INFO: task syz.9.489:9836 blocked for more than 143 seconds. Not tainted 6.15.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.9.489 state:D stack:25272 pid:9836 tgid:9835 ppid:8664 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 __super_lock fs/super.c:58 [inline] super_lock+0x2a9/0x3b0 fs/super.c:120 super_lock_shared fs/super.c:139 [inline] iterate_supers+0x80/0x180 fs/super.c:931 ksys_sync+0x94/0x150 fs/sync.c:102 __ia32_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe92238e969 RSP: 002b:00007fe92311d038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fe9225b5fa0 RCX: 00007fe92238e969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fe9225b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe9225b5fa0 R15: 00007ffde63e8348 INFO: task syz.7.491:9850 blocked for more than 144 seconds. Not tainted 6.15.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.7.491 state:D stack:28952 pid:9850 tgid:9849 ppid:7321 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526 __super_lock fs/super.c:58 [inline] super_lock+0x2a9/0x3b0 fs/super.c:120 super_lock_shared fs/super.c:139 [inline] iterate_supers+0x80/0x180 fs/super.c:931 ksys_sync+0x94/0x150 fs/sync.c:102 __ia32_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f241df8e969 RSP: 002b:00007f241ed35038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f241e1b5fa0 RCX: 00007f241df8e969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f241e1b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f241e1b5fa0 R15: 00007ffd1aebf5c8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5578: #0: ffff8880309290a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by syz-executor/5820: 2 locks held by kworker/u8:9/6059: 1 lock held by syz.9.489/9836: #0: ffff888027f1c0e0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888027f1c0e0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.7.491/9850: #0: ffff888027f1c0e0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff888027f1c0e0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz-executor/10050: #0: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 1 lock held by syz.0.585/10752: #0: ffff888027f1c0e0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888027f1c0e0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x25c/0x3b0 fs/super.c:120 1 lock held by syz.0.585/10783: #0: ffff888027f1c0e0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888027f1c0e0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x25c/0x3b0 fs/super.c:120 2 locks held by syz-executor/10916: 3 locks held by syz.2.715/11949: 2 locks held by dhcpcd/11995: #0: ffff88805a30ee08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff88805a30ee08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff88805a30ee08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1391 #1: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #1: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 1 lock held by udevadm/12000: 1 lock held by sed/12002: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc7-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x711/0x8a0 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 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5806 Comm: syz-executor Not tainted 6.15.0-rc7-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3802 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3822 [inline] RIP: 0010:validate_chain+0xa4/0x2140 kernel/locking/lockdep.c:3877 Code: c6 30 c3 81 8d e8 ec c7 e5 ff 90 0f 0b 90 90 90 48 bb eb 83 b5 80 46 86 c8 61 49 0f af df 48 c1 eb 2d 48 8b 04 dd 10 37 36 93 <48> 85 c0 0f 94 c1 48 83 c0 f8 0f 94 c2 08 ca 0f 84 24 01 00 00 e8 RSP: 0018:ffffc900044df9c8 EFLAGS: 00000003 RAX: ffffffff937a3b88 RBX: 0000000000005713 RCX: 0000000000040000 RDX: 0000000000000001 RSI: ffff888079eba8f0 RDI: ffff888079eb9e00 RBP: ffff888079eba8f0 R08: 0000000000000000 R09: 0000000000080000 R10: 0000000000000000 R11: ffffffff84b7d76a R12: 0000000000000001 R13: 3df1592f76153240 R14: ffff888079eba8f0 R15: 3df1592f76153240 FS: 0000555586f98500(0000) GS:ffff8881260f6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa91124b1d4 CR3: 0000000079c3c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162 debug_object_free+0x9a/0x340 lib/debugobjects.c:962 destroy_hrtimer_on_stack kernel/time/hrtimer.c:455 [inline] hrtimer_nanosleep+0x2a6/0x360 kernel/time/hrtimer.c:2162 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1407 [inline] __se_sys_clock_nanosleep+0x2f1/0x380 kernel/time/posix-timers.c:1384 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f39b15c11e3 Code: 1f 84 00 00 00 00 00 83 ff 03 74 7b 83 ff 02 b8 fa ff ff ff 49 89 ca 0f 44 f8 80 3d 5e 33 1c 00 00 74 14 b8 e6 00 00 00 0f 05 d8 c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec 28 48 89 54 24 10 RSP: 002b:00007fffb21580d8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f39b15c11e3 RDX: 00007fffb21580f0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00000000047a7de6 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000202 R12: 00007fffb2158540 R13: 0000000000000004 R14: 00007fffb215812c R15: 00007fffb21581c0