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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,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 6142EC432C3 for ; Fri, 22 Nov 2019 11:10:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 357A92071C for ; Fri, 22 Nov 2019 11:10:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574421009; bh=a09o/6erw4XFpEHbgbqRKQCSfOoCeDDbbaY/XHSBdzU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UOGPh4/ncoUP5URLa+KMtaAV0tyLMN/Za7zS/KR2hQPGgMwdNmaWYQcplsNKBHQ19 mCSPbecKBg7VXO9wsRXz8oCmsvXCtTvq8PrtY1Yxz0n2e4dCQUWw3LySd0TdF6ptz+ mrbaPIffaqyZ0unGaQ4vOZTvvHaIrPVB4BF7W0V4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730770AbfKVLKH (ORCPT ); Fri, 22 Nov 2019 06:10:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:56060 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731302AbfKVLC3 (ORCPT ); Fri, 22 Nov 2019 06:02:29 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BFFED207FC; Fri, 22 Nov 2019 11:02:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574420549; bh=a09o/6erw4XFpEHbgbqRKQCSfOoCeDDbbaY/XHSBdzU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BdG8v2qUylOII/2rdoabh1vJQliV8KrNTXbXZq7lzY/Z3htV+JvXKz5p43dDjBQuD 10I4UYsXoTeoDfyG6EzafjZXvJ6E4TxCTKu4As0n0eUxwyAnDRriEo+U9yA2ds7QUZ 2UU2o6WUTOqOO7cAHw24tz+1q75lsAwSENsKqNRQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Ronald=20Tschal=C3=83=C2=A4r?= , "Rafael J. Wysocki" , Sasha Levin Subject: [PATCH 4.19 144/220] ACPI / SBS: Fix rare oops when removing modules Date: Fri, 22 Nov 2019 11:28:29 +0100 Message-Id: <20191122100923.126452267@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191122100912.732983531@linuxfoundation.org> References: <20191122100912.732983531@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ronald Tschalär [ Upstream commit 757c968c442397f1249bb775a7c8c03842e3e0c7 ] There was a small race when removing the sbshc module where smbus_alarm() had queued acpi_smbus_callback() for deferred execution but it hadn't been run yet, so that when it did run hc had been freed and the module unloaded, resulting in an invalid paging request. A similar race existed when removing the sbs module with regards to acpi_sbs_callback() (which is called from acpi_smbus_callback()). We therefore need to ensure no callbacks are pending or executing before the cleanups are done and the modules are removed. Signed-off-by: Ronald Tschalär Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/acpi/osl.c | 1 + drivers/acpi/sbshc.c | 2 ++ 2 files changed, 3 insertions(+) diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index ed73f6fb0779b..b48874b8e1ea0 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -1132,6 +1132,7 @@ void acpi_os_wait_events_complete(void) flush_workqueue(kacpid_wq); flush_workqueue(kacpi_notify_wq); } +EXPORT_SYMBOL(acpi_os_wait_events_complete); struct acpi_hp_work { struct work_struct work; diff --git a/drivers/acpi/sbshc.c b/drivers/acpi/sbshc.c index 7a3431018e0ab..5008ead4609a4 100644 --- a/drivers/acpi/sbshc.c +++ b/drivers/acpi/sbshc.c @@ -196,6 +196,7 @@ int acpi_smbus_unregister_callback(struct acpi_smb_hc *hc) hc->callback = NULL; hc->context = NULL; mutex_unlock(&hc->lock); + acpi_os_wait_events_complete(); return 0; } @@ -292,6 +293,7 @@ static int acpi_smbus_hc_remove(struct acpi_device *device) hc = acpi_driver_data(device); acpi_ec_remove_query_handler(hc->ec, hc->query_bit); + acpi_os_wait_events_complete(); kfree(hc); device->driver_data = NULL; return 0; -- 2.20.1