4.4-stable review patch. If anyone has any objections, please let me know.
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[ 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@intel.com Signed-off-by: Alexander Shishkin alexander.shishkin@linux.intel.com Reviewed-by: Laurent Fert laurent.fert@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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: