From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Capella Subject: [PATCH v2 2/3] Fix hibernation restore hang in freeze_processes Date: Mon, 24 Feb 2014 16:27:38 -0800 Message-ID: <1393288059-18174-3-git-send-email-sebastian.capella@linaro.org> References: <1393288059-18174-1-git-send-email-sebastian.capella@linaro.org> Return-path: Received: from mail-pb0-f49.google.com ([209.85.160.49]:49892 "EHLO mail-pb0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752905AbaBYA1x (ORCPT ); Mon, 24 Feb 2014 19:27:53 -0500 Received: by mail-pb0-f49.google.com with SMTP id jt11so1910878pbb.8 for ; Mon, 24 Feb 2014 16:27:53 -0800 (PST) In-Reply-To: <1393288059-18174-1-git-send-email-sebastian.capella@linaro.org> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linaro-kernel@lists.linaro.org, linux-arm-kernel@lists.infradead.org Cc: Sebastian Capella , Russ Dill , Greg Kroah-Hartman During restore, pm_notifier chain are called with PM_RESTORE_PREPARE. The firmware_class driver handler fw_pm_notify does not have a handler for this. As a result, it keeps a reader on the kmod.c umhelper_sem. During freeze_processes, the call to __usermodehelper_disable tries to take a write lock on this semaphore and hangs waiting. Signed-off-by: Sebastian Capella Acked-by: Ming Lei Cc: Russ Dill Cc: Greg Kroah-Hartman --- drivers/base/firmware_class.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index eb8fb94..e2b51f8 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -1541,6 +1541,7 @@ static int fw_pm_notify(struct notifier_block *notify_block, switch (mode) { case PM_HIBERNATION_PREPARE: case PM_SUSPEND_PREPARE: + case PM_RESTORE_PREPARE: kill_requests_without_uevent(); device_cache_fw_images(); break; -- 1.7.9.5