INFO: task syz.6.395:7955 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.395 state:D stack:24352 pid:7955 tgid:7952 ppid:7120 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5256 [inline] __schedule+0x145f/0x5070 kernel/sched/core.c:6863 __schedule_loop kernel/sched/core.c:6945 [inline] schedule+0x165/0x360 kernel/sched/core.c:6960 io_schedule+0x81/0xe0 kernel/sched/core.c:7789 folio_wait_bit_common+0x6b5/0xb90 mm/filemap.c:1323 folio_lock include/linux/pagemap.h:1159 [inline] migrate_folio_unmap mm/migrate.c:1249 [inline] migrate_pages_batch+0x10ab/0x2ec0 mm/migrate.c:1890 migrate_pages_sync mm/migrate.c:2034 [inline] migrate_pages+0x1feb/0x28c0 mm/migrate.c:2116 compact_zone+0x25cf/0x4770 mm/compaction.c:2647 compact_node mm/compaction.c:2916 [inline] compact_nodes mm/compaction.c:2938 [inline] sysctl_compaction_handler+0x3a1/0x7b0 mm/compaction.c:2989 proc_sys_call_handler+0x4cc/0x700 fs/proc/proc_sysctl.c:600 iter_file_splice_write+0x977/0x10b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x104/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5b3/0xcd0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x187/0x270 fs/splice.c:1230 do_sendfile+0x4ec/0x7f0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1425 [inline] __se_sys_sendfile64+0xd9/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd05ac5f749 RSP: 002b:00007fd058e7c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007fd05aeb6180 RCX: 00007fd05ac5f749 RDX: 00002000000000c0 RSI: 0000000000000008 RDI: 0000000000000009 RBP: 00007fd05ace3f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd05aeb6218 R14: 00007fd05aeb6180 R15: 00007ffdfdb9c748 Showing all locks held in the system: 4 locks held by ktimers/0/16: 1 lock held by khungtaskd/38: #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5564: #0: ffff88803013e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x44f/0x1460 drivers/tty/n_tty.c:2211 4 locks held by kworker/0:4/5845: 3 locks held by kworker/1:8/5955: 1 lock held by udevd/6777: #0: ffff8880248314c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xcc0 block/bdev.c:962 1 lock held by syz-executor/7024: 1 lock held by syz.6.395/7955: #0: ffff888070298480 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1160 1 lock held by syz.2.895/9875: 2 locks held by syz-executor/9975: #0: ffffffff8e021f08 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e021f08 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e021f08 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071 6 locks held by syz.9.958/10035: 5 locks held by syz.3.960/10038: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 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] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf95/0xfe0 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 10038 Comm: syz.3.960 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:lock_is_held_type+0x0/0x150 kernel/locking/lockdep.c:5925 Code: 8d 3d 34 a6 0c 04 48 c7 c6 ae d2 f7 8c 67 48 0f b9 3a 90 eb ce 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 41 57 41 56 41 55 41 54 53 bb ff ff ff ff 83 3d f6 RSP: 0018:ffffc9000629f630 EFLAGS: 00000202 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffff88802d371e40 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8d5aea00 RBP: ffffffff897b75a1 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc9000629f780 R11: fffff52000c53ef4 R12: ffff888039485800 R13: dffffc0000000000 R14: ffff888039485f98 R15: ffffc9000629f7c0 FS: 00007f60d3ed56c0(0000) GS:ffff888126cef000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055558d0bc5c8 CR3: 00000000293ea000 CR4: 00000000003526f0 Call Trace: lock_is_held include/linux/lockdep.h:249 [inline] __might_resched+0x37/0x480 kernel/sched/core.c:8789 __mutex_lock_common kernel/locking/rtmutex_api.c:532 [inline] mutex_lock_nested+0x37/0x1d0 kernel/locking/rtmutex_api.c:552 __unix_dgram_recvmsg+0x1e1/0xd60 net/unix/af_unix.c:2573 sock_recvmsg_nosec+0x186/0x1c0 net/socket.c:1078 ____sys_recvmsg+0x3ab/0x470 net/socket.c:2810 ___sys_recvmsg+0x1b5/0x510 net/socket.c:2854 do_recvmmsg+0x30d/0x770 net/socket.c:2949 __sys_recvmmsg net/socket.c:3023 [inline] __do_sys_recvmmsg net/socket.c:3046 [inline] __se_sys_recvmmsg net/socket.c:3039 [inline] __x64_sys_recvmmsg+0x190/0x240 net/socket.c:3039 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f60d5c8f749 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:00007f60d3ed5038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f60d5ee6090 RCX: 00007f60d5c8f749 RDX: 00000000080002c1 RSI: 0000200000000040 RDI: 0000000000000003 RBP: 00007f60d5d13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f60d5ee6128 R14: 00007f60d5ee6090 R15: 00007ffd1ec34068