INFO: task syz.0.1924:12203 blocked for more than 143 seconds. Not tainted 6.13.0-rc2-syzkaller-00333-ga0e3919a2df2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1924 state:D stack:27744 pid:12203 tgid:12199 ppid:5830 flags:0x00400004 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905 __mutex_lock_common kernel/locking/mutex.c:665 [inline] __mutex_lock+0x62b/0xa60 kernel/locking/mutex.c:735 nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625 nfsd_umount+0x48/0xe0 fs/nfsd/nfsctl.c:1428 deactivate_locked_super+0xbe/0x1a0 fs/super.c:473 deactivate_super+0xde/0x100 fs/super.c:506 cleanup_mnt+0x222/0x450 fs/namespace.c:1373 task_work_run+0x14e/0x250 kernel/task_work.c:239 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+0x27b/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6654f85d19 RSP: 002b:00007f6655ddd038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffea RBX: 00007f6655176080 RCX: 00007f6654f85d19 RDX: 0000000020000280 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 00007f6655001a20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000006 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6655176080 R15: 00007fff5f4c9fa8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8ddba940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8ddba940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8ddba940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6744 3 locks held by kworker/1:1/51: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3204 #1: ffffc90000bb7d80 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205 #2: ffff88807ba8d240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1ce/0x3190 drivers/net/netdevsim/fib.c:1490 2 locks held by kworker/u9:0/53: #0: ffff888025918148 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3204 #1: ffffc90000be7d80 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205 4 locks held by kworker/u8:3/54: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3204 #1: ffffc90000bf7d80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205 #2: ffffffff8fabe008 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:281 #3: ffffffff8ddc6278 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297 2 locks held by kworker/u9:1/5146: #0: ffff888025969148 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3204 #1: ffffc9001020fd80 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205 2 locks held by kworker/u8:11/7369: 3 locks held by kworker/u8:18/7376: #0: ffff88814ce8d948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12cd/0x1b30 kernel/workqueue.c:3204 #1: ffffc90003dffd80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205 #2: ffffffff8fabe008 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0xcf/0x14d0 net/ipv6/addrconf.c:4215 2 locks held by syz.3.1912/12167: #0: ffffffff8fb5c850 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e1b9808 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xe3/0x1b40 fs/nfsd/nfsctl.c:1964 2 locks held by syz.0.1924/12203: #0: ffff88807d9980e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807d9980e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807d9980e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:505 #1: ffffffff8e1b9808 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625 2 locks held by syz-executor/12469: #0: ffff888074b7e0e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888074b7e0e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888074b7e0e0 (&type->s_umount_key#51){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:505 #1: ffffffff8e1b9808 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:625 1 lock held by syz-executor/12761: 1 lock held by syz-executor/12770: #0: ffffffff8ddc6278 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329 2 locks held by syz.5.2203/13218: #0: ffffffff8fb5c850 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e1b9808 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0xe3/0x1b40 fs/nfsd/nfsctl.c:1964 2 locks held by syz-executor/13496: 2 locks held by syz.6.2622/14760: #0: ffffffff8fb5c850 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e1b9808 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x694/0xbe0 fs/nfsd/nfsctl.c:1671 2 locks held by syz.7.2619/14761: 1 lock held by syz-executor/14777: #0: ffffffff8fabe008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline] #0: ffffffff8fabe008 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x316/0x1580 net/ipv4/devinet.c:987 3 locks held by syz.7.2631/14802: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc2-syzkaller-00333-ga0e3919a2df2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xf14/0x1240 kernel/hung_task.c:397 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 12761 Comm: syz-executor Not tainted 6.13.0-rc2-syzkaller-00333-ga0e3919a2df2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 RIP: 0010:hlock_class+0x56/0x130 kernel/locking/lockdep.c:228 Code: 20 66 81 e3 ff 1f 0f b7 db be 08 00 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 c0 4c 9b 96 e8 32 7e 86 00 48 0f a3 1d 2a fd 25 15 <73> 13 48 69 c3 c8 00 00 00 5b 48 05 e0 50 9b 96 c3 cc cc cc cc 48 RSP: 0018:ffffc90017c97650 EFLAGS: 00000047 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff81754f8e RDX: fffffbfff2d36999 RSI: 0000000000000008 RDI: ffffffff969b4cc0 RBP: 0000000000000002 R08: 0000000000000000 R09: fffffbfff2d36998 R10: ffffffff969b4cc7 R11: 0000000000000000 R12: 0000000000000000 R13: ffff888060a41e00 R14: 0000000000000000 R15: ffff888060a428e0 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000194d000 CR3: 000000007bf72000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: check_wait_context kernel/locking/lockdep.c:4851 [inline] __lock_acquire+0x44d/0x3c40 kernel/locking/lockdep.c:5176 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 __debug_check_no_obj_freed lib/debugobjects.c:1088 [inline] debug_check_no_obj_freed+0x1cf/0x600 lib/debugobjects.c:1129 remove_vm_area+0x1ae/0x3f0 mm/vmalloc.c:3241 vfree+0x90/0x890 mm/vmalloc.c:3364 kcov_put kernel/kcov.c:439 [inline] kcov_put+0x2a/0x40 kernel/kcov.c:435 kcov_close+0xd/0x20 kernel/kcov.c:535 __fput+0x3f8/0xb60 fs/file_table.c:450 task_work_run+0x14e/0x250 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xadd/0x2d70 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x2576/0x2610 kernel/signal.c:3017 arch_do_signal_or_restart+0x90/0x7e0 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+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f844b57bf53 Code: Unable to access opcode bytes at 0x7f844b57bf29. RSP: 002b:00007ffcd8d4a848 EFLAGS: 00000202 ORIG_RAX: 000000000000003d RAX: fffffffffffffe00 RBX: 00000000000031e2 RCX: 00007f844b57bf53 RDX: 0000000040000000 RSI: 00007ffcd8d4a85c RDI: 00000000ffffffff RBP: 00007ffcd8d4a85c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000