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=-16.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 F0159C432BE for ; Sun, 8 Aug 2021 17:36:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C71AB60E53 for ; Sun, 8 Aug 2021 17:36:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232120AbhHHRgy (ORCPT ); Sun, 8 Aug 2021 13:36:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:35518 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230049AbhHHRgx (ORCPT ); Sun, 8 Aug 2021 13:36:53 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9524760F39; Sun, 8 Aug 2021 17:36:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1628444194; bh=eCIS7XuImgqFajzAIwFebZdpc1ovNlOJQg6aacDGhSA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=YIT4zLpchHT/6Ek4ZhTeEyN/j/ake8hV6fmBRkMFA+3TsEmd7j1yv7xtgd2VkypxG Uwzoh6MlGnNqi2TRud+cd3ZOp43STPNVJOGTFDMW3wJ5yOBKE8OUrnX8FD2IRv8hwp I4yc5nUJf+IZEg3o0lsQYTVGRCJYiDsSFqHMVO1E= Date: Sun, 8 Aug 2021 19:36:31 +0200 From: Greg KH To: Prasad Sodagudi Cc: rjw@rjwysocki.net, len.brown@intel.com, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, pavel@ucw.cz Subject: Re: [PATCH v2] PM: sleep: core: Avoid setting power.must_resume to false Message-ID: References: <1628439027-345496-1-git-send-email-psodagud@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1628439027-345496-1-git-send-email-psodagud@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Aug 08, 2021 at 09:10:27AM -0700, Prasad Sodagudi wrote: > There are variables(power.may_skip_resume and dev->power.must_resume) > and DPM_FLAG_MAY_SKIP_RESUME flags to control the resume of devices after > a system wide suspend transition. > > Setting the DPM_FLAG_MAY_SKIP_RESUME flag means that the driver allows > its "noirq" and "early" resume callbacks to be skipped if the device > can be left in suspend after a system-wide transition into the working > state. PM core determines that the driver's "noirq" and "early" resume > callbacks should be skipped or not with dev_pm_skip_resume() function by > checking power.may_skip_resume variable. > > power.must_resume variable is getting set to false in __device_suspend() > function without checking device's DPM_FLAG_MAY_SKIP_RESUME and > dev->power.usage_count variables. In problematic scenario, where > all the devices in the suspend_late stage are successful and some > device can fail to suspend in suspend_noirq phase. So some devices > successfully suspended in suspend_late stage are not getting chance > to execute __device_suspend_noirq() to set dev->power.must_resume > variable to true and not getting resumed in early_resume phase. > > Add a check for device's DPM_FLAG_MAY_SKIP_RESUME flag before > setting power.must_resume variable in __device_suspend function. > > Fixes: 6e176bf8d461 ("PM: sleep: core: Do not skip callbacks in the resume phase") > Signed-off-by: Prasad Sodagudi > --- > drivers/base/power/main.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c > index d568772..9ee6987 100644 > --- a/drivers/base/power/main.c > +++ b/drivers/base/power/main.c > @@ -1642,7 +1642,11 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async) > } > > dev->power.may_skip_resume = true; > - dev->power.must_resume = false; > + if ((atomic_read(&dev->power.usage_count) <= 1) && > + (dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME))) > + dev->power.must_resume = false; > + else > + dev->power.must_resume = true; > > dpm_watchdog_set(&wd, dev); > device_lock(dev); > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project > Hi, This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him a patch that has triggered this response. He used to manually respond to these common problems, but in order to save his sanity (he kept writing the same thing over and over, yet to different people), I was created. Hopefully you will not take offence and will fix the problem in your patch and resubmit it so that it can be accepted into the Linux kernel tree. You are receiving this message because of the following common error(s) as indicated below: - This looks like a new version of a previously submitted patch, but you did not list below the --- line any changes from the previous version. Please read the section entitled "The canonical patch format" in the kernel file, Documentation/SubmittingPatches for what needs to be done here to properly describe this. If you wish to discuss this problem further, or you have questions about how to resolve this issue, please feel free to respond to this email and Greg will reply once he has dug out from the pending patches received from other developers. thanks, greg k-h's patch email bot