====================================================== WARNING: possible circular locking dependency detected 6.14.0-syzkaller-12508-g92b71befc349 #0 Not tainted ------------------------------------------------------ syz.3.177/6590 is trying to acquire lock: ffff88805bc52050 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] ffff88805bc52050 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] ffff88805bc52050 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: start_flush_work kernel/workqueue.c:4150 [inline] ffff88805bc52050 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: __flush_work+0xee/0xc60 kernel/workqueue.c:4208 but task is already holding lock: ffff88805bc50dd8 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x234/0x540 net/smc/af_smc.c:-1 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_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 lock_sock_nested+0x48/0x100 net/core/sock.c:3697 smc_listen_out+0x11b/0x3e0 net/smc/af_smc.c:1908 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd50 kernel/workqueue.c:3400 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0xa69/0x24e0 kernel/locking/lockdep.c:3909 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 touch_work_lockdep_map kernel/workqueue.c:3922 [inline] start_flush_work kernel/workqueue.c:4176 [inline] __flush_work+0x75b/0xc60 kernel/workqueue.c:4208 __cancel_work_sync+0xbc/0x110 kernel/workqueue.c:4364 smc_clcsock_release+0x62/0xf0 net/smc/smc_close.c:29 __smc_release+0x683/0x800 net/smc/af_smc.c:301 smc_close_non_accepted+0xd8/0x1f0 net/smc/af_smc.c:1839 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline] smc_close_active+0xadb/0xe90 net/smc/smc_close.c:225 __smc_release+0xa0/0x800 net/smc/af_smc.c:277 smc_release+0x2dc/0x540 net/smc/af_smc.c:344 __sock_release net/socket.c:647 [inline] sock_close+0xbc/0x240 net/socket.c:1391 __fput+0x3e9/0x9f0 fs/file_table.c:465 task_work_run+0x251/0x310 kernel/task_work.c:227 get_signal+0x15db/0x1730 kernel/signal.c:2809 arch_do_signal_or_restart+0x98/0x840 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 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.3.177/6590: #0: ffff88805b948208 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff88805b948208 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff88805b948208 (&sb->s_type->i_mutex_key#9){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1391 #1: ffff88805bc50dd8 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x234/0x540 net/smc/af_smc.c:-1 #2: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: start_flush_work kernel/workqueue.c:4150 [inline] #2: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xee/0xc60 kernel/workqueue.c:4208 stack backtrace: CPU: 0 UID: 0 PID: 6590 Comm: syz.3.177 Not tainted 6.14.0-syzkaller-12508-g92b71befc349 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x2e1/0x300 kernel/locking/lockdep.c:2079 check_noncircular+0x142/0x160 kernel/locking/lockdep.c:2211 check_prev_add kernel/locking/lockdep.c:3166 [inline] check_prevs_add kernel/locking/lockdep.c:3285 [inline] validate_chain+0xa69/0x24e0 kernel/locking/lockdep.c:3909 __lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235 lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866 touch_work_lockdep_map kernel/workqueue.c:3922 [inline] start_flush_work kernel/workqueue.c:4176 [inline] __flush_work+0x75b/0xc60 kernel/workqueue.c:4208 __cancel_work_sync+0xbc/0x110 kernel/workqueue.c:4364 smc_clcsock_release+0x62/0xf0 net/smc/smc_close.c:29 __smc_release+0x683/0x800 net/smc/af_smc.c:301 smc_close_non_accepted+0xd8/0x1f0 net/smc/af_smc.c:1839 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline] smc_close_active+0xadb/0xe90 net/smc/smc_close.c:225 __smc_release+0xa0/0x800 net/smc/af_smc.c:277 smc_release+0x2dc/0x540 net/smc/af_smc.c:344 __sock_release net/socket.c:647 [inline] sock_close+0xbc/0x240 net/socket.c:1391 __fput+0x3e9/0x9f0 fs/file_table.c:465 task_work_run+0x251/0x310 kernel/task_work.c:227 get_signal+0x15db/0x1730 kernel/signal.c:2809 arch_do_signal_or_restart+0x98/0x840 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f12dad8d169 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:00007f12dbc59038 EFLAGS: 00000246 ORIG_RAX: 0000000000000120 RAX: fffffffffffffe00 RBX: 00007f12dafa6160 RCX: 00007f12dad8d169 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000009 RBP: 00007f12dae0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000800 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f12dafa6160 R15: 00007ffef7b47908