====================================================== WARNING: possible circular locking dependency detected 6.15.0-syzkaller-13659-g5b032cac6225 #0 Not tainted ------------------------------------------------------ syz.1.4463/18988 is trying to acquire lock: ffff88802ab494d8 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: touch_work_lockdep_map kernel/workqueue.c:3924 [inline] ffff88802ab494d8 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: start_flush_work kernel/workqueue.c:4178 [inline] ffff88802ab494d8 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: __flush_work+0x4d0/0xcc0 kernel/workqueue.c:4210 but task is already holding lock: ffff88802ab48258 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x378/0x5f0 net/smc/af_smc.c:336 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sk_lock-AF_SMC/1){+.+.}-{0:0}: lock_sock_nested+0x41/0xf0 net/core/sock.c:3752 smc_listen_out+0x202/0x4a0 net/smc/af_smc.c:1913 smc_listen_out_connected net/smc/af_smc.c:1933 [inline] smc_listen_work+0x5a3/0x50e0 net/smc/af_smc.c:2455 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 -> #0 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x126f/0x1c90 kernel/locking/lockdep.c:5240 lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828 touch_work_lockdep_map kernel/workqueue.c:3924 [inline] start_flush_work kernel/workqueue.c:4178 [inline] __flush_work+0x4e4/0xcc0 kernel/workqueue.c:4210 __cancel_work_sync+0x10c/0x130 kernel/workqueue.c:4366 smc_clcsock_release+0x5f/0xe0 net/smc/smc_close.c:29 __smc_release+0x5c2/0x880 net/smc/af_smc.c:301 smc_close_non_accepted+0xda/0x200 net/smc/af_smc.c:1844 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline] smc_close_active+0xc3c/0x1070 net/smc/smc_close.c:225 __smc_release+0x634/0x880 net/smc/af_smc.c:277 smc_release+0x1fc/0x5f0 net/smc/af_smc.c:344 __sock_release+0xb3/0x270 net/socket.c:647 sock_close+0x1c/0x30 net/socket.c:1391 __fput+0x402/0xb70 fs/file_table.c:465 task_work_run+0x150/0x240 kernel/task_work.c:227 get_signal+0x1d1/0x26d0 kernel/signal.c:2807 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_SMC/1); lock((work_completion)(&new_smc->smc_listen_work)); lock(sk_lock-AF_SMC/1); lock((work_completion)(&new_smc->smc_listen_work)); *** DEADLOCK *** 3 locks held by syz.1.4463/18988: #0: ffff888054c78208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888054c78208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:646 #1: ffff88802ab48258 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x378/0x5f0 net/smc/af_smc.c:336 #2: ffffffff8e5c4cc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8e5c4cc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8e5c4cc0 (rcu_read_lock){....}-{1:3}, at: start_flush_work kernel/workqueue.c:4152 [inline] #2: ffffffff8e5c4cc0 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xfb/0xcc0 kernel/workqueue.c:4210 stack backtrace: CPU: 1 UID: 0 PID: 18988 Comm: syz.1.4463 Not tainted 6.15.0-syzkaller-13659-g5b032cac6225 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x275/0x350 kernel/locking/lockdep.c:2046 check_noncircular+0x14c/0x170 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x126f/0x1c90 kernel/locking/lockdep.c:5240 lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828 touch_work_lockdep_map kernel/workqueue.c:3924 [inline] start_flush_work kernel/workqueue.c:4178 [inline] __flush_work+0x4e4/0xcc0 kernel/workqueue.c:4210 __cancel_work_sync+0x10c/0x130 kernel/workqueue.c:4366 smc_clcsock_release+0x5f/0xe0 net/smc/smc_close.c:29 __smc_release+0x5c2/0x880 net/smc/af_smc.c:301 smc_close_non_accepted+0xda/0x200 net/smc/af_smc.c:1844 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline] smc_close_active+0xc3c/0x1070 net/smc/smc_close.c:225 __smc_release+0x634/0x880 net/smc/af_smc.c:277 smc_release+0x1fc/0x5f0 net/smc/af_smc.c:344 __sock_release+0xb3/0x270 net/socket.c:647 sock_close+0x1c/0x30 net/socket.c:1391 __fput+0x402/0xb70 fs/file_table.c:465 task_work_run+0x150/0x240 kernel/task_work.c:227 get_signal+0x1d1/0x26d0 kernel/signal.c:2807 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb64a58e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb64b402038 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX: fffffffffffffe00 RBX: 00007fb64a7b5fa0 RCX: 00007fb64a58e929 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007fb64a610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb64a7b5fa0 R15: 00007ffea7849fc8