INFO: task syz.0.2256:14418 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2256 state:D stack:24584 pid:14418 tgid:14418 ppid:5839 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 pipe_release+0x48/0x330 fs/pipe.c:729 __fput+0x449/0xa70 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6adcb8eec9 RSP: 002b:00007fffe48d84e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f6adcde7da0 RCX: 00007f6adcb8eec9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f6adcde7da0 R08: 0000000000000eb0 R09: 00000011e48d87df R10: 00007f6adcde7cb0 R11: 0000000000000246 R12: 0000000000059eb5 R13: 00007f6adcde6270 R14: ffffffffffffffff R15: 00007fffe48d8600 INFO: task syz.0.2256:14429 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2256 state:D stack:28904 pid:14429 tgid:14418 ppid:5839 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 pipe_ioctl+0xc4/0x490 fs/pipe.c:626 vfs_ioctl fs/ioctl.c:51 [inline] do_vfs_ioctl+0xe67/0x1430 fs/ioctl.c:551 __do_sys_ioctl fs/ioctl.c:595 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6adcb8eec9 RSP: 002b:00007f6addaba038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f6adcde6090 RCX: 00007f6adcb8eec9 RDX: 0000000000000000 RSI: 000000000000541b RDI: 0000000000000007 RBP: 00007f6adcc11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6adcde6128 R14: 00007f6adcde6090 R15: 00007fffe48d8388 INFO: task syz.0.2256:14433 blocked for more than 146 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2256 state:D stack:28616 pid:14433 tgid:14418 ppid:5839 task_flags:0x400040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 anon_pipe_write+0x15d/0x1460 fs/pipe.c:458 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5c9/0xb30 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6adcb8eec9 RSP: 002b:00007f6adda99038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f6adcde6180 RCX: 00007f6adcb8eec9 RDX: 0000000000000001 RSI: 0000200000000000 RDI: 0000000000000007 RBP: 00007f6adcc11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6adcde6218 R14: 00007f6adcde6180 R15: 00007fffe48d8388 Showing all locks held in the system: 2 locks held by kworker/0:0/9: 1 lock held by khungtaskd/31: #0: ffffffff8e13d320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13d320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e13d320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5587: #0: ffff88814d98d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036be2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz.0.2256/14418: #0: ffff88804784b068 (&pipe->mutex){+.+.}-{4:4}, at: pipe_release+0x48/0x330 fs/pipe.c:729 1 lock held by syz.0.2256/14419: #0: ffff88804784b068 (&pipe->mutex){+.+.}-{4:4}, at: splice_file_to_pipe+0x2e/0x440 fs/splice.c:1289 1 lock held by syz.0.2256/14429: #0: ffff88804784b068 (&pipe->mutex){+.+.}-{4:4}, at: pipe_ioctl+0xc4/0x490 fs/pipe.c:626 1 lock held by syz.0.2256/14433: #0: ffff88804784b068 (&pipe->mutex){+.+.}-{4:4}, at: anon_pipe_write+0x15d/0x1460 fs/pipe.c:458 1 lock held by syz.5.2265/14451: 1 lock held by syz.5.2265/14468: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5827 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:__might_fault+0x5/0x130 mm/memory.c:7076 Code: e8 60 bd b2 ff 48 89 df 31 f6 e8 e6 09 fd ff e9 e8 fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 89 f5 49 89 fe 49 bc 00 00 00 00 00 fc RSP: 0018:ffffc9000410f910 EFLAGS: 00000293 RAX: ffffffff8168d83d RBX: 00007fffd0138340 RCX: ffff88803045dac0 RDX: 0000000000000000 RSI: 00000000000000b5 RDI: ffffffff8d80f827 RBP: ffffc9000410faf0 R08: ffffffff8f9e0f77 R09: 1ffffffff1f3c1ee R10: dffffc0000000000 R11: fffffbfff1f3c1ef R12: 00007fffd0138140 R13: dffffc0000000000 R14: 00007fffd0138140 R15: ffff88803045dac0 FS: 000055558bcaa500(0000) GS:ffff888125e0f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffb2cc2000 CR3: 0000000077ef4000 CR4: 00000000003526f0 Call Trace: __clear_user arch/x86/include/asm/uaccess_64.h:181 [inline] copy_fpstate_to_sigframe+0x13a/0xce0 arch/x86/kernel/fpu/signal.c:203 get_sigframe+0x58d/0x7d0 arch/x86/kernel/signal.c:163 x64_setup_rt_frame+0x15b/0xd40 arch/x86/kernel/signal_64.c:175 setup_rt_frame arch/x86/kernel/signal.c:250 [inline] handle_signal arch/x86/kernel/signal.c:294 [inline] arch_do_signal_or_restart+0x3f1/0x790 arch/x86/kernel/signal.c:339 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbb5a585017 Code: 89 7c 24 10 48 89 4c 24 18 e8 65 1c 03 00 4c 8b 54 24 18 8b 54 24 14 41 89 c0 48 8b 74 24 08 8b 7c 24 10 b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 89 44 24 10 e8 b5 1c 03 00 8b 44 RSP: 002b:00007fffd0138510 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000588 RCX: 00007fbb5a585017 RDX: 0000000040000001 RSI: 00007fffd013857c RDI: 00000000ffffffff RBP: 00007fffd013857c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000001388 R13: 00000000000927c0 R14: 000000000005a25c R15: 00007fffd01385d0