From a253d1f3e490068fb017855da481762c53f01ab5 Mon Sep 17 00:00:00 2001 From: Alexander Usyskin Date: Mon, 25 Feb 2019 11:09:28 +0200 Subject: [PATCH] mei: bus: move hw module get/put to probe/release commit b5958faa34e2f99f3475ad89c52d98dfea079d33 upstream. 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: Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman --- drivers/misc/mei/bus.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c index fc3872fe7b251..c383322ec2ba0 100644 --- a/drivers/misc/mei/bus.c +++ b/drivers/misc/mei/bus.c @@ -541,17 +541,9 @@ 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); @@ -614,7 +606,6 @@ 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); @@ -725,9 +716,16 @@ 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; @@ -755,6 +753,7 @@ 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; -- 2.50.1