============================================ WARNING: possible recursive locking detected 6.2.0-rc6-syzkaller-00202-gb963d9d5b943 #0 Not tainted -------------------------------------------- udevd/6631 is trying to acquire lock: ffffffff8c818db8 (trace_printk_lock){-.-.}-{2:2}, at: ____bpf_trace_printk kernel/trace/bpf_trace.c:391 [inline] ffffffff8c818db8 (trace_printk_lock){-.-.}-{2:2}, at: bpf_trace_printk+0xd3/0x170 kernel/trace/bpf_trace.c:377 but task is already holding lock: ffffffff8c818db8 (trace_printk_lock){-.-.}-{2:2}, at: ____bpf_trace_printk kernel/trace/bpf_trace.c:391 [inline] ffffffff8c818db8 (trace_printk_lock){-.-.}-{2:2}, at: bpf_trace_printk+0xd3/0x170 kernel/trace/bpf_trace.c:377 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(trace_printk_lock); lock(trace_printk_lock); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by udevd/6631: #0: ffff888146dec4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xc0/0x770 block/bdev.c:911 #1: ffffffff8c790300 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2262 [inline] #1: ffffffff8c790300 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xbd/0x3d0 kernel/trace/bpf_trace.c:2306 #2: ffffffff8c818db8 (trace_printk_lock){-.-.}-{2:2}, at: ____bpf_trace_printk kernel/trace/bpf_trace.c:391 [inline] #2: ffffffff8c818db8 (trace_printk_lock){-.-.}-{2:2}, at: bpf_trace_printk+0xd3/0x170 kernel/trace/bpf_trace.c:377 #3: ffffffff8c790300 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2262 [inline] #3: ffffffff8c790300 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xbd/0x3d0 kernel/trace/bpf_trace.c:2306 stack backtrace: CPU: 0 PID: 6631 Comm: udevd Not tainted 6.2.0-rc6-syzkaller-00202-gb963d9d5b943 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2990 [inline] check_deadlock kernel/locking/lockdep.c:3033 [inline] validate_chain kernel/locking/lockdep.c:3818 [inline] __lock_acquire.cold+0x116/0x3a7 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162 ____bpf_trace_printk kernel/trace/bpf_trace.c:391 [inline] bpf_trace_printk+0xd3/0x170 kernel/trace/bpf_trace.c:377 bpf_prog_0605f9f479290f07+0x37/0x3b bpf_dispatcher_nop_func include/linux/bpf.h:1082 [inline] __bpf_prog_run include/linux/filter.h:593 [inline] bpf_prog_run include/linux/filter.h:607 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2267 [inline] bpf_trace_run2+0x225/0x3d0 kernel/trace/bpf_trace.c:2306 __bpf_trace_contention_begin+0xb9/0xf0 include/trace/events/lock.h:95 __traceiter_contention_begin+0x5a/0xa0 include/trace/events/lock.h:95 trace_contention_begin.constprop.0+0x143/0x240 include/trace/events/lock.h:95 __pv_queued_spin_lock_slowpath+0x107/0xb50 kernel/locking/qspinlock.c:405 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x204/0x2b0 kernel/locking/spinlock_debug.c:115 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0x45/0x60 kernel/locking/spinlock.c:162 ____bpf_trace_printk kernel/trace/bpf_trace.c:391 [inline] bpf_trace_printk+0xd3/0x170 kernel/trace/bpf_trace.c:377 bpf_prog_0605f9f479290f07+0x37/0x3b bpf_dispatcher_nop_func include/linux/bpf.h:1082 [inline] __bpf_prog_run include/linux/filter.h:593 [inline] bpf_prog_run include/linux/filter.h:607 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2267 [inline] bpf_trace_run2+0x225/0x3d0 kernel/trace/bpf_trace.c:2306 __bpf_trace_contention_begin+0xb9/0xf0 include/trace/events/lock.h:95 __traceiter_contention_begin+0x5a/0xa0 include/trace/events/lock.h:95 trace_contention_begin+0x129/0x1e0 include/trace/events/lock.h:95 __mutex_lock_common kernel/locking/mutex.c:605 [inline] __mutex_lock+0x13c/0x1360 kernel/locking/mutex.c:747 blkdev_put+0xc0/0x770 block/bdev.c:911 blkdev_close+0x68/0x80 block/fops.c:492 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0x16f/0x270 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x23c/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f1555d25fc3 Code: 48 ff ff ff b8 ff ff ff ff e9 3e ff ff ff 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 RSP: 002b:00007ffd4292d9c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007f15560d96a8 RCX: 00007f1555d25fc3 RDX: 00007f1555df5a60 RSI: 0000000000000000 RDI: 0000000000000009 RBP: 000055be476c8500 R08: 0000000000000007 R09: 000055be476ce830 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 000055be476ce830 R14: 0000000000000000 R15: 0000000000000000