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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 58070C43381 for ; Thu, 21 Feb 2019 07:59:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 26DF42086A for ; Thu, 21 Feb 2019 07:59:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="bVIn4Wnr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727298AbfBUH7L (ORCPT ); Thu, 21 Feb 2019 02:59:11 -0500 Received: from mail-wm1-f68.google.com ([209.85.128.68]:37492 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725831AbfBUH7K (ORCPT ); Thu, 21 Feb 2019 02:59:10 -0500 Received: by mail-wm1-f68.google.com with SMTP id x10so8846240wmg.2 for ; Wed, 20 Feb 2019 23:59:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=wd5LWqxi3KTL1mk2vfXcGPq8iJCNRzZJVnK0M/1Bo3U=; b=bVIn4WnrPcR4HTYDzRKojaZ50k3GEfJW7Sksmhzc/679sbwDlgI2DA5Gs1UvmPeQwZ ZQJBAQ29bKaDtL4yT6B7KkLO4O4HkVub2imU1j6cLxBviJ3PQ3ZR/vrw7s9aRT727icr l7v7ITADpl/TXytVuSDehgcFhc0OrM7ytHMs6o7GABVjrvSJDZOLo787S58bB5+W87B3 6nCLqR5RdiGg/9Ks+pHvv86fQ6goEN25lPRO8CLii2y+IvG2ogkV5kZFtAQ+HT3e2Qtv kPIDSVsIgnLnBFrFD8hUEMrABLNL41O+qXcM3Ocab8fE5K9WMo0ODNNF2UQRBjS2iiO7 ELGg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=wd5LWqxi3KTL1mk2vfXcGPq8iJCNRzZJVnK0M/1Bo3U=; b=CGI7KYtT6meaGdtyfObCUECzo65OoHuhv+g31XF/EeaRkn19BbWwy55s1rAl2OfH6c xWx61ocOkgAGPNB/8ii0iCmwOI+rdRQog1ThgsNZTSPzfcaCIK9rbSnSXdP2umqXE2iK 3pbAKNHEhvNHeoq/h9VF7cj+FNmucDfPwUA2gEmQGXmLaUgt2QTEQU3JHre78Au0X1eo /8q5lmp+6QER9gu7hfHlnJLlC72QZBx580+Gwdymn0efHQN339WcG/InkdeDLnOU7623 3ny5J+b9Uo2jfnwfwKi0BYxbP6msowkCA+rjmy3fFRSnsSZP8KpCMe4aaWbiSRPkrxs9 EwcQ== X-Gm-Message-State: AHQUAuYafGk/Fj21NLDT0F1H6VML3GGHk2fZJeeyoMF7pDfkO18bap7B 421Ni3HvJBvdXdnRYJG/dpUZ6g== X-Google-Smtp-Source: AHgI3IZbHPzMylUlX8znklRpZt8Js/R70hjxQ5T3DuZ42/aaRjBoP2ALBXGBtxVjwwPJ9do6lNHT3w== X-Received: by 2002:a1c:dc8a:: with SMTP id t132mr10206801wmg.48.1550735948722; Wed, 20 Feb 2019 23:59:08 -0800 (PST) Received: from localhost.localdomain ([2a01:e0a:f:6020:a9b1:5119:7e50:9df]) by smtp.gmail.com with ESMTPSA id o12sm73384517wre.0.2019.02.20.23.59.07 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 20 Feb 2019 23:59:07 -0800 (PST) From: Vincent Guittot To: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, rjw@rjwysocki.net, ulf.hansson@linaro.org Cc: sunzhaosheng@hisilicon.com, Vincent Guittot Subject: [PATCH] PM-runtime: fix deadlock when canceling hrtimer Date: Thu, 21 Feb 2019 08:59:02 +0100 Message-Id: <1550735942-3569-1-git-send-email-vincent.guittot@linaro.org> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When rpm_resume() desactivates the autosuspend timer, it should only try to cancel hrtimer but not wait for the handler to finish because both rpm_resume() and pm_suspend_timer_fn() are taking the power.lock. We can have the deadlock sequence: CPU0 CPU1 rpm_resume() spin_lock_irqsave pm_suspend_timer_fn() spin_lock_irqsave pm_runtime_deactivate_timer() hrtimer_cancel() hrtimer_try_to_cancel() is enough because dev->power.timer_expires is also set to 0. Fixes: 8234f6734c5d ("PM-runtime: Switch autosuspend over to using hrtimers") Reported-by: Sunzhaosheng Sun(Zhaosheng) Signed-off-by: Vincent Guittot --- drivers/base/power/runtime.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 04407d9..78937c4 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -121,7 +121,7 @@ EXPORT_SYMBOL_GPL(pm_runtime_suspended_time); static void pm_runtime_deactivate_timer(struct device *dev) { if (dev->power.timer_expires > 0) { - hrtimer_cancel(&dev->power.suspend_timer); + hrtimer_try_to_cancel(&dev->power.suspend_timer); dev->power.timer_expires = 0; } } -- 2.7.4