From owner-svn-src-stable-9@freebsd.org Tue Mar 14 15:57:23 2017 Return-Path: Delivered-To: svn-src-stable-9@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 32A34D0C7CB; Tue, 14 Mar 2017 15:57:23 +0000 (UTC) (envelope-from hselasky@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id E801114D; Tue, 14 Mar 2017 15:57:22 +0000 (UTC) (envelope-from hselasky@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id v2EFvMbT017711; Tue, 14 Mar 2017 15:57:22 GMT (envelope-from hselasky@FreeBSD.org) Received: (from hselasky@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id v2EFvMeR017710; Tue, 14 Mar 2017 15:57:22 GMT (envelope-from hselasky@FreeBSD.org) Message-Id: <201703141557.v2EFvMeR017710@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: hselasky set sender to hselasky@FreeBSD.org using -f From: Hans Petter Selasky Date: Tue, 14 Mar 2017 15:57:22 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org Subject: svn commit: r315265 - stable/9/sys/dev/acpica X-SVN-Group: stable-9 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-stable-9@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SVN commit messages for only the 9-stable src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 14 Mar 2017 15:57:23 -0000 Author: hselasky Date: Tue Mar 14 15:57:21 2017 New Revision: 315265 URL: https://svnweb.freebsd.org/changeset/base/315265 Log: MFC r314328: Fix startup race initialising ACPI CM battery structures on MacBookPro. During acpi_cmbat_attach() the acpi_cmbat_init_battery() notification handler is registered. It has been observed this notification handler can be called instantly, before the attach routine has returned. In the notification handler there is a call to device_is_attached() which returns false. Because the softc is set we know an attach is in progress and the fix is simply to wait and try again in this case. Reviewed by: avg @ Modified: stable/9/sys/dev/acpica/acpi_cmbat.c Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/dev/acpica/acpi_cmbat.c ============================================================================== --- stable/9/sys/dev/acpica/acpi_cmbat.c Tue Mar 14 15:56:19 2017 (r315264) +++ stable/9/sys/dev/acpica/acpi_cmbat.c Tue Mar 14 15:57:21 2017 (r315265) @@ -164,6 +164,16 @@ acpi_cmbat_detach(device_t dev) handle = acpi_get_handle(dev); AcpiRemoveNotifyHandler(handle, ACPI_ALL_NOTIFY, acpi_cmbat_notify_handler); acpi_battery_remove(dev); + + /* + * Force any pending notification handler calls to complete by + * requesting cmbat serialisation while freeing and clearing the + * softc pointer: + */ + ACPI_SERIAL_BEGIN(cmbat); + device_set_softc(dev, NULL); + ACPI_SERIAL_END(cmbat); + return (0); } @@ -436,7 +446,6 @@ acpi_cmbat_init_battery(void *arg) device_t dev; dev = (device_t)arg; - sc = device_get_softc(dev); ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev), "battery initialization start\n"); @@ -446,18 +455,33 @@ acpi_cmbat_init_battery(void *arg) * to wait a while. */ for (retry = 0; retry < ACPI_CMBAT_RETRY_MAX; retry++, AcpiOsSleep(10000)) { - /* batteries on DOCK can be ejected w/ DOCK during retrying */ - if (!device_is_attached(dev)) + /* + * Batteries on DOCK can be ejected w/ DOCK during retrying. + * + * If there is a valid softc pointer the device may be in + * attaching, attached or detaching state. If the state is + * different from attached retry getting the device state + * until it becomes stable. This solves a race if the ACPI + * notification handler is called during attach, because + * device_is_attached() doesn't return non-zero until after + * the attach code has been executed. + */ + ACPI_SERIAL_BEGIN(cmbat); + sc = device_get_softc(dev); + if (sc == NULL) { + ACPI_SERIAL_END(cmbat); return; + } - if (!acpi_BatteryIsPresent(dev)) + if (!acpi_BatteryIsPresent(dev) || !device_is_attached(dev)) { + ACPI_SERIAL_END(cmbat); continue; + } /* * Only query the battery if this is the first try or the specific * type of info is still invalid. */ - ACPI_SERIAL_BEGIN(cmbat); if (retry == 0 || !acpi_battery_bst_valid(&sc->bst)) { timespecclear(&sc->bst_lastupdated); acpi_cmbat_get_bst(dev);