bisecting fixing commit since 423b8baf18a8c03f2d6fa99aa447ed0da189bb95 building syzkaller on 96c92ad3aba2e4f72be637e26c7562353f6b9f9e testing commit 423b8baf18a8c03f2d6fa99aa447ed0da189bb95 with gcc (GCC) 8.1.0 kernel signature: 1f4aaf45631b5b61cd36f0f896156c19f1bb8a5131ab1d615bfbfb3f174c4554 run #0: crashed: WARNING: locking bug in finish_task_switch run #1: crashed: WARNING: locking bug in finish_task_switch run #2: crashed: WARNING: locking bug in finish_task_switch run #3: crashed: WARNING: locking bug in finish_task_switch run #4: crashed: WARNING: locking bug in finish_task_switch run #5: crashed: WARNING: locking bug in finish_task_switch run #6: crashed: WARNING: locking bug in finish_task_switch run #7: crashed: KASAN: use-after-free Write in hci_sock_bind run #8: crashed: WARNING: locking bug in finish_task_switch run #9: boot failed: can't ssh into the instance testing current HEAD 60e720931556fc1034d0981460164dcf02697679 testing commit 60e720931556fc1034d0981460164dcf02697679 with gcc (GCC) 8.1.0 kernel signature: 9581cb2d9674cf85285debc7adf5cc5c6869585aaa57ddaed4008b9dfd2482be all runs: crashed: WARNING: locking bug in finish_task_switch revisions tested: 2, total time: 26m19.208582387s (build: 11m4.09131549s, test: 14m26.846877367s) the crash still happens on HEAD commit msg: Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux crash: WARNING: locking bug in finish_task_switch ------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(1) WARNING: CPU: 1 PID: 4497 at kernel/locking/lockdep.c:183 hlock_class kernel/locking/lockdep.c:183 [inline] WARNING: CPU: 1 PID: 4497 at kernel/locking/lockdep.c:183 check_wait_context kernel/locking/lockdep.c:4140 [inline] WARNING: CPU: 1 PID: 4497 at kernel/locking/lockdep.c:183 __lock_acquire+0x75d/0x1660 kernel/locking/lockdep.c:4391 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 4497 Comm: syz-executor.2 Not tainted 5.9.0-rc7-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+0xa3/0xcc lib/dump_stack.c:118 panic+0x135/0x31a kernel/panic.c:231 __warn.cold.13+0x20/0x25 kernel/panic.c:600 report_bug+0xc0/0xf0 lib/bug.c:198 handle_bug+0x35/0x90 arch/x86/kernel/traps.c:234 exc_invalid_op+0x13/0x60 arch/x86/kernel/traps.c:254 asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536 RIP: 0010:hlock_class kernel/locking/lockdep.c:183 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4140 [inline] RIP: 0010:__lock_acquire+0x75d/0x1660 kernel/locking/lockdep.c:4391 Code: 28 85 c0 0f 84 e7 fb ff ff 8b 05 86 1d 40 03 85 c0 0f 85 d9 fb ff ff 48 c7 c6 50 12 e9 83 48 c7 c7 92 0e e4 83 e8 de 39 f9 ff <0f> 0b 31 c0 8b 4c 24 28 e9 70 fb ff ff 8b 85 cc 08 00 00 85 c0 0f RSP: 0018:ffffc90004d2fa38 EFLAGS: 00010082 RAX: 0000000000000000 RBX: ffffffff859ee7a0 RCX: 0000000000000003 RDX: 0000000080000003 RSI: 0000000000000001 RDI: 0000000000000086 RBP: ffff88810b3b61c0 R08: ffffffff85d2a420 R09: 0000000000000016 R10: 0000000000001191 R11: 0000000039343454 R12: ffff88810b3b6aa8 R13: 0000000000000001 R14: 0000000000000004 R15: 0000000000000001 lock_acquire+0xd7/0x400 kernel/locking/lockdep.c:5029 finish_lock_switch kernel/sched/core.c:3516 [inline] finish_task_switch+0x91/0x280 kernel/sched/core.c:3617 context_switch kernel/sched/core.c:3781 [inline] __schedule+0x40c/0x8a0 kernel/sched/core.c:4527 preempt_schedule_irq+0x42/0x90 kernel/sched/core.c:4785 irqentry_exit_cond_resched kernel/entry/common.c:368 [inline] irqentry_exit+0x5a/0x80 kernel/entry/common.c:388 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline] RIP: 0010:lock_acquire+0x10e/0x400 kernel/locking/lockdep.c:5032 Code: 08 00 00 83 e8 01 66 85 c0 41 89 82 e4 08 00 00 0f 85 63 02 00 00 48 83 3d 16 3f 09 03 00 0f 84 67 02 00 00 48 8b 3c 24 57 9d <0f> 1f 44 00 00 48 8b 44 24 38 65 48 33 04 25 28 00 00 00 0f 85 ce RSP: 0018:ffffc90004d2fcd0 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff85a4de20 RDI: 0000000000000286 RBP: 0000000000000000 R08: ffffffff85a4de20 R09: 00000000000000ff R10: ffff88810b3b61c0 R11: 43761da3d04b4f76 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88810b25cd38 R15: 0000000000000000 flush_workqueue+0xa6/0x590 kernel/workqueue.c:2780 hci_dev_open+0x3a/0xa0 net/bluetooth/hci_core.c:1667 hci_sock_bind+0x38c/0x6b0 net/bluetooth/hci_sock.c:1199 __sys_bind+0xc7/0xe0 net/socket.c:1656 __do_sys_bind net/socket.c:1667 [inline] __se_sys_bind net/socket.c:1665 [inline] __x64_sys_bind+0x11/0x20 net/socket.c:1665 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45caa9 Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0d96f6dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000031 RAX: ffffffffffffffda RBX: 00000000004d99c0 RCX: 000000000045caa9 RDX: 0000000000000006 RSI: 0000000020000140 RDI: 0000000000000005 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000002c R14: 00000000004c2f59 R15: 00007f0d96f6e6d4 Shutting down cpus with NMI Kernel Offset: disabled Rebooting in 86400 seconds..