Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753954Ab2JIH44 (ORCPT ); Tue, 9 Oct 2012 03:56:56 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:54439 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753427Ab2JIH4y (ORCPT ); Tue, 9 Oct 2012 03:56:54 -0400 X-IronPort-AV: E=Sophos;i="4.80,560,1344182400"; d="scan'208";a="5967834" Message-ID: <5073DA15.4040501@cn.fujitsu.com> Date: Tue, 09 Oct 2012 16:02:29 +0800 From: Wen Congyang User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100413 Fedora/3.0.4-2.fc13 Thunderbird/3.0.4 MIME-Version: 1.0 To: Yasuaki Ishimatsu CC: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, lenb@kernel.org, srivatsa.bhat@linux.vnet.ibm.com, toshi.kani@hp.com Subject: Re: [PATCH v3 3/3] acpi : acpi_bus_trim() stops removing devices when failing to remove the device References: <4FFEB35A.6030500@jp.fujitsu.com> <4FFEB4F9.7000906@jp.fujitsu.com> In-Reply-To: <4FFEB4F9.7000906@jp.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/10/09 15:56:45, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/10/09 15:56:45, Serialize complete at 2012/10/09 15:56:45 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5746 Lines: 162 Hi, ishimatsu: At 07/12/2012 07:28 PM, Yasuaki Ishimatsu Wrote: > acpi_bus_trim() stops removing devices, when acpi_bus_remove() return error > number. But acpi_bus_remove() cannot return error number correctly. > acpi_bus_remove() only return -EINVAL, when dev argument is NULL. Thus even if > device cannot be removed correctly, acpi_bus_trim() ignores and continues to > remove devices. acpi_bus_hot_remove_device() uses acpi_bus_trim() for removing > devices. Therefore acpi_bus_hot_remove_device() can send "_EJ0" to firmware, > even if the device is running on the system. In this case, the system cannot > work well. So acpi_bus_trim() should check whether device was removed or not > correctly. The patch adds error check into some functions to remove the device. What is the status about this patch? Vasilis Liaskovitis found a similar bug about the memory hotplug, and this patch can fix this problem: https://lkml.org/lkml/2012/9/26/318 Thanks Wen Congyang > > Signed-off-by: Yasuaki Ishimatsu > > --- > drivers/acpi/scan.c | 15 ++++++++++++--- > drivers/base/dd.c | 22 +++++++++++++++++----- > include/linux/device.h | 2 +- > 3 files changed, 30 insertions(+), 9 deletions(-) > > Index: linux-3.5-rc6/drivers/acpi/scan.c > =================================================================== > --- linux-3.5-rc6.orig/drivers/acpi/scan.c 2012-07-12 20:11:37.316443808 +0900 > +++ linux-3.5-rc6/drivers/acpi/scan.c 2012-07-12 20:17:17.927185231 +0900 > @@ -425,12 +425,17 @@ static int acpi_device_remove(struct dev > { > struct acpi_device *acpi_dev = to_acpi_device(dev); > struct acpi_driver *acpi_drv = acpi_dev->driver; > + int ret; > > if (acpi_drv) { > if (acpi_drv->ops.notify) > acpi_device_remove_notify_handler(acpi_dev); > - if (acpi_drv->ops.remove) > - acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type); > + if (acpi_drv->ops.remove) { > + ret = acpi_drv->ops.remove(acpi_dev, > + acpi_dev->removal_type); > + if (ret) > + return ret; > + } > } > acpi_dev->driver = NULL; > acpi_dev->driver_data = NULL; > @@ -1208,11 +1213,15 @@ static int acpi_device_set_context(struc > > static int acpi_bus_remove(struct acpi_device *dev, int rmdevice) > { > + int ret; > + > if (!dev) > return -EINVAL; > > dev->removal_type = ACPI_BUS_REMOVAL_EJECT; > - device_release_driver(&dev->dev); > + ret = device_release_driver(&dev->dev); > + if (ret) > + return ret; > > if (!rmdevice) > return 0; > Index: linux-3.5-rc6/drivers/base/dd.c > =================================================================== > --- linux-3.5-rc6.orig/drivers/base/dd.c 2012-07-12 20:11:37.316443808 +0900 > +++ linux-3.5-rc6/drivers/base/dd.c 2012-07-12 20:17:17.928185218 +0900 > @@ -464,9 +464,10 @@ EXPORT_SYMBOL_GPL(driver_attach); > * __device_release_driver() must be called with @dev lock held. > * When called for a USB interface, @dev->parent lock must be held as well. > */ > -static void __device_release_driver(struct device *dev) > +static int __device_release_driver(struct device *dev) > { > struct device_driver *drv; > + int ret; > > drv = dev->driver; > if (drv) { > @@ -482,9 +483,11 @@ static void __device_release_driver(stru > pm_runtime_put_sync(dev); > > if (dev->bus && dev->bus->remove) > - dev->bus->remove(dev); > + ret = dev->bus->remove(dev); > else if (drv->remove) > - drv->remove(dev); > + ret = drv->remove(dev); > + if (ret) > + goto rollback; > devres_release_all(dev); > dev->driver = NULL; > klist_remove(&dev->p->knode_driver); > @@ -494,6 +497,12 @@ static void __device_release_driver(stru > dev); > > } > + > + return ret; > + > +rollback: > + driver_sysfs_add(dev); > + return ret; > } > > /** > @@ -503,16 +512,19 @@ static void __device_release_driver(stru > * Manually detach device from driver. > * When called for a USB interface, @dev->parent lock must be held. > */ > -void device_release_driver(struct device *dev) > +int device_release_driver(struct device *dev) > { > + int ret; > /* > * If anyone calls device_release_driver() recursively from > * within their ->remove callback for the same device, they > * will deadlock right here. > */ > device_lock(dev); > - __device_release_driver(dev); > + ret = __device_release_driver(dev); > device_unlock(dev); > + > + return ret; > } > EXPORT_SYMBOL_GPL(device_release_driver); > > Index: linux-3.5-rc6/include/linux/device.h > =================================================================== > --- linux-3.5-rc6.orig/include/linux/device.h 2012-07-12 20:11:37.317443779 +0900 > +++ linux-3.5-rc6/include/linux/device.h 2012-07-12 20:17:17.936185118 +0900 > @@ -827,7 +827,7 @@ static inline void *dev_get_platdata(con > * for information on use. > */ > extern int __must_check device_bind_driver(struct device *dev); > -extern void device_release_driver(struct device *dev); > +extern int device_release_driver(struct device *dev); > extern int __must_check device_attach(struct device *dev); > extern int __must_check driver_attach(struct device_driver *drv); > extern int __must_check device_reprobe(struct device *dev); > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/