On 06/06/2018 07:44 AM, Arvind Yadav wrote:
Hi Suzuki,
On Wednesday 06 June 2018 03:13 AM, Suzuki K Poulose wrote:
commit 6403587a930c ("coresight: use put_device() instead of kfree()") introduced a memory leak where, if we fail to register the device for coresight_device, we don't free the "coresight_device" object, which was allocated via kzalloc(). Fix this by jumping to the appropriate error path.
put_device() will decrement the last reference and then free the memory by calling dev->release. Internally put_device() -> kobject_put() -> kobject_cleanup() which is responsible to call 'dev -> release' and also free other kobject resources. If you will see the coresight_device_release. There we are releasing all allocated memory. Still if you call kfree() again then it'll be redundancy.
You're right. I think it would be good to have a comment explaining this to prevent this fix popping up in the future :-). I will add it
Thanks Suzuki