Hi Russell King, Here is another bug that's triggered by commit c817a67ecba7c3c2aaa104796d78f160af60920d Author: Russell King Date: Thu Jun 27 15:06:14 2013 +0100 kobject: delayed kobject release: help find buggy drivers [ 50.519381] WARNING: CPU: 0 PID: 1 at lib/debugobjects.c:260 debug_print_object+0x76/0x84() [ 50.519381] ODEBUG: init active (active state 0) object type: timer_list hint: (null) [ 50.519381] Modules linked in: [ 50.519381] CPU: 0 PID: 1 Comm: swapper Not tainted 3.11.0-rc6-next-20130822-07070-g245f086 #1 [ 50.519381] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 50.519381] 40041b68 40041b68 40041b28 41340817 40041b58 41022949 41473af6 40041b84 [ 50.519381] 00000001 41473b33 00000104 411e84d7 411e84d7 40085698 414e1f14 41451647 [ 50.519381] 40041b70 4102298e 00000009 40041b68 41473af6 40041b84 40041ba4 411e84d7 [ 50.519381] Call Trace: [ 50.519381] [<41340817>] dump_stack+0x16/0x18 [ 50.519381] [<41022949>] warn_slowpath_common+0x70/0x87 [ 50.519381] [<411e84d7>] ? debug_print_object+0x76/0x84 [ 50.519381] [<411e84d7>] ? debug_print_object+0x76/0x84 [ 50.519381] [<4102298e>] warn_slowpath_fmt+0x2e/0x30 [ 50.519381] [<411e84d7>] debug_print_object+0x76/0x84 [ 50.519381] [<411e8762>] __debug_object_init+0x27d/0x2bb [ 50.519381] [<411e89c6>] debug_object_init+0x13/0x15 [ 50.519381] [<4102925e>] init_timer_key+0x17/0x64 [ 50.519381] [<411db4a5>] kobject_release+0x50/0x78 [ 50.519381] [<411db51c>] kobject_put+0x4f/0x55 [ 50.519381] [<410ad5bc>] cdev_del+0x23/0x26 [ 50.519381] [<41239fb5>] tty_unregister_device+0x33/0x37 [ 50.519381] [<41247439>] uart_remove_one_port+0xa1/0xee [ 50.519381] [<41249025>] serial8250_register_8250_port+0xc1/0x235 [ 50.519381] [<41249354>] serial8250_probe+0x108/0x16a [ 50.519381] [<4103f19a>] ? sched_clock_cpu+0xd8/0xee [ 50.519381] [<4103f19a>] ? sched_clock_cpu+0xd8/0xee [ 50.519381] [<4125f64a>] platform_drv_probe+0x29/0x4b [ 50.519381] [<4125e242>] driver_probe_device+0x8f/0x194 [ 50.519381] [<4125f76c>] ? platform_match+0x52/0x66 [ 50.519381] [<4125e363>] __device_attach+0x1c/0x2c [ 50.519381] [<4125ccb2>] bus_for_each_drv+0x38/0x6b [ 50.519381] [<4125e17e>] device_attach+0x66/0x83 [ 50.519381] [<4125e347>] ? driver_probe_device+0x194/0x194 [ 50.519381] [<4125d8af>] bus_probe_device+0x25/0x84 [ 50.519381] [<4125c18b>] device_add+0x3e6/0x57b [ 50.519381] [<411e35b9>] ? kvasprintf+0x3b/0x44 [ 50.519381] [<411db956>] ? kobject_set_name_vargs+0x3d/0x4a [ 50.519381] [<4125f4ac>] platform_device_add+0x131/0x195 [ 50.519381] [<4125f97f>] platform_device_register+0x1c/0x1f [ 50.519381] [<41677bb8>] ? setup_early_serial8250_console+0x376/0x376 [ 50.519381] [<41677bc5>] accent_init+0xd/0xf [ 50.519381] [<410003df>] do_one_initcall+0x7e/0x10c [ 50.519381] [<4165b400>] ? do_early_param+0x4f/0x7a [ 50.519381] [<41035bcd>] ? parse_args+0x15d/0x222 [ 50.519381] [<4165ba89>] kernel_init_freeable+0x116/0x1b5 [ 50.519381] [<4165b42b>] ? do_early_param+0x7a/0x7a [ 50.519381] [<4133b3b4>] kernel_init+0xb/0xc3 [ 50.519381] [<413499bb>] ret_from_kernel_thread+0x1b/0x30 [ 50.519381] [<4133b3a9>] ? rest_init+0xb5/0xb5 [ 50.519381] ---[ end trace b81fc16491f309ce ]--- git bisect start 5e8d1acd05687720cbb0b08975eacb7588fdfc42 v3.10 -- git bisect good 8cbd0eefcaf8cc32ded2bf229f0fc379b2ad69f2 # 11:22 60+ Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux git bisect good 60a2b977533c312d271563d955ef7b8e35a6aa38 # 11:35 60+ Merge remote-tracking branch 'infiniband/for-next' git bisect bad 4a225b466e040a70e7d12b159d2a36da1c2ef7dc # 11:41 0- next-20130821/driver-core git bisect good 98246c1ae6f18fe1b710cdff687b6b7077f739c9 # 11:52 60+ Merge remote-tracking branch 'virtio/virtio-next' git bisect good 38136c1f1471c7dcbe889beb790cc4d331e9d3ad # 12:20 60+ Merge remote-tracking branch 'spi/for-next' git bisect good f07762be3b9222a7649cb29a3f5b959204d40446 # 12:29 60+ Merge branch 'x86/asmlinkage' git bisect good 93d6294dfcdff81194086ed9bd6ceca3bc5e5863 # 12:59 60+ Merge remote-tracking branch 'kvm-ppc/kvm-ppc-next' git bisect good c57e8c89b271af4ef914c439effffed53c39434c # 14:10 60+ Merge remote-tracking branch 'leds/for-next' git bisect bad 76f411fb3a62711de7f59e0f4c56456fe356675a # 14:17 0- x86 / cpu topology: remove the stale macro arch_provides_topology_pointers git bisect bad ea1bb7064fd6972ef00a93ba882a2f38450b273e # 14:23 0- video: backlight: convert class code to use dev_groups git bisect good e56341ad380114454119ac043e6d710ddbbb7710 # 14:57 60+ staging: comedi: convert class code to use dev_groups git bisect bad c817a67ecba7c3c2aaa104796d78f160af60920d # 15:09 0- kobject: delayed kobject release: help find buggy drivers git bisect good 7c42721fe0c58a848849b43ff558cf2fb86aa35a # 15:42 60+ char: tile-srom: fix build error git bisect good 7c42721fe0c58a848849b43ff558cf2fb86aa35a # 16:11 180+ char: tile-srom: fix build error git bisect bad 245f08699d5320f021070ed8698ac89ebf2f0670 # 16:11 0- Add linux-next specific files for 20130822 git bisect good cac778c7124d65bf7e3cf27b117a1287f202cac2 # 18:26 180+ Revert "kobject: delayed kobject release: help find buggy drivers" git bisect good 8495e9c4a9616c9d19f23182d0536485902259db # 22:05 180+ Merge tag 'acpi-3.11-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm git bisect bad 245f08699d5320f021070ed8698ac89ebf2f0670 # 22:05 0- Add linux-next specific files for 20130822 Thanks, Fengguang