From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965560AbeEYJrJ (ORCPT ); Fri, 25 May 2018 05:47:09 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:55153 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965197AbeEYJrH (ORCPT ); Fri, 25 May 2018 05:47:07 -0400 From: Sebastian Andrzej Siewior To: linux-pm@vger.kernel.org Cc: "Rafael J. Wysocki" , Len Brown , Pavel Machek , Thomas Gleixner , bigeasy@linutronix.de, linux-kernel@vger.kernel.org Subject: [PATCH 1/4] PM / suspend: Prevent might sleep splats Date: Fri, 25 May 2018 11:46:45 +0200 Message-Id: <20180525094648.15464-2-bigeasy@linutronix.de> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180525094648.15464-1-bigeasy@linutronix.de> References: <20180525094648.15464-1-bigeasy@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Gleixner timekeeping suspend/resume calls read_persistent_clock() which takes rtc_lock. That results in might sleep warnings because at that point we run with interrupts disabled. We cannot convert rtc_lock to a raw spinlock as that would trigger other might sleep warnings. As a workaround we disable the might sleep warnings by setting system_state to SYSTEM_SUSPEND before calling sysdev_suspend() and restoring it to SYSTEM_RUNNING afer sysdev_resume(). Signed-off-by: Thomas Gleixner [bigeasy: cover s2idle] Signed-off-by: Sebastian Andrzej Siewior --- include/linux/kernel.h | 1 + kernel/power/hibernate.c | 7 +++++++ kernel/power/suspend.c | 6 ++++++ 3 files changed, 14 insertions(+) diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 6a1eb0b0aad9..7aed92624531 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -542,6 +542,7 @@ extern enum system_states { SYSTEM_HALT, SYSTEM_POWER_OFF, SYSTEM_RESTART, + SYSTEM_SUSPEND, } system_state; =20 /* This cannot be an enum because some may be used in assembly source. */ diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 5454cc639a8d..9c85c7822383 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -287,6 +287,8 @@ static int create_image(int platform_mode) =20 local_irq_disable(); =20 + system_state =3D SYSTEM_SUSPEND; + error =3D syscore_suspend(); if (error) { pr_err("Some system devices failed to power down, aborting hibernation\n= "); @@ -317,6 +319,7 @@ static int create_image(int platform_mode) syscore_resume(); =20 Enable_irqs: + system_state =3D SYSTEM_RUNNING; local_irq_enable(); =20 Enable_cpus: @@ -445,6 +448,7 @@ static int resume_target_kernel(bool platform_mode) goto Enable_cpus; =20 local_irq_disable(); + system_state =3D SYSTEM_SUSPEND; =20 error =3D syscore_suspend(); if (error) @@ -478,6 +482,7 @@ static int resume_target_kernel(bool platform_mode) syscore_resume(); =20 Enable_irqs: + system_state =3D SYSTEM_RUNNING; local_irq_enable(); =20 Enable_cpus: @@ -563,6 +568,7 @@ int hibernation_platform_enter(void) goto Enable_cpus; =20 local_irq_disable(); + system_state =3D SYSTEM_SUSPEND; syscore_suspend(); if (pm_wakeup_pending()) { error =3D -EAGAIN; @@ -575,6 +581,7 @@ int hibernation_platform_enter(void) =20 Power_up: syscore_resume(); + system_state =3D SYSTEM_RUNNING; local_irq_enable(); =20 Enable_cpus: diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 4c10be0f4843..9108a99878bf 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -110,6 +110,7 @@ static void s2idle_loop(void) { pm_pr_dbg("suspend-to-idle\n"); =20 + system_state =3D SYSTEM_SUSPEND; for (;;) { int error; =20 @@ -148,6 +149,7 @@ static void s2idle_loop(void) =20 pm_wakeup_clear(false); } + system_state =3D SYSTEM_RUNNING; =20 pm_pr_dbg("resume from suspend-to-idle\n"); } @@ -428,6 +430,8 @@ static int suspend_enter(suspend_state_t state, bool *w= akeup) arch_suspend_disable_irqs(); BUG_ON(!irqs_disabled()); =20 + system_state =3D SYSTEM_SUSPEND; + error =3D syscore_suspend(); if (!error) { *wakeup =3D pm_wakeup_pending(); @@ -443,6 +447,8 @@ static int suspend_enter(suspend_state_t state, bool *w= akeup) syscore_resume(); } =20 + system_state =3D SYSTEM_RUNNING; + arch_suspend_enable_irqs(); BUG_ON(irqs_disabled()); =20 --=20 2.17.0