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=-11.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 77B10C4338F for ; Tue, 10 Aug 2021 13:54:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6086160C51 for ; Tue, 10 Aug 2021 13:54:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242084AbhHJNzF (ORCPT ); Tue, 10 Aug 2021 09:55:05 -0400 Received: from so254-9.mailgun.net ([198.61.254.9]:60795 "EHLO so254-9.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242060AbhHJNzE (ORCPT ); Tue, 10 Aug 2021 09:55:04 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1628603682; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=k4nrFBYjkENYXFRZoyAl9snMXCad6DKybTDWMgXjTBE=; b=AJdgbISDLK52KgODdJs7/SO97K2MySktw+b3f58PmObb1BuxFFFp4ZesWLocfoMcw9hq+ItM BVSbo7WAcEXvpAGw+B9BvlSHsob7cFwQhQNsjfRqA6fn+9embfNew/jsVVXIAaJR4/ZN+5aR rp2Dirrl/CaJR4LCgLfsxfv2IT4= X-Mailgun-Sending-Ip: 198.61.254.9 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n04.prod.us-east-1.postgun.com with SMTP id 611285137ee6040977480b55 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 10 Aug 2021 13:54:27 GMT Sender: psodagud=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id C8998C4323A; Tue, 10 Aug 2021 13:54:26 +0000 (UTC) Received: from th-lint-038.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: psodagud) by smtp.codeaurora.org (Postfix) with ESMTPSA id 9DE98C4323A; Tue, 10 Aug 2021 13:54:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 9DE98C4323A Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=psodagud@codeaurora.org From: Prasad Sodagudi To: gregkh@linuxfoundation.org, rjw@rjwysocki.net Cc: len.brown@intel.com, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, pavel@ucw.cz, psodagud@codeaurora.org Subject: [PATCH v2] PM: sleep: core: Avoid setting power.must_resume to false Date: Tue, 10 Aug 2021 06:54:17 -0700 Message-Id: <1628603658-261568-1-git-send-email-psodagud@codeaurora.org> X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is regarding suspend/resume(s2idle) scenario of devices and difference between the LTS kernels 5.4 and 5.10 with respect to devices suspend and resume. Observing that devices suspended in suspend_late stage are not getting resumed in resume_early stage. 1) LTS kernel 5.4 kernel do not have this problem but 5.10 kernel shows this problem. 2) 'commit 6e176bf8d461 ("PM: sleep: core: Do not skip callbacks in the resume phase")' is skipping the driver early_resume callbacks. In device_resume_early function dev->power.must_resume is used to skip the resume call back. It looks this function is expecting that, __device_suspend_noirq() would set dev->power.must_resume = true for the devices which does not have DPM_FLAG_MAY_SKIP_RESUME flag set. 3) Problematic scenario is as follows - During the device suspend/resume scenario all the devices in the suspend_late stage are successful and some device can fail to suspend in suspend_noirq(device_suspend_noirq-> __device_suspend_noirq) phase. As a device failed in dpm_noirq_suspend_devices phase, dpm_resume_noirq is getting called to resume devices in dpm_late_early_list in the noirq phase. 4) During the Devices_early_resume stage dpm_resume_early()-->device_resume_early() functions skipping the devices early resume callbacks. 799 if (dev_pm_skip_resume(dev)) 800 goto Skip; 5) Devices suspended in suspend_late stage are not getting resumed in Devices_early_resume stage because of 'commit 6e176bf8d461 ("PM: sleep: core: Do not skip callbacks in the resume phase")' is skipping the driver early_resume callbacks when dev->power.must_resume is false. Changelog: v1 -> v2: - Fixed indentation comments. - Commit text updated to include scenario. Prasad Sodagudi (1): PM: sleep: core: Avoid setting power.must_resume to false drivers/base/power/main.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project