INFO: task syz-executor:5853 blocked for more than 143 seconds. Tainted: G U syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22936 pid:5853 tgid:5853 ppid:5852 task_flags:0x400100 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760 pipe_release+0x44/0x320 fs/pipe.c:727 __fput+0x3ff/0xb70 fs/file_table.c:468 fput_close_sync+0x118/0x210 fs/file_table.c:573 __do_sys_close fs/open.c:1587 [inline] __se_sys_close fs/open.c:1572 [inline] __x64_sys_close+0x8b/0x120 fs/open.c:1572 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc7ab18db00 RSP: 002b:00007fff0a7b1508 EFLAGS: 00000202 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 0000555580599d50 RCX: 00007fc7ab18db00 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 000000000000001f RBP: 0000555580596720 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000202 R12: 00007fff0a7b1530 R13: 000000000000001d R14: 0000555580599d9c R15: 00005555805ab628 INFO: task syz.2.4920:27771 blocked for more than 143 seconds. Tainted: G U syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.4920 state:D stack:28856 pid:27771 tgid:27760 ppid:19405 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x81b/0x1060 kernel/locking/mutex.c:760 tracing_splice_read_pipe+0x180/0xdc0 kernel/trace/trace.c:6857 do_splice_read fs/splice.c:982 [inline] do_splice_read+0x282/0x370 fs/splice.c:956 splice_file_to_pipe+0x109/0x120 fs/splice.c:1292 do_sendfile+0x400/0xe50 fs/read_write.c:1376 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64 fs/read_write.c:1417 [inline] __x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcb57d8eec9 RSP: 002b:00007fcb58b94038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fcb57fe6090 RCX: 00007fcb57d8eec9 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000001 RBP: 00007fcb57e11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000007ffff000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcb57fe6128 R14: 00007fcb57fe6090 R15: 00007fff7b37e0b8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c1420 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c1420 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c1420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 1 lock held by syz-executor/5853: #0: ffff88807e42e868 (&pipe->mutex){+.+.}-{4:4}, at: pipe_release+0x44/0x320 fs/pipe.c:727 2 locks held by kworker/u9:6/5878: #0: ffff888026810148 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc9000423fd10 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 2 locks held by kworker/u9:0/15278: #0: ffff88802637b148 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90012d77d10 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 2 locks held by kworker/u9:1/15282: #0: ffff888026391948 ((wq_completion)nbd2-recv){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3211 #1: ffffc90012d57d10 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3212 2 locks held by getty/23178: #0: ffff88814d0310a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900040eb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 2 locks held by syz.2.4920/27763: 2 locks held by syz.2.4920/27771: #0: ffff88807e42e868 (&pipe->mutex){+.+.}-{4:4}, at: pipe_lock fs/pipe.c:91 [inline] #0: ffff88807e42e868 (&pipe->mutex){+.+.}-{4:4}, at: pipe_lock+0x64/0x80 fs/pipe.c:88 #1: ffff88806b3d0090 (&iter->mutex){+.+.}-{4:4}, at: tracing_splice_read_pipe+0x180/0xdc0 kernel/trace/trace.c:6857 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G U syzkaller #0 PREEMPT(full) Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf0e/0x1260 kernel/hung_task.c:491 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x56d/0x730 arch/x86/kernel/process.c:148 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: 27763 Comm: syz.2.4920 Tainted: G U syzkaller #0 PREEMPT(full) Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:check_region_inline mm/kasan/generic.c:174 [inline] RIP: 0010:kasan_check_range+0x16/0x1b0 mm/kasan/generic.c:189 Code: 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 85 f6 0f 84 64 01 00 00 48 89 f8 41 54 44 0f b6 c2 <48> 01 f0 55 53 0f 82 d7 00 00 00 eb 0f cc cc cc 48 b8 00 00 00 00 RSP: 0018:ffffc9000b727b10 EFLAGS: 00000002 RAX: ffff88801b888818 RBX: ffff88801b888818 RCX: ffffffff8197b033 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88801b888818 RBP: 0000000000000200 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88801b888818 R14: 0000000000000000 R15: ffff88801b8888e0 FS: 00007fcb58bb56c0(0000) GS:ffff8881246ba000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556d23518168 CR3: 00000000636c0000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] queued_spin_is_locked include/asm-generic/qspinlock.h:57 [inline] debug_spin_unlock kernel/locking/spinlock_debug.c:101 [inline] do_raw_spin_unlock+0x53/0x230 kernel/locking/spinlock_debug.c:141 __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_unlock+0x1e/0x50 kernel/locking/spinlock.c:186 rb_reader_unlock kernel/trace/ring_buffer.c:5811 [inline] ring_buffer_empty_cpu+0x1cc/0x3b0 kernel/trace/ring_buffer.c:6349 trace_empty+0x2d7/0x360 kernel/trace/trace.c:4368 tracing_read_pipe+0x38b/0xd30 kernel/trace/trace.c:6712 do_loop_readv_writev fs/read_write.c:847 [inline] do_loop_readv_writev fs/read_write.c:835 [inline] vfs_readv+0x5be/0x8b0 fs/read_write.c:1020 do_readv+0x132/0x340 fs/read_write.c:1080 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcb57d8eec9 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:00007fcb58bb5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000013 RAX: ffffffffffffffda RBX: 00007fcb57fe5fa0 RCX: 00007fcb57d8eec9 RDX: 0000000000000001 RSI: 0000200000000a80 RDI: 0000000000000003 RBP: 00007fcb57e11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcb57fe6038 R14: 00007fcb57fe5fa0 R15: 00007fff7b37e0b8