bisecting fixing commit since d18b78abc0c6e7d3119367c931c583e02d466495 building syzkaller on 6436ce4bcd8e2c7dcca0b171ac91f51e96d973f8 testing commit d18b78abc0c6e7d3119367c931c583e02d466495 with gcc (GCC) 8.1.0 kernel signature: 6297e388809e9e31e182ed0c6c5677c10dbc69f79ce13d4c3dfba081c9b8c544 run #0: crashed: general protection fault in __queue_work run #1: crashed: general protection fault in __queue_work run #2: crashed: WARNING: ODEBUG bug in bt_host_release run #3: crashed: WARNING: ODEBUG bug in bt_host_release run #4: crashed: WARNING: ODEBUG bug in bt_host_release run #5: crashed: WARNING: ODEBUG bug in bt_host_release run #6: crashed: general protection fault in __queue_work run #7: OK run #8: OK run #9: OK testing current HEAD ad326970d25cc85128cd22d62398751ad072efff testing commit ad326970d25cc85128cd22d62398751ad072efff with gcc (GCC) 8.1.0 kernel signature: 72609b58d71eb82a7728b90b2b8a9fddd33a99d27884c01177696f0ff0119dc9 run #0: crashed: general protection fault in __queue_work run #1: crashed: general protection fault in __queue_work run #2: crashed: WARNING: ODEBUG bug in bt_host_release run #3: crashed: WARNING: ODEBUG bug in bt_host_release run #4: crashed: WARNING: ODEBUG bug in bt_host_release run #5: crashed: WARNING: ODEBUG bug in bt_host_release run #6: crashed: WARNING: ODEBUG bug in bt_host_release run #7: crashed: general protection fault in __queue_work run #8: crashed: WARNING: ODEBUG bug in bt_host_release run #9: OK revisions tested: 2, total time: 38m6.425082622s (build: 17m36.050720992s, test: 19m52.3106248s) the crash still happens on HEAD commit msg: Linux 4.19.152 crash: WARNING: ODEBUG bug in bt_host_release IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready Bluetooth: hci0: command 0x0c1a tx timeout Bluetooth: hci2: command 0x0419 tx timeout ------------[ cut here ]------------ ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x90 kernel/workqueue.c:4943 WARNING: CPU: 0 PID: 16607 at lib/debugobjects.c:328 debug_print_object+0x168/0x210 lib/debugobjects.c:325 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 16607 Comm: syz-executor.5 Not tainted 4.19.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x17c/0x22a lib/dump_stack.c:118 panic+0x1cd/0x375 kernel/panic.c:186 __warn.cold.7+0x1b/0x3e kernel/panic.c:541 report_bug+0x1a4/0x200 lib/bug.c:186 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x200/0x350 arch/x86/kernel/traps.c:296 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038 RIP: 0010:debug_print_object+0x168/0x210 lib/debugobjects.c:325 Code: 67 87 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 92 00 00 00 48 8b 14 dd 80 8a 67 87 4c 89 fe 48 c7 c7 00 80 67 87 e8 7b bf 07 fe <0f> 0b 83 05 9b d6 f2 05 01 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f RSP: 0018:ffff8880a6e27aa8 EFLAGS: 00010086 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000004 RSI: 0000000000000008 RDI: ffffffff8a19da60 RBP: ffff8880a6e27ae8 R08: ffffed10174c3eef R09: ffffed10174c3eee R10: ffffed10174c3eee R11: ffff8880ba61f777 R12: 0000000000000001 R13: ffffffff88598d40 R14: ffffffff8153a8c0 R15: ffffffff876786e0 __debug_check_no_obj_freed lib/debugobjects.c:785 [inline] debug_check_no_obj_freed+0x252/0x428 lib/debugobjects.c:817 kfree+0xbd/0x220 mm/slab.c:3821 bt_host_release+0x10/0x20 net/bluetooth/hci_sysfs.c:86 device_release+0x71/0x1d0 drivers/base/core.c:1061 kobject_cleanup lib/kobject.c:662 [inline] kobject_release lib/kobject.c:691 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put+0x115/0x1f0 lib/kobject.c:708 put_device+0x12/0x20 drivers/base/core.c:2251 hci_free_dev+0x10/0x20 net/bluetooth/hci_core.c:3145 vhci_release+0x73/0xe0 drivers/bluetooth/hci_vhci.c:355 __fput+0x249/0x7f0 fs/file_table.c:278 ____fput+0x9/0x10 fs/file_table.c:309 task_work_run+0x108/0x180 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xa6a/0x2db0 kernel/exit.c:887 do_group_exit+0xf8/0x2c0 kernel/exit.c:990 __do_sys_exit_group kernel/exit.c:1001 [inline] __se_sys_exit_group kernel/exit.c:999 [inline] __x64_sys_exit_group+0x39/0x40 kernel/exit.c:999 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45d4d9 Code: 24 38 64 48 8b 04 25 f8 ff ff ff 48 8b 40 30 48 8b 80 c0 00 00 00 48 89 44 24 30 0f b6 4a 08 88 4c 24 1f 80 f9 00 31 d2 eb 60 <48> 89 54 24 20 48 89 5c 24 28 48 8d 05 ee 4d 04 01 48 89 04 24 48 RSP: 002b:00007ffdc9ac9ab8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045d4d9 RDX: 0000000000416d61 RSI: 00000000016a85f0 RDI: 0000000000000043 RBP: 00000000004c306d R08: 000000000000000b R09: 0000000000000000 R10: 0000000002dc8940 R11: 0000000000000246 R12: 0000000000000007 R13: 00007ffdc9ac9c00 R14: 0000000000066759 R15: 00007ffdc9ac9c10 ======================================================