INFO: task kcompactd0:1651 blocked for more than 143 seconds. Not tainted 5.10.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kcompactd0 state:D stack:27584 pid: 1651 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:3774 [inline] __schedule+0x92c/0xcb0 kernel/sched/core.c:4523 schedule+0x14b/0x200 kernel/sched/core.c:4601 io_schedule+0x86/0xf0 kernel/sched/core.c:6295 wait_on_page_bit_common+0xa84/0xfc0 mm/filemap.c:1273 lock_page include/linux/pagemap.h:611 [inline] __unmap_and_move+0x859/0xbf0 mm/migrate.c:1047 unmap_and_move+0x2cd/0x10d0 mm/migrate.c:1197 migrate_pages+0x41e/0xf70 mm/migrate.c:1453 compact_zone+0x2c49/0x3ac0 mm/compaction.c:2314 kcompactd_do_work mm/compaction.c:2724 [inline] kcompactd+0x70f/0x2530 mm/compaction.c:2819 kthread+0x36b/0x390 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Showing all locks held in the system: 1 lock held by systemd/1: 1 lock held by khungtaskd/1647: #0: ffffffff8bae6840 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 arch/x86/pci/mmconfig_64.c:151 3 locks held by kswapd0/2182: 1 lock held by kswapd1/2183: 2 locks held by systemd-journal/4869: 2 locks held by systemd-udevd/4894: 1 lock held by systemd-timesyn/4977: 2 locks held by in:imklog/8147: 2 locks held by cron/8130: 2 locks held by agetty/8166: #0: ffff88801bc8b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:266 #1: ffffc90000f5c2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x260/0x1b40 drivers/tty/n_tty.c:2156 2 locks held by agetty/8168: #0: ffff888021fd8098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:266 #1: ffffc90000fa82e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x260/0x1b40 drivers/tty/n_tty.c:2156 2 locks held by syz-fuzzer/8461: 3 locks held by syz-fuzzer/8464: 2 locks held by syz-fuzzer/8473: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1647 Comm: khungtaskd Not tainted 5.10.0-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:77 [inline] dump_stack+0x137/0x1be lib/dump_stack.c:118 nmi_cpu_backtrace+0x16c/0x190 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x191/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xcb0/0xcf0 kernel/hung_task.c:294 kthread+0x36b/0x390 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8464 Comm: syz-fuzzer Not tainted 5.10.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:match_held_lock+0x13/0x190 kernel/locking/lockdep.c:4889 Code: 05 6e 33 c5 76 00 00 00 00 eb b5 e8 87 fc ff ff 0f 1f 80 00 00 00 00 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 01 00 00 00 48 39 77 10 74 52 81 7f 20 00 00 10 00 72 47 48 8b RSP: 0000:ffffc900012aee98 EFLAGS: 00000082 RAX: aec0e4274bec3b00 RBX: 0000000000000002 RCX: 0000000080000002 RDX: 0000000000000000 RSI: ffffffff8bae67a0 RDI: ffff8880181c5820 RBP: ffff8880181c5820 R08: dffffc0000000000 R09: fffffbfff19dc17e R10: fffffbfff19dc17e R11: 0000000000000000 R12: 0000000000000002 R13: ffff8880181c4ec0 R14: 00000000ffffffff R15: ffffffff8bae67a0 FS: 000000c00003ee90(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee25926303 CR3: 0000000013814000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_is_held kernel/locking/lockdep.c:5184 [inline] lock_is_held_type+0x81/0x140 kernel/locking/lockdep.c:5475 lock_is_held include/linux/lockdep.h:271 [inline] rcu_read_lock_sched_held+0x41/0xb0 kernel/rcu/update.c:123 trace_lock_acquire+0x6b/0x180 include/trace/events/lock.h:13 lock_acquire+0x39/0x5e0 kernel/locking/lockdep.c:5407 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:248 rcu_read_lock include/linux/rcupdate.h:641 [inline] page_evictable+0x23/0x290 mm/internal.h:83 move_pages_to_lru+0x22f/0x14c0 mm/vmscan.c:1855 shrink_inactive_list+0x38a/0x910 mm/vmscan.c:1965 shrink_list mm/vmscan.c:2170 [inline] shrink_lruvec+0x409/0x950 mm/vmscan.c:2465 shrink_node_memcgs+0x323/0x6d0 mm/vmscan.c:2653 shrink_node+0xc48/0x1ad0 mm/vmscan.c:2770 shrink_zones+0x414/0x8d0 mm/vmscan.c:2973 do_try_to_free_pages+0x205/0xa20 mm/vmscan.c:3028 try_to_free_pages+0x324/0xb00 mm/vmscan.c:3267 __perform_reclaim mm/page_alloc.c:4330 [inline] __alloc_pages_direct_reclaim mm/page_alloc.c:4351 [inline] __alloc_pages_slowpath+0xf1d/0x23c0 mm/page_alloc.c:4755 __alloc_pages_nodemask+0x31f/0x4f0 mm/page_alloc.c:4965 alloc_pages include/linux/gfp.h:547 [inline] __page_cache_alloc+0x79/0x1d0 mm/filemap.c:977 pagecache_get_page+0x85f/0xf80 mm/filemap.c:1828 filemap_fault+0x1840/0x2560 mm/filemap.c:2725 ext4_filemap_fault+0x82/0xa0 fs/ext4/inode.c:6192 __do_fault+0x139/0x3b0 mm/memory.c:3612 do_read_fault+0x5db/0xaa0 mm/memory.c:4006 do_fault mm/memory.c:4134 [inline] handle_pte_fault mm/memory.c:4374 [inline] __handle_mm_fault mm/memory.c:4509 [inline] handle_mm_fault+0x183c/0x2590 mm/memory.c:4607 do_user_addr_fault+0x4ca/0xa40 arch/x86/mm/fault.c:1372 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0xa1/0x1e0 arch/x86/mm/fault.c:1485 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:583 RIP: 0033:0x79e5e3 Code: Unable to access opcode bytes at RIP 0x79e5b9. RSP: 002b:000000c003c48ff8 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 0000000000ea53c0 RCX: 0000000000000002 RDX: 0000000000f30b00 RSI: 0000000000000000 RDI: 0000000000b4c9a0 RBP: 000000c003c49028 R08: 0000000000879d60 R09: 0000000000000001 R10: 000000c006a6b0e0 R11: ffffffffffffffff R12: 000000000000010f R13: 000000000000010e R14: 0000000000000200 R15: 0000000000000200