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 163B1C43215 for ; Fri, 22 Nov 2019 11:19:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E312C2070E for ; Fri, 22 Nov 2019 11:19:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574421541; bh=znLn9LJ2/eO4Ye50gjLxQYVnp33OeM+DWzZHWQSYY7Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=mNaCgbDuMwATY16HZcRxzUc8vW4VGIjNkYG7Bw1P8uzjd8CFKej04hRcUKUYkO89j /dPGI2Pj/Xi9DJACD6pfG0+G2gjHRJOcZS8BWNopHlXl8EmmOR2ubht51KOTYy3orV 9Nhyezf2c0egyCF+0joQgU8eaDh5Ez7s0Y9RjAEY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729864AbfKVKsM (ORCPT ); Fri, 22 Nov 2019 05:48:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:56590 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729403AbfKVKsJ (ORCPT ); Fri, 22 Nov 2019 05:48:09 -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 601ED205C9; Fri, 22 Nov 2019 10:48:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574419688; bh=znLn9LJ2/eO4Ye50gjLxQYVnp33OeM+DWzZHWQSYY7Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pfbpXHbW0n1PaG+L9/0TBGmjb80640V6aMiR+Nuv8n9Dpi+Q9Myh6NdNmC5+y5skZ 4rfWo/hMj+Pr+R08cxo6cfdXjvuLO5fEOZgj4+MHZDpohVreD1OakqhyKBbaF6FxHj Dhjf6iuNXos8RDrqNUyywIU1nVAiG5kNBnmNaCrY= 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 4.9 197/222] ACPI / SBS: Fix rare oops when removing modules Date: Fri, 22 Nov 2019 11:28:57 +0100 Message-Id: <20191122100916.452503754@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191122100830.874290814@linuxfoundation.org> References: <20191122100830.874290814@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 416953a425109..b9fade7a3bcf4 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -1126,6 +1126,7 @@ 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