From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jiang Liu , David Woodhouse , Joerg Roedel Subject: [PATCH 3.16 013/158] iommu/vt-d: Defer domain removal if device is assigned to a driver Date: Mon, 15 Sep 2014 12:24:12 -0700 Message-Id: <20140915192543.280737055@linuxfoundation.org> In-Reply-To: <20140915192542.872134685@linuxfoundation.org> References: <20140915192542.872134685@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joerg Roedel commit e7f9fa5498d91fcdc63d93007ba43f36b1a30538 upstream. When the BUS_NOTIFY_DEL_DEVICE event is received the device might still be attached to a driver. In this case the domain can't be released as the mappings might still be in use. Defer the domain removal in this case until we receivce the BUS_NOTIFY_UNBOUND_DRIVER event. Cc: Jiang Liu Cc: David Woodhouse Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman --- drivers/iommu/intel-iommu.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -3891,6 +3891,14 @@ static int device_notifier(struct notifi action != BUS_NOTIFY_DEL_DEVICE) return 0; + /* + * If the device is still attached to a device driver we can't + * tear down the domain yet as DMA mappings may still be in use. + * Wait for the BUS_NOTIFY_UNBOUND_DRIVER event to do that. + */ + if (action == BUS_NOTIFY_DEL_DEVICE && dev->driver != NULL) + return 0; + domain = find_domain(dev); if (!domain) return 0;