====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc1-syzkaller-00081-gbb066fe812d6 #0 Not tainted ------------------------------------------------------ syz.0.5691/17310 is trying to acquire lock: ffff88804eadb750 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] ffff88804eadb750 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] ffff88804eadb750 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: start_flush_work kernel/workqueue.c:4148 [inline] ffff88804eadb750 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: __flush_work+0xe9/0xc60 kernel/workqueue.c:4206 but task is already holding lock: ffff88804ead8dd8 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x234/0x540 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+0x1ed/0x550 kernel/locking/lockdep.c:5851 lock_sock_nested+0x48/0x100 net/core/sock.c:3645 smc_listen_out+0x11b/0x3e0 net/smc/af_smc.c:1908 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 touch_work_lockdep_map kernel/workqueue.c:3920 [inline] start_flush_work kernel/workqueue.c:4174 [inline] __flush_work+0x739/0xc60 kernel/workqueue.c:4206 __cancel_work_sync+0xbc/0x110 kernel/workqueue.c:4362 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:642 [inline] sock_close+0xbc/0x240 net/socket.c:1393 __fput+0x3e9/0x9f0 fs/file_table.c:448 task_work_run+0x24f/0x310 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 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.0.5691/17310: #0: ffff8880424ace08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:865 [inline] #0: ffff8880424ace08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:641 [inline] #0: ffff8880424ace08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1393 #1: ffff88804ead8dd8 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x234/0x540 #2: ffffffff8e9387e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #2: ffffffff8e9387e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8e9387e0 (rcu_read_lock){....}-{1:3}, at: start_flush_work kernel/workqueue.c:4148 [inline] #2: ffffffff8e9387e0 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xe9/0xc60 kernel/workqueue.c:4206 stack backtrace: CPU: 0 UID: 0 PID: 17310 Comm: syz.0.5691 Not tainted 6.14.0-rc1-syzkaller-00081-gbb066fe812d6 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2076 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208 check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 touch_work_lockdep_map kernel/workqueue.c:3920 [inline] start_flush_work kernel/workqueue.c:4174 [inline] __flush_work+0x739/0xc60 kernel/workqueue.c:4206 __cancel_work_sync+0xbc/0x110 kernel/workqueue.c:4362 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:642 [inline] sock_close+0xbc/0x240 net/socket.c:1393 __fput+0x3e9/0x9f0 fs/file_table.c:448 task_work_run+0x24f/0x310 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x13f/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fce8fb8cde9 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:00007ffccbe4b868 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00000000000830c9 RCX: 00007fce8fb8cde9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fce8fda7ba0 R08: 0000000000000001 R09: 00000007cbe4bb5f R10: 00007fce8fa00000 R11: 0000000000000246 R12: 00007fce8fda5fac R13: 00007fce8fda5fa0 R14: ffffffffffffffff R15: 00007ffccbe4b980