On Wed, May 20, 2020 at 03:42:17PM +0000, Sverdlin, Alexander (Nokia - DE/Ulm) wrote: > Hello Dinghao, > > On Wed, 2020-05-20 at 21:29 +0800, Dinghao Liu wrote: > > pm_runtime_get_sync() increments the runtime PM usage counter even > > the call returns an error code. Thus a pairing decrement is needed > > on the error handling path to keep the counter balanced. > > I believe, this is the wrong place for such kind of fix. > pm_runtime_get_sync() has obviously a broken semantics with regards to > your observation but no other driver does what you propose. Look again. For example, see what usb_autoresume_device() in drivers/usb/core/driver.c does. You really shouldn't make generalizations such as "no other driver does ..." unless you have read the code for every driver in the kernel. Alan Stern