mei: bus: move hw module get/put to probe/release (b5958faa) · Commits · 戴 / test

Fix unbalanced module reference counting during internal reset, which prevents the drivers unloading. Tracking mei_me/txe modules on mei client bus via mei_cldev_enable/disable is error prone due to possible internal reset flow, where clients are disconnected underneath. Moving reference counting to probe and release of mei bus client driver solves this issue in simplest way, as each client provides only a single connection to a client bus driver. Cc: <stable@vger.kernel.org> Signed-off-by:

Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by:

Tomas Winkler <tomas.winkler@intel.com> Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/bus.c

+10 −11

Original line number	Diff line number	Diff line
		@@ -540,17 +540,9 @@ int mei_cldev_enable(struct mei_cl_device *cldev)
		goto out;
		}

		if (!mei_cl_bus_module_get(cldev)) {
		dev_err(&cldev->dev, "get hw module failed");
		ret = -ENODEV;
		goto out;
		}

		ret = mei_cl_connect(cl, cldev->me_cl, NULL);
		if (ret < 0) {
		if (ret < 0)
		dev_err(&cldev->dev, "cannot connect\n");
		mei_cl_bus_module_put(cldev);
		}

		out:
		mutex_unlock(&bus->device_lock);
		@@ -613,7 +605,6 @@ int mei_cldev_disable(struct mei_cl_device *cldev)
		if (err < 0)
		dev_err(bus->dev, "Could not disconnect from the ME client\n");

		mei_cl_bus_module_put(cldev);
		out:
		/* Flush queues and remove any pending read */
		mei_cl_flush_queues(cl, NULL);
		@@ -724,9 +715,16 @@ static int mei_cl_device_probe(struct device *dev)
		if (!id)
		return -ENODEV;

		if (!mei_cl_bus_module_get(cldev)) {
		dev_err(&cldev->dev, "get hw module failed");
		return -ENODEV;
		}

		ret = cldrv->probe(cldev, id);
		if (ret)
		if (ret) {
		mei_cl_bus_module_put(cldev);
		return ret;
		}

		__module_get(THIS_MODULE);
		return 0;
		@@ -754,6 +752,7 @@ static int mei_cl_device_remove(struct device *dev)

		mei_cldev_unregister_callbacks(cldev);

		mei_cl_bus_module_put(cldev);
		module_put(THIS_MODULE);
		dev->driver = NULL;
		return ret;

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