3.16-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Joerg Roedel <jroe...@suse.de>

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 <jiang....@linux.intel.com>
Cc: David Woodhouse <dw...@infradead.org>
Signed-off-by: Joerg Roedel <jroe...@suse.de>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 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;


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to