Hi Ian, url: https://github.com/0day-ci/linux/commits/Ian-Pilcher/Introduce-block-devi... base: a3fa7a101dcff93791d1b1bdb3affcad1410c8c1 config: i386-randconfig-m021-20210912 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; smatch warnings: drivers/leds/trigger/ledtrig-blkdev.c:410 blkdev_disk_unlink_locked() error: dereferencing freed memory 'disk' vim +/disk +410 drivers/leds/trigger/ledtrig-blkdev.c 66cb682de7e8bd Ian Pilcher 2021-09-09 388 static void blkdev_disk_unlink_locked(struct ledtrig_blkdev_led *const led, 66cb682de7e8bd Ian Pilcher 2021-09-09 389 struct ledtrig_blkdev_link *const link, 66cb682de7e8bd Ian Pilcher 2021-09-09 390 struct ledtrig_blkdev_disk *const disk) 66cb682de7e8bd Ian Pilcher 2021-09-09 391 { 66cb682de7e8bd Ian Pilcher 2021-09-09 392 --ledtrig_blkdev_count; 66cb682de7e8bd Ian Pilcher 2021-09-09 393 66cb682de7e8bd Ian Pilcher 2021-09-09 394 if (ledtrig_blkdev_count == 0) 66cb682de7e8bd Ian Pilcher 2021-09-09 395 WARN_ON(!cancel_delayed_work_sync(&ledtrig_blkdev_work)); 66cb682de7e8bd Ian Pilcher 2021-09-09 396 66cb682de7e8bd Ian Pilcher 2021-09-09 397 sysfs_remove_link(led->dir, disk->gd->disk_name); 66cb682de7e8bd Ian Pilcher 2021-09-09 398 sysfs_remove_link(disk->dir, led->led_dev->name); 66cb682de7e8bd Ian Pilcher 2021-09-09 399 kobject_put(disk->dir); 66cb682de7e8bd Ian Pilcher 2021-09-09 400 66cb682de7e8bd Ian Pilcher 2021-09-09 401 hlist_del(&link->led_disks_node); 66cb682de7e8bd Ian Pilcher 2021-09-09 402 hlist_del(&link->disk_leds_node); 66cb682de7e8bd Ian Pilcher 2021-09-09 403 kfree(link); 66cb682de7e8bd Ian Pilcher 2021-09-09 404 66cb682de7e8bd Ian Pilcher 2021-09-09 405 if (hlist_empty(&disk->leds)) { 66cb682de7e8bd Ian Pilcher 2021-09-09 406 disk->gd->ledtrig = NULL; 66cb682de7e8bd Ian Pilcher 2021-09-09 407 kfree(disk); ^^^^ Freed. 66cb682de7e8bd Ian Pilcher 2021-09-09 408 } 66cb682de7e8bd Ian Pilcher 2021-09-09 409 66cb682de7e8bd Ian Pilcher 2021-09-09 @410 put_disk(disk->gd); ^^^^^^^^ Dereference after free. 66cb682de7e8bd Ian Pilcher 2021-09-09 411 } --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org