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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 6C855C2D0E7 for ; Wed, 25 Mar 2020 20:49:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 43F902074D for ; Wed, 25 Mar 2020 20:49:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727487AbgCYUtJ (ORCPT ); Wed, 25 Mar 2020 16:49:09 -0400 Received: from netrider.rowland.org ([192.131.102.5]:49877 "HELO netrider.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1727399AbgCYUtI (ORCPT ); Wed, 25 Mar 2020 16:49:08 -0400 Received: (qmail 11099 invoked by uid 500); 25 Mar 2020 16:49:07 -0400 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 25 Mar 2020 16:49:07 -0400 Date: Wed, 25 Mar 2020 16:49:07 -0400 (EDT) From: Alan Stern X-X-Sender: stern@netrider.rowland.org To: Qais Yousef , "Rafael J. Wysocki" cc: 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 In-Reply-To: <20200325150017.xhabucfo3v6i234o@e107158-lin> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Raphael, now that we have the direct_complete mechanism, can we revisit this? Should the PM core automatically call pm_runtime_set_active() if dev->power.direct_complete isn't set? Perhaps in device_resume_early() prior to the pm_runtime_enable() call? It's possible we discussed this and decided against it at the time when direct_complete was added, but if so I don't remember what was said. 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