From patchwork Mon Aug 19 23:47:57 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 268324 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 76B082C0102 for ; Tue, 20 Aug 2013 09:37:39 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751332Ab3HSXhZ (ORCPT ); Mon, 19 Aug 2013 19:37:25 -0400 Received: from hydra.sisk.pl ([212.160.235.94]:50427 "EHLO hydra.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751241Ab3HSXhY (ORCPT ); Mon, 19 Aug 2013 19:37:24 -0400 Received: from vostro.rjw.lan (cms123.neoplus.adsl.tpnet.pl [83.31.146.123]) by hydra.sisk.pl (Postfix) with ESMTPSA id 0D052E0F19; Tue, 20 Aug 2013 01:32:00 +0200 (CEST) From: "Rafael J. Wysocki" To: ACPI Devel Maling List Cc: LKML , Linux PCI , Linux PM list , Bjorn Helgaas , Toshi Kani , Mika Westerberg Subject: [PATCH] ACPI / PM: Hold acpi_scan_lock over system PM transitions Date: Tue, 20 Aug 2013 01:47:57 +0200 Message-ID: <2852781.TfChGuuEkJ@vostro.rjw.lan> User-Agent: KMail/4.9.5 (Linux/3.11.0-rc5+; KDE/4.9.5; x86_64; ; ) MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Rafael J. Wysocki Bad things happen if ACPI hotplug events are handled during system PM transitions, especially if devices are removed as a result. To prevent those bad things from happening, acquire acpi_scan_lock when a transition is started and release it when that transition is complete or has been aborted. This fixes resume lockup on my test-bed Acer Aspire S5 that happens when Thunderbolt devices are disconnected from the machine while suspended. Signed-off-by: Rafael J. Wysocki Acked-by: Toshi Kani --- Applies on top of the linux-next branch of the linux-pm.git tree. Thanks, Rafael --- drivers/acpi/sleep.c | 39 ++++++++++++++++++++++++--------------- 1 file changed, 24 insertions(+), 15 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Index: linux-pm/drivers/acpi/sleep.c =================================================================== --- linux-pm.orig/drivers/acpi/sleep.c +++ linux-pm/drivers/acpi/sleep.c @@ -420,10 +420,21 @@ static void acpi_pm_finish(void) } /** - * acpi_pm_end - Finish up suspend sequence. + * acpi_pm_start - Start system PM transition. + */ +static void acpi_pm_start(u32 acpi_state) +{ + acpi_target_sleep_state = acpi_state; + acpi_sleep_tts_switch(acpi_target_sleep_state); + acpi_scan_lock_acquire(); +} + +/** + * acpi_pm_end - Finish up system PM transition. */ static void acpi_pm_end(void) { + acpi_scan_lock_release(); /* * This is necessary in case acpi_pm_finish() is not called during a * failing transition to a sleep state. @@ -451,21 +462,19 @@ static u32 acpi_suspend_states[] = { static int acpi_suspend_begin(suspend_state_t pm_state) { u32 acpi_state = acpi_suspend_states[pm_state]; - int error = 0; + int error; error = (nvs_nosave || nvs_nosave_s3) ? 0 : suspend_nvs_alloc(); if (error) return error; - if (sleep_states[acpi_state]) { - acpi_target_sleep_state = acpi_state; - acpi_sleep_tts_switch(acpi_target_sleep_state); - } else { - printk(KERN_ERR "ACPI does not support this state: %d\n", - pm_state); - error = -ENOSYS; + if (!sleep_states[acpi_state]) { + pr_err("ACPI does not support sleep state S%u\n", acpi_state); + return -ENOSYS; } - return error; + + acpi_pm_start(acpi_state); + return 0; } /** @@ -631,10 +640,8 @@ static int acpi_hibernation_begin(void) int error; error = nvs_nosave ? 0 : suspend_nvs_alloc(); - if (!error) { - acpi_target_sleep_state = ACPI_STATE_S4; - acpi_sleep_tts_switch(acpi_target_sleep_state); - } + if (!error) + acpi_pm_start(ACPI_STATE_S4); return error; } @@ -713,8 +720,10 @@ static int acpi_hibernation_begin_old(vo if (!error) { if (!nvs_nosave) error = suspend_nvs_alloc(); - if (!error) + if (!error) { acpi_target_sleep_state = ACPI_STATE_S4; + acpi_scan_lock_acquire(); + } } return error; }