bisecting fixing commit since 18445bf405cb331117bc98427b1ba6f12418ad17 building syzkaller on 94b457068cf474d9fcbfc5ca4cdb71b346166187 testing commit 18445bf405cb331117bc98427b1ba6f12418ad17 with gcc (GCC) 8.1.0 kernel signature: f6c301a0caadc3367a677937a6ecd1b5817d42c4cc9b5916a4e6b8eae912153d run #0: crashed: inconsistent lock state in sco_sock_timeout run #1: crashed: inconsistent lock state in sco_sock_timeout run #2: crashed: inconsistent lock state in sco_conn_del run #3: crashed: inconsistent lock state in sco_conn_del run #4: crashed: inconsistent lock state in sco_conn_del run #5: crashed: inconsistent lock state in sco_conn_del run #6: crashed: inconsistent lock state in sco_conn_del run #7: crashed: inconsistent lock state in sco_conn_del run #8: crashed: inconsistent lock state in sco_conn_del run #9: crashed: inconsistent lock state in sco_conn_del testing current HEAD 92ab97adeefccf375de7ebaad9d5b75d4125fe8b testing commit 92ab97adeefccf375de7ebaad9d5b75d4125fe8b with gcc (GCC) 8.1.0 kernel signature: 9996f3ffa27c62abd5700b5beafe3422adab964a33a46a63a2e5e502b2a27330 run #0: crashed: inconsistent lock state in sco_sock_timeout run #1: crashed: inconsistent lock state in sco_conn_del run #2: crashed: inconsistent lock state in sco_conn_del run #3: crashed: inconsistent lock state in sco_conn_del run #4: crashed: inconsistent lock state in sco_conn_del run #5: crashed: inconsistent lock state in sco_conn_del run #6: OK run #7: crashed: inconsistent lock state in sco_conn_del run #8: OK run #9: OK revisions tested: 2, total time: 28m27.741992832s (build: 9m24.968213274s, test: 18m32.712071833s) the crash still happens on HEAD commit msg: Merge tag 'sh-for-5.9-part2' of git://git.libc.org/linux-sh crash: inconsistent lock state in sco_conn_del ================================ WARNING: inconsistent lock state 5.9.0-rc5-syzkaller #0 Not tainted -------------------------------- inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. syz-executor014/31622 [HC0[0]:SC0[0]:HE1:SE1] takes: ffff8881089570a0 (slock-AF_BLUETOOTH-BTPROTO_SCO){+.?.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline] ffff8881089570a0 (slock-AF_BLUETOOTH-BTPROTO_SCO){+.?.}-{2:2}, at: sco_conn_del.isra.7+0x73/0x120 net/bluetooth/sco.c:176 {IN-SOFTIRQ-W} state was registered at: lock_acquire+0xd7/0x3e0 kernel/locking/lockdep.c:5006 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] sco_sock_timeout+0x1d/0x80 net/bluetooth/sco.c:83 call_timer_fn+0xa7/0x330 kernel/time/timer.c:1413 expire_timers kernel/time/timer.c:1458 [inline] __run_timers kernel/time/timer.c:1755 [inline] run_timer_softirq+0x20d/0x580 kernel/time/timer.c:1768 __do_softirq+0xee/0x55a kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x73/0x90 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0xea/0x110 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x57/0xe0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 arch_local_irq_enable arch/x86/include/asm/paravirt.h:780 [inline] lookup_bh_lru fs/buffer.c:1312 [inline] __find_get_block+0x13d/0x4e0 fs/buffer.c:1324 sb_find_get_block include/linux/buffer_head.h:338 [inline] recently_deleted fs/ext4/ialloc.c:682 [inline] find_inode_bit.isra.20+0xa1/0x180 fs/ext4/ialloc.c:724 __ext4_new_inode+0x49f/0x1c50 fs/ext4/ialloc.c:927 ext4_symlink+0x15f/0x3e0 fs/ext4/namei.c:3315 vfs_symlink+0xe0/0x170 fs/namei.c:3959 do_symlinkat+0xd8/0xf0 fs/namei.c:3986 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 irq event stamp: 1753 hardirqs last enabled at (1753): [] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (1753): [] _raw_spin_unlock_irq+0x1f/0x50 kernel/locking/spinlock.c:199 hardirqs last disabled at (1752): [] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:126 [inline] hardirqs last disabled at (1752): [] _raw_spin_lock_irq+0x68/0x6e kernel/locking/spinlock.c:167 softirqs last enabled at (0): [] copy_process+0x9a8/0x1d50 kernel/fork.c:2004 softirqs last disabled at (0): [<0000000000000000>] 0x0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(slock-AF_BLUETOOTH-BTPROTO_SCO); lock(slock-AF_BLUETOOTH-BTPROTO_SCO); *** DEADLOCK *** 3 locks held by syz-executor014/31622: #0: ffff888111476f40 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x62/0x500 net/bluetooth/hci_core.c:1720 #1: ffff888111476078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0xf5/0x500 net/bluetooth/hci_core.c:1757 #2: ffffffff84559d88 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1435 [inline] #2: ffffffff84559d88 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0x45/0xc0 net/bluetooth/hci_conn.c:1557 stack backtrace: CPU: 1 PID: 31622 Comm: syz-executor014 Not tainted 5.9.0-rc5-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 valid_state kernel/locking/lockdep.c:3361 [inline] mark_lock_irq kernel/locking/lockdep.c:3560 [inline] mark_lock+0x268/0x2d0 kernel/locking/lockdep.c:4006 mark_usage kernel/locking/lockdep.c:3923 [inline] __lock_acquire+0x3d6/0x16e0 kernel/locking/lockdep.c:4380 lock_acquire+0xd7/0x3e0 kernel/locking/lockdep.c:5006 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] sco_conn_del.isra.7+0x73/0x120 net/bluetooth/sco.c:176 hci_disconn_cfm include/net/bluetooth/hci_core.h:1438 [inline] hci_conn_hash_flush+0x64/0xc0 net/bluetooth/hci_conn.c:1557 hci_dev_do_close+0x1ed/0x500 net/bluetooth/hci_core.c:1770 hci_unregister_dev+0x90/0x290 net/bluetooth/hci_core.c:3790 vhci_release+0x2a/0x60 drivers/bluetooth/hci_vhci.c:340 __fput+0xaa/0x250 fs/file_table.c:281 task_work_run+0x68/0xb0 kernel/task_work.c:141 exit_task_work include/linux/task_work.h:25 [inline] do_exit+0x3e1/0xcc0 kernel/exit.c:806 do_group_exit+0x42/0xb0 kernel/exit.c:903 get_signal+0x176/0xcc0 kernel/signal.c:2757 arch_do_signal+0x2b/0x920 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:159 [inline] exit_to_user_mode_prepare+0x1c1/0x220 kernel/entry/common.c:190 syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:265 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x44a659 Code: Bad RIP value. RSP: 002b:00007f15a89b5db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00000000006e6a08 RCX: 000000000044a659 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006e6a08 RBP: 00000000006e6a00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006e6a0c R13: 00007fff1fd7c4af R14: 00007f15a89b69c0 R15: 0000000000000064