INFO: task kcompactd0:1660 blocked for more than 143 seconds. Not tainted 5.14.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kcompactd0 state:D stack:27952 pid: 1660 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4683 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5940 schedule+0xd3/0x270 kernel/sched/core.c:6019 io_schedule+0xba/0x130 kernel/sched/core.c:8008 wait_on_page_bit_common+0x537/0xe60 mm/filemap.c:1301 lock_page include/linux/pagemap.h:626 [inline] __unmap_and_move mm/migrate.c:986 [inline] unmap_and_move mm/migrate.c:1136 [inline] migrate_pages+0xa5d/0x3970 mm/migrate.c:1411 compact_zone+0x1ab9/0x3860 mm/compaction.c:2399 kcompactd_do_work+0x2c9/0x730 mm/compaction.c:2814 kcompactd+0x262/0xd10 mm/compaction.c:2909 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Showing all locks held in the system: 1 lock held by systemd/1: 1 lock held by khungtaskd/1656: #0: ffffffff8b97b9c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by kswapd1/2156: 3 locks held by kworker/1:2/2958: 2 locks held by systemd-journal/4869: 1 lock held by systemd-udevd/4874: 2 locks held by systemd-timesyn/4957: 2 locks held by in:imklog/8143: 2 locks held by cron/8141: 2 locks held by agetty/8312: #0: ffff888027f2f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc90000f382e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 2 locks held by agetty/8344: #0: ffff888027d6c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc90000f482e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 2 locks held by syz-fuzzer/8444: 2 locks held by syz-fuzzer/8445: 3 locks held by kworker/0:0/28826: 3 locks held by kworker/u4:9/1529: 3 locks held by kworker/u4:1/25515: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1656 Comm: khungtaskd Not tainted 5.14.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xd0a/0xfc0 kernel/hung_task.c:295 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2156 Comm: kswapd1 Not tainted 5.14.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x60 kernel/kcov.c:197 Code: ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 00 65 8b 05 c9 64 8c 7e 89 c1 48 8b 34 24 <81> e1 00 01 00 00 65 48 8b 14 25 00 f0 01 00 a9 00 01 ff 00 74 0e RSP: 0018:ffffc9000877f678 EFLAGS: 00000086 RAX: 0000000080000001 RBX: ffff88813fe44000 RCX: 0000000080000001 RDX: ffff88801b349c40 RSI: ffffffff819fd94f RDI: 0000000000000003 RBP: ffffea0005d0a9c0 R08: 0000000000000000 R09: ffffea0005d0a9c7 R10: ffffffff819fd938 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffea0005d0a9d0 R15: ffffea0005d0a9c0 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f50c62492e3 CR3: 0000000033cf2000 CR4: 0000000000350ee0 Call Trace: __page_memcg include/linux/memcontrol.h:406 [inline] page_memcg+0x2af/0x430 include/linux/memcontrol.h:455 page_matches_lruvec include/linux/memcontrol.h:1504 [inline] move_pages_to_lru+0x533/0x2160 mm/vmscan.c:2077 shrink_inactive_list mm/vmscan.c:2159 [inline] shrink_list mm/vmscan.c:2383 [inline] shrink_lruvec+0xbbf/0x2230 mm/vmscan.c:2678 shrink_node_memcgs mm/vmscan.c:2866 [inline] shrink_node+0x868/0x1df0 mm/vmscan.c:2983 kswapd_shrink_node mm/vmscan.c:3726 [inline] balance_pgdat+0x7ce/0x13b0 mm/vmscan.c:3917 kswapd+0x5b6/0xdb0 mm/vmscan.c:4176 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295