================================ WARNING: inconsistent lock state 5.9.0-rc8-next-20201008-syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. systemd-udevd/10296 [HC0[0]:SC1[1]:HE0:SE0] takes: ffff88802a07f018 (&xa->xa_lock#9){+.?.}-{2:2}, at: xa_destroy+0xaa/0x350 lib/xarray.c:2205 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5419 __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] io_uring_add_task_file fs/io_uring.c:8607 [inline] io_uring_add_task_file+0x207/0x430 fs/io_uring.c:8590 io_uring_get_fd fs/io_uring.c:9116 [inline] io_uring_create fs/io_uring.c:9280 [inline] io_uring_setup+0x2727/0x3660 fs/io_uring.c:9314 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 irq event stamp: 1089 hardirqs last enabled at (1088): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] hardirqs last enabled at (1088): [] _raw_spin_unlock_irqrestore+0x6f/0x90 kernel/locking/spinlock.c:191 hardirqs last disabled at (1089): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (1089): [] _raw_spin_lock_irqsave+0xa9/0xd0 kernel/locking/spinlock.c:159 softirqs last enabled at (856): [] asm_call_irq_on_stack+0xf/0x20 softirqs last disabled at (931): [] asm_call_irq_on_stack+0xf/0x20 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&xa->xa_lock#9); lock(&xa->xa_lock#9); *** DEADLOCK *** 5 locks held by systemd-udevd/10296: #0: ffff8880210e2460 (sb_writers#7){.+.+}-{0:0}, at: sb_start_write include/linux/fs.h:1648 [inline] #0: ffff8880210e2460 (sb_writers#7){.+.+}-{0:0}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:354 #1: ffff888022d3d4d0 (&type->i_mutex_dir_key#5/1 ){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:809 [inline] ){+.+.}-{3:3}, at: do_unlinkat+0x27d/0x660 fs/namei.c:3883 #2: ffff888029254480 (&sb->s_type->i_lock_key){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline] #2: ffff888029254480 (&sb->s_type->i_lock_key){+.+.}-{2:2}, at: d_delete+0x49/0x1c0 fs/dcache.c:2463 #3: ffff8880317a69b8 (&dentry->d_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline] #3: ffff8880317a69b8 (&dentry->d_lock){+.+.}-{2:2}, at: d_delete+0x51/0x1c0 fs/dcache.c:2464 #4: ffffffff8a554c80 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2474 [inline] #4: ffffffff8a554c80 (rcu_callback){....}-{0:0}, at: rcu_core+0x5d8/0x1240 kernel/rcu/tree.c:2718 stack backtrace: CPU: 0 PID: 10296 Comm: systemd-udevd Not tainted 5.9.0-rc8-next-20201008-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+0x198/0x1fb lib/dump_stack.c:118 print_usage_bug kernel/locking/lockdep.c:3715 [inline] valid_state kernel/locking/lockdep.c:3726 [inline] mark_lock_irq kernel/locking/lockdep.c:3929 [inline] mark_lock.cold+0x32/0x74 kernel/locking/lockdep.c:4396 mark_usage kernel/locking/lockdep.c:4281 [inline] __lock_acquire+0x118a/0x56d0 kernel/locking/lockdep.c:4771 lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5419 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x94/0xd0 kernel/locking/spinlock.c:159 xa_destroy+0xaa/0x350 lib/xarray.c:2205 __io_uring_free+0x60/0xc0 fs/io_uring.c:7693 io_uring_free include/linux/io_uring.h:40 [inline] __put_task_struct+0xff/0x3f0 kernel/fork.c:732 put_task_struct include/linux/sched/task.h:111 [inline] delayed_put_task_struct+0x1f6/0x340 kernel/exit.c:172 rcu_do_batch kernel/rcu/tree.c:2484 [inline] rcu_core+0x645/0x1240 kernel/rcu/tree.c:2718 __do_softirq+0x203/0xab6 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9b/0xd0 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+0x235/0x280 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:84 [inline] RIP: 0010:do_raw_spin_lock+0xa9/0x2b0 kernel/locking/spinlock_debug.c:112 Code: 01 00 00 8b 45 04 3d ad 4e ad de 0f 85 77 01 00 00 4c 8d 6d 10 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 <0f> 85 ba 01 00 00 48 8b 55 10 65 48 8b 04 25 c0 fe 01 00 48 39 c2 RSP: 0018:ffffc90004577d18 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: 1ffff920008aefa4 RCX: 0000000000000000 RDX: 1ffff110062f4d36 RSI: 0000000000000001 RDI: ffff8880317a69a4 RBP: ffff8880317a69a0 R08: 0000000000000000 R09: ffffffff8d7329af R10: fffffbfff1ae6535 R11: 0000000000000000 R12: ffff888029254468 R13: ffff8880317a69b0 R14: ffff8880317a6978 R15: ffff8880292543e0 spin_lock include/linux/spinlock.h:354 [inline] d_delete+0x51/0x1c0 fs/dcache.c:2464 vfs_unlink+0x4be/0x600 fs/namei.c:3847 do_unlinkat+0x3b8/0x660 fs/namei.c:3897 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fca7c0150e7 Code: f0 ff ff 73 01 c3 48 8b 0d ae bd 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 bd 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffd4d439628 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fca7c0150e7 RDX: 00302d78743a7365 RSI: 000055fec3ac8d10 RDI: 00007ffd4d439630 RBP: 00007ffd4d439680 R08: 000055fec3ab8100 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000055fec3ac8d10 R13: 000055fec3ad1de0 R14: 0000000000000003 R15: 000000000000000e