Hi William, url: https://github.com/0day-ci/linux/commits/William-Breathitt-Gray/Introduce-the-Counter-character-device-interface/20210705-162324 base: 6cbb3aa0f9d5d23221df787cf36f74d3866fdb78 config: parisc-randconfig-m031-20210705 (attached as .config) compiler: hppa-linux-gcc (GCC) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> smatch warnings: drivers/counter/counter-sysfs.c:815 counter_events_queue_size_write() warn: inconsistent returns '&counter->chrdev_lock'. vim +815 drivers/counter/counter-sysfs.c d95f8a2e83a813 William Breathitt Gray 2021-07-05 794 static int counter_events_queue_size_write(struct counter_device *counter, d95f8a2e83a813 William Breathitt Gray 2021-07-05 795 u64 val) d95f8a2e83a813 William Breathitt Gray 2021-07-05 796 { d95f8a2e83a813 William Breathitt Gray 2021-07-05 797 int err; d95f8a2e83a813 William Breathitt Gray 2021-07-05 798 DECLARE_KFIFO_PTR(events, struct counter_event); d95f8a2e83a813 William Breathitt Gray 2021-07-05 799 d95f8a2e83a813 William Breathitt Gray 2021-07-05 800 /* Verify chrdev is not currently being used */ d95f8a2e83a813 William Breathitt Gray 2021-07-05 801 if (!mutex_trylock(&counter->chrdev_lock)) d95f8a2e83a813 William Breathitt Gray 2021-07-05 802 return -EBUSY; d95f8a2e83a813 William Breathitt Gray 2021-07-05 803 d95f8a2e83a813 William Breathitt Gray 2021-07-05 804 /* Allocate new events queue */ d95f8a2e83a813 William Breathitt Gray 2021-07-05 805 err = kfifo_alloc(&events, val, GFP_ATOMIC); d95f8a2e83a813 William Breathitt Gray 2021-07-05 806 if (err) d95f8a2e83a813 William Breathitt Gray 2021-07-05 807 return err; Drop the lock. With a mutex the alloc() doesn't necessarily have to ATOMIC by the way. d95f8a2e83a813 William Breathitt Gray 2021-07-05 808 d95f8a2e83a813 William Breathitt Gray 2021-07-05 809 /* Swap in new events queue */ d95f8a2e83a813 William Breathitt Gray 2021-07-05 810 kfifo_free(&counter->events); d95f8a2e83a813 William Breathitt Gray 2021-07-05 811 counter->events.kfifo = events.kfifo; d95f8a2e83a813 William Breathitt Gray 2021-07-05 812 d95f8a2e83a813 William Breathitt Gray 2021-07-05 813 mutex_unlock(&counter->chrdev_lock); d95f8a2e83a813 William Breathitt Gray 2021-07-05 814 d95f8a2e83a813 William Breathitt Gray 2021-07-05 @815 return 0; d95f8a2e83a813 William Breathitt Gray 2021-07-05 816 } --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
