4.4-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 389b6699a2aa0b457aa69986e9ddf39f3b4030fd ] Currently, stm_register_device() makes the device visible and then proceeds to initializing spinlocks and other properties, which leaves a window when the device can already be opened but is not yet fully operational. Fix this by reversing the initialization order. Reported-by: Alan Cox <alan.cox@xxxxxxxxx> Signed-off-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Reviewed-by: Laurent Fert <laurent.fert@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/hwtracing/stm/core.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index 0c7f0bae001a..b6cc841de79d 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -664,18 +664,11 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data, stm->dev.parent = parent; stm->dev.release = stm_device_release; - err = kobject_set_name(&stm->dev.kobj, "%s", stm_data->name); - if (err) - goto err_device; - - err = device_add(&stm->dev); - if (err) - goto err_device; - mutex_init(&stm->link_mutex); spin_lock_init(&stm->link_lock); INIT_LIST_HEAD(&stm->link_list); + /* initialize the object before it is accessible via sysfs */ spin_lock_init(&stm->mc_lock); mutex_init(&stm->policy_mutex); stm->sw_nmasters = nmasters; @@ -683,6 +676,14 @@ int stm_register_device(struct device *parent, struct stm_data *stm_data, stm->data = stm_data; stm_data->stm = stm; + err = kobject_set_name(&stm->dev.kobj, "%s", stm_data->name); + if (err) + goto err_device; + + err = device_add(&stm->dev); + if (err) + goto err_device; + return 0; err_device: -- 2.19.1
