Sorry, it's my carelessness. In v1 I added pm_runtime_put_autosuspend() after copy_from_user() to fix this problem. Since copy_from_user() is moved to the beginning now, we need not to add PM decrement. Regards, Dinghao > On Fri, May 22, 2020 at 10:59:02AM +0800, Dinghao Liu wrote: > > When copy_from_user() returns an error code, there > > is a runtime PM usage counter imbalance. > > > > Fix this by moving copy_from_user() to the beginning > > of this function. > > > > Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx> > > --- > > drivers/usb/musb/musb_debugfs.c | 10 +++++----- > > 1 file changed, 5 insertions(+), 5 deletions(-) > > What changed from v1? Always show that below the --- line as the > documentation says to. > > thanks, > > greg k-h