============================================ WARNING: possible recursive locking detected 5.18.0-syzkaller-12154-gd352bd889b6a #0 Not tainted -------------------------------------------- sshd/3605 is trying to acquire lock: ffffffff8be0d6d8 (trace_printk_lock){-.-.}-{2:2}, at: ____bpf_trace_printk kernel/trace/bpf_trace.c:388 [inline] ffffffff8be0d6d8 (trace_printk_lock){-.-.}-{2:2}, at: bpf_trace_printk+0xcf/0x170 kernel/trace/bpf_trace.c:374 but task is already holding lock: ffffffff8be0d6d8 (trace_printk_lock){-.-.}-{2:2}, at: ____bpf_trace_printk kernel/trace/bpf_trace.c:388 [inline] ffffffff8be0d6d8 (trace_printk_lock){-.-.}-{2:2}, at: bpf_trace_printk+0xcf/0x170 kernel/trace/bpf_trace.c:374 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 sshd/3605: #0: ffff8880277ad068 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline] #0: ffff8880277ad068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_read+0x139/0x1100 fs/pipe.c:244 #1: ffffffff8bd86be0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x0/0x340 kernel/trace/./bpf_trace.h:11 #2: ffffffff8be0d6d8 (trace_printk_lock){-.-.}-{2:2}, at: ____bpf_trace_printk kernel/trace/bpf_trace.c:388 [inline] #2: ffffffff8be0d6d8 (trace_printk_lock){-.-.}-{2:2}, at: bpf_trace_printk+0xcf/0x170 kernel/trace/bpf_trace.c:374 #3: ffffffff8bd86be0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x0/0x340 kernel/trace/./bpf_trace.h:11 stack backtrace: CPU: 0 PID: 3605 Comm: sshd Not tainted 5.18.0-syzkaller-12154-gd352bd889b6a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2988 [inline] check_deadlock kernel/locking/lockdep.c:3031 [inline] validate_chain kernel/locking/lockdep.c:3816 [inline] __lock_acquire.cold+0x1f5/0x3b4 kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5630 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 ____bpf_trace_printk kernel/trace/bpf_trace.c:388 [inline] bpf_trace_printk+0xcf/0x170 kernel/trace/bpf_trace.c:374 bpf_prog_0605f9f479290f07+0x2f/0x33 bpf_dispatcher_nop_func include/linux/bpf.h:869 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2046 [inline] bpf_trace_run2+0x110/0x340 kernel/trace/bpf_trace.c:2083 __bpf_trace_contention_begin+0xb5/0xf0 include/trace/events/lock.h:95 trace_contention_begin.constprop.0+0xda/0x1b0 include/trace/events/lock.h:95 __pv_queued_spin_lock_slowpath+0x103/0xb50 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+0x200/0x2a0 kernel/locking/spinlock_debug.c:115 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0x41/0x50 kernel/locking/spinlock.c:162 ____bpf_trace_printk kernel/trace/bpf_trace.c:388 [inline] bpf_trace_printk+0xcf/0x170 kernel/trace/bpf_trace.c:374 bpf_prog_0605f9f479290f07+0x2f/0x33 bpf_dispatcher_nop_func include/linux/bpf.h:869 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2046 [inline] bpf_trace_run2+0x110/0x340 kernel/trace/bpf_trace.c:2083 __bpf_trace_contention_begin+0xb5/0xf0 include/trace/events/lock.h:95 trace_contention_begin+0xc0/0x150 include/trace/events/lock.h:95 __mutex_lock_common kernel/locking/mutex.c:605 [inline] __mutex_lock+0x13c/0x1350 kernel/locking/mutex.c:747 __pipe_lock fs/pipe.c:103 [inline] pipe_read+0x139/0x1100 fs/pipe.c:244 call_read_iter include/linux/fs.h:2054 [inline] new_sync_read+0x4f9/0x5f0 fs/read_write.c:401 vfs_read+0x492/0x5d0 fs/read_write.c:482 ksys_read+0x1e8/0x250 fs/read_write.c:620 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7f3fa53258fe Code: c0 e9 e6 fe ff ff 50 48 8d 3d 0e c7 09 00 e8 c9 cf 01 00 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 66 0f 1f 84 00 00 00 00 00 48 83 ec 28 RSP: 002b:00007fff40e3ae68 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3fa53258fe RDX: 0000000000004000 RSI: 00007fff40e3ae78 RDI: 0000000000000009 RBP: 000055a9dd896190 R08: 000055a9dd8a16d0 R09: 00007fff40f92080 R10: 00007fff40f920f0 R11: 0000000000000246 R12: 0000000000000031 R13: 000055a9dd8a5f40 R14: 00007fff40e3ae78 R15: 000055a9dd898370