INFO: task syz.0.1776:14902 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1776 state:D stack:25384 pid:14902 tgid:14892 ppid:5813 task_flags:0x400140 flags:0x00080003 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7026 io_schedule+0xbf/0x130 kernel/sched/core.c:7871 folio_wait_bit_common+0x3d5/0x9e0 mm/filemap.c:1330 folio_lock include/linux/pagemap.h:1141 [inline] migrate_folio_unmap mm/migrate.c:1241 [inline] migrate_pages_batch+0x1487/0x3bb0 mm/migrate.c:1882 migrate_pages_sync+0x4c5/0x8a0 mm/migrate.c:2026 migrate_pages+0x1b5f/0x23a0 mm/migrate.c:2108 compact_zone+0x2018/0x4750 mm/compaction.c:2647 compact_node+0x1a3/0x2c0 mm/compaction.c:2916 compact_nodes mm/compaction.c:2938 [inline] sysctl_compaction_handler mm/compaction.c:2989 [inline] sysctl_compaction_handler+0x141/0x210 mm/compaction.c:2976 proc_sys_call_handler+0x445/0x570 fs/proc/proc_sysctl.c:600 iter_file_splice_write+0xa24/0x12e0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x192/0x6c0 fs/splice.c:1161 splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x174/0x240 fs/splice.c:1230 do_sendfile+0xb06/0xe50 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1425 [inline] __se_sys_sendfile64 fs/read_write.c:1417 [inline] __x64_sys_sendfile64+0x154/0x220 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdc4bf8f6c9 RSP: 002b:00007fdc4cd73038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fdc4c1e6270 RCX: 00007fdc4bf8f6c9 RDX: 00002000000000c0 RSI: 000000000000000b RDI: 000000000000000c RBP: 00007fdc4c011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000000a R11: 0000000000000246 R12: 0000000000000000 R13: 00007fdc4c1e6308 R14: 00007fdc4c1e6270 R15: 00007ffdbf6bc088 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e3c4720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3c4720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e3c4720 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775 2 locks held by getty/5578: #0: ffff888035bb90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 1 lock held by udevd/5811: #0: ffff888143311358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945 3 locks held by kworker/1:4/5888: #0: ffff88813ff11948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238 #1: ffffc90005297d00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239 #2: ffffffff8e3cfcb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:311 1 lock held by udevd/9328: #0: ffff888025cdc358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945 1 lock held by syz.0.1776/14902: #0: ffff88807bc10420 (sb_writers#3){.+.+}-{0:0}, at: splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105 1 lock held by syz.2.2086/16503: #0: ffffffff8e3cfcb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:343 1 lock held by syz.4.2088/16508: ============================================= NMI backtrace for cpu 1 CPU: 1 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 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:332 [inline] watchdog+0xf3f/0x1170 kernel/hung_task.c:495 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 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: 16508 Comm: syz.4.2088 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:pvclock_read_begin arch/x86/include/asm/pvclock.h:25 [inline] RIP: 0010:__pvclock_clocksource_read arch/x86/kernel/pvclock.c:76 [inline] RIP: 0010:pvclock_clocksource_read_nowd+0x11/0x100 arch/x86/kernel/pvclock.c:120 Code: 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 41 54 55 53 48 89 fb 48 83 ec 10 8b 17 <83> e2 fe 41 89 d4 0f 01 f9 66 90 48 c1 e2 20 8b 6b 18 48 09 c2 48 RSP: 0018:ffffc900042ef050 EFLAGS: 00000286 RAX: 0000000000000000 RBX: ffffffff93a7b000 RCX: ffffffff8217a442 RDX: 000000000000000a RSI: ffffffff822fa57b RDI: ffffffff93a7b000 RBP: 0000000000000000 R08: 0000000000000000 R09: fffff94000247c06 R10: ffffea000123e037 R11: 0000000000000001 R12: ffffea000123e000 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124a08000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9d9dbd3f98 CR3: 00000000332fd000 CR4: 00000000003526f0 Call Trace: kvm_sched_clock_read+0x11/0x20 arch/x86/kernel/kvmclock.c:91 local_clock_noinstr+0xd/0xe0 kernel/sched/clock.c:304 local_clock+0x10/0x30 kernel/sched/clock.c:318 __reset_page_owner+0x20/0x1a0 mm/page_owner.c:295 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] free_unref_folios+0xa31/0x1610 mm/page_alloc.c:2963 folios_put_refs+0x4be/0x750 mm/swap.c:1002 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x58f/0x1150 mm/shmem.c:1120 shmem_truncate_range mm/shmem.c:1232 [inline] shmem_evict_inode+0x3a1/0xbe0 mm/shmem.c:1360 evict+0x3e6/0x920 fs/inode.c:810 iput_final fs/inode.c:1914 [inline] iput.part.0+0x6a9/0xb00 fs/inode.c:1966 iput+0x35/0x40 fs/inode.c:1929 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:466 __dentry_kill+0x1d0/0x600 fs/dcache.c:669 shrink_kill fs/dcache.c:1114 [inline] shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1141 shrink_dcache_parent+0xe1/0x530 fs/dcache.c:1575 do_one_tree fs/dcache.c:1604 [inline] shrink_dcache_for_umount+0xa5/0x3e0 fs/dcache.c:1621 generic_shutdown_super+0x6c/0x390 fs/super.c:620 kill_anon_super fs/super.c:1281 [inline] kill_litter_super+0x70/0xa0 fs/super.c:1291 deactivate_locked_super+0xc1/0x1a0 fs/super.c:473 deactivate_super fs/super.c:506 [inline] deactivate_super+0xde/0x100 fs/super.c:502 cleanup_mnt+0x225/0x450 fs/namespace.c:1327 task_work_run+0x150/0x240 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x86f/0x2bf0 kernel/exit.c:966 do_group_exit+0xd3/0x2a0 kernel/exit.c:1107 get_signal+0x2671/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x85/0x130 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+0x426/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9d9cd8f6c9 Code: Unable to access opcode bytes at 0x7f9d9cd8f69f. RSP: 002b:00007f9d9dbd4038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: 000000000000006c RBX: 00007f9d9cfe6090 RCX: 00007f9d9cd8f6c9 RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000000003 RBP: 00007f9d9ce11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9d9cfe6128 R14: 00007f9d9cfe6090 R15: 00007ffc33a0a0e8