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 X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C16B0C54FC9 for ; Tue, 21 Apr 2020 11:15:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AACDF2077D for ; Tue, 21 Apr 2020 11:15:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728592AbgDULPT (ORCPT ); Tue, 21 Apr 2020 07:15:19 -0400 Received: from foss.arm.com ([217.140.110.172]:33308 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726018AbgDULPS (ORCPT ); Tue, 21 Apr 2020 07:15:18 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A0F0C1FB; Tue, 21 Apr 2020 04:15:17 -0700 (PDT) Received: from e107158-lin.cambridge.arm.com (e107158-lin.cambridge.arm.com [10.1.195.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9217C3F73D; Tue, 21 Apr 2020 04:15:16 -0700 (PDT) Date: Tue, 21 Apr 2020 12:15:14 +0100 From: Qais Yousef To: Alan Stern Cc: "Rafael J. Wysocki" , Oliver Neukum , Greg Kroah-Hartman , USB list , Linux-pm mailing list , Kernel development list Subject: Re: lockdep warning in urb.c:363 usb_submit_urb Message-ID: <20200421111513.fy3oqebij6fnvbnc@e107158-lin.cambridge.arm.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20171215 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/20/20 16:26, Alan Stern wrote: > On Wed, 25 Mar 2020, Alan Stern wrote: > > > On Wed, 25 Mar 2020, Qais Yousef wrote: > > > > > Thanks for all the hints Alan. > > > > > > I think I figured it out, the below patch seems to fix it for me. Looking > > > at other drivers resume functions it seems we're missing the > > > pm_runtime_disable()->set_active()->enable() dance. Doing that fixes the > > > warning and the dev_err() in driver/base/power. > > > > Ah, yes. This should have been added years ago; guess I forgot. :-( > > > > > I don't see xhci-plat.c doing that, I wonder if it needs it too. > > > > > > I'm not well versed about the details and the rules here. So my fix could be > > > a hack, though it does seem the right thing to do. > > > > > > I wonder why the power core doesn't handle this transparently.. > > > > Initially, we didn't want the PM core to do this automatically because > > we thought some devices might want to remain runtime-suspended > > following a system resume, and only the device driver would know what > > to do. > > Qais: > > So it looks like the discussion with Rafael will lead to changes in the > PM core, but they won't go into the -stable kernels, and they won't > directly fix the problem here. > > In the meantime, why don't you write up your patch below and submit it > properly? Even better, create similar patches for ehci-platform.c and > xhci-plat.c and submit them too. Sure. Thanks -- Qais Yousef > > Alan Stern > > > > diff --git a/drivers/usb/host/ohci-platform.c b/drivers/usb/host/ohci-platform.c > > > index 7addfc2cbadc..eb92c8092fae 100644 > > > --- a/drivers/usb/host/ohci-platform.c > > > +++ b/drivers/usb/host/ohci-platform.c > > > @@ -299,6 +299,10 @@ static int ohci_platform_resume(struct device *dev) > > > } > > > > > > ohci_resume(hcd, false); > > > + > > > + pm_runtime_disable(dev); > > > + pm_runtime_set_active(dev); > > > + pm_runtime_enable(dev); > > > return 0; > > > } > > > #endif /* CONFIG_PM_SLEEP */ > > > > > > > > > Thanks > > > > > > -- > > > Qais Yousef > > > > > > >