Sergey Shtylyov To: Mathias Nyman , Greg Kroah-Hartman , CC: Florian Fainelli References: Organization: Open Mobile Platform Message-ID: <68a29c4e-1135-37e2-2061-2539f0f0a95c@omp.ru> Date: Fri, 8 Sep 2023 21:58:27 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [178.176.76.159] X-ClientProxiedBy: msexch01.omp.ru (10.188.4.12) To msexch01.omp.ru (10.188.4.12) X-KSE-ServerInfo: msexch01.omp.ru, 9 X-KSE-AntiSpam-Interceptor-Info: scan successful X-KSE-AntiSpam-Version: 5.9.59, Database issued on: 09/08/2023 18:44:50 X-KSE-AntiSpam-Status: KAS_STATUS_NOT_DETECTED X-KSE-AntiSpam-Method: none X-KSE-AntiSpam-Rate: 59 X-KSE-AntiSpam-Info: Lua profiles 179760 [Sep 08 2023] X-KSE-AntiSpam-Info: Version: 5.9.59.0 X-KSE-AntiSpam-Info: Envelope from: s.shtylyov@omp.ru X-KSE-AntiSpam-Info: LuaCore: 530 530 ecb1547b3f72d1df4c71c0b60e67ba6b4aea5432 X-KSE-AntiSpam-Info: {rep_avail} X-KSE-AntiSpam-Info: {Tracking_from_domain_doesnt_match_to} X-KSE-AntiSpam-Info: {relay has no DNS name} X-KSE-AntiSpam-Info: {SMTP from is not routable} X-KSE-AntiSpam-Info: {Found in DNSBL: 178.176.76.159 in (user) dbl.spamhaus.org} X-KSE-AntiSpam-Info: 127.0.0.199:7.1.2;omp.ru:7.1.1;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1 X-KSE-AntiSpam-Info: FromAlignment: s X-KSE-AntiSpam-Info: {rdns complete} X-KSE-AntiSpam-Info: {fromrtbl complete} X-KSE-AntiSpam-Info: ApMailHostAddress: 178.176.76.159 X-KSE-AntiSpam-Info: Rate: 59 X-KSE-AntiSpam-Info: Status: not_detected X-KSE-AntiSpam-Info: Method: none X-KSE-AntiSpam-Info: Auth:dmarc=none header.from=omp.ru;spf=none smtp.mailfrom=omp.ru;dkim=none X-KSE-Antiphishing-Info: Clean X-KSE-Antiphishing-ScanningType: Heuristic X-KSE-Antiphishing-Method: None X-KSE-Antiphishing-Bases: 09/08/2023 18:49:00 X-KSE-Antivirus-Interceptor-Info: scan successful X-KSE-Antivirus-Info: Clean, bases: 9/8/2023 4:00:00 PM X-KSE-Attachment-Filter-Triggered-Rules: Clean X-KSE-Attachment-Filter-Triggered-Filters: Clean X-KSE-BulkMessagesFiltering-Scan-Result: InTheLimit Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On 7/11/23 10:18 PM, Sergey Shtylyov wrote: > If this driver enables the xHC clocks while resuming from sleep, it calls > clk_prepare_enable() without checking for errors and blithely goes on to > read/write the xHC's registers -- which, with the xHC not being clocked, > at least on ARM32 usually causes an imprecise external abort exceptions > which cause kernel oops. Currently, the chips for which the driver does > the clock dance on suspend/resume seem to be the Broadcom STB SoCs, based > on ARM32 CPUs, as it seems... > > In order to fix this issue, add the result checks for clk_prepare_enable() > calls in xhci_plat_resume(), add conditional clk_disable_unprepare() calls > on the error path of xhci_plat_resume(); then factor out the common clock > disabling code from the suspend() and resume() driver PM methods into a > separate function to avoid code duplication. > > Found by Linux Verification Center (linuxtesting.org) with the Svace static > analysis tool. > > Fixes: 8bd954c56197 ("usb: host: xhci-plat: suspend and resume clocks") > Signed-off-by: Sergey Shtylyov > > --- > This patch is against the 'usb-linus' branch of Greg KH's 'usb.git' repo... The v4 of the patch was posted almost 2 months ago... What's going on, is Mathias still opn vacations? [...] MBR, Sergey