[PATCH] driver core: free devres in device_release

[Ming Lei]

From: Ming Lei <tom.leiming@xxxxxxxxx>

device_del can happen anytime, so once it happens,
the devres of the device will be freed inside device_del, but
drivers can't know it has been deleted and may still add
resources into the device, so memory leak is caused.

This patch moves the devres_release_all to fix the problem.

Signed-off-by: Ming Lei <tom.leiming@xxxxxxxxx>
---
 drivers/base/core.c |   18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/base/core.c b/drivers/base/core.c
index f338037..c8fe4a5 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -184,6 +184,17 @@ static void device_release(struct kobject *kobj)
 	struct device *dev = kobj_to_dev(kobj);
 	struct device_private *p = dev->p;
 
+	/*
+	 * Some platform devices are driven without driver attached
+	 * and managed resources may have been acquired.  Make sure
+	 * all resources are released.
+	 *
+	 * Drivers still can add resources into device after device
+	 * is deleted but alive, so release devres here to avoid
+	 * possible memory leak.
+	 */
+	devres_release_all(dev);
+
 	if (dev->release)
 		dev->release(dev);
 	else if (dev->type && dev->type->release)
@@ -1196,13 +1207,6 @@ void device_del(struct device *dev)
 	bus_remove_device(dev);
 	driver_deferred_probe_del(dev);
 
-	/*
-	 * Some platform devices are driven without driver attached
-	 * and managed resources may have been acquired.  Make sure
-	 * all resources are released.
-	 */
-	devres_release_all(dev);
-
 	/* Notify the platform of the removal, in case they
 	 * need to do anything...
 	 */
-- 
1.7.9.5

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