INFO: task kworker/u8:5:71 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:5 state:D stack:21760 pid:71 tgid:71 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-btrfs-13)
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14de/0x5210 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
wait_extent_bit fs/btrfs/extent-io-tree.c:811 [inline]
btrfs_lock_extent_bits+0x59c/0x700 fs/btrfs/extent-io-tree.c:1914
btrfs_lock_extent fs/btrfs/extent-io-tree.h:152 [inline]
btrfs_invalidate_folio+0x43d/0xc40 fs/btrfs/inode.c:7665
extent_writepage fs/btrfs/extent_io.c:1842 [inline]
extent_write_cache_pages fs/btrfs/extent_io.c:2570 [inline]
btrfs_writepages+0x12f3/0x23f0 fs/btrfs/extent_io.c:2703
do_writepages+0x32e/0x550 mm/page-writeback.c:2598
__writeback_single_inode+0x133/0x1060 fs/fs-writeback.c:1750
writeback_sb_inodes+0x92e/0x1910 fs/fs-writeback.c:2041
wb_writeback+0x445/0xad0 fs/fs-writeback.c:2227
wb_do_writeback fs/fs-writeback.c:2374 [inline]
wb_workfn+0x3fd/0xf00 fs/fs-writeback.c:2414
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3358
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task syz.2.81:6473 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.81 state:D stack:22808 pid:6473 tgid:6472 ppid:5794 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14de/0x5210 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
wait_current_trans+0x39f/0x590 fs/btrfs/transaction.c:535
start_transaction+0x6a7/0x15f0 fs/btrfs/transaction.c:705
clone_copy_inline_extent fs/btrfs/reflink.c:299 [inline]
btrfs_clone+0x128a/0x24d0 fs/btrfs/reflink.c:529
btrfs_clone_files+0x271/0x3f0 fs/btrfs/reflink.c:750
btrfs_remap_file_range+0x76b/0x1320 fs/btrfs/reflink.c:903
vfs_clone_file_range+0x435/0x7b0 fs/remap_range.c:403
ioctl_file_clone fs/ioctl.c:239 [inline]
ioctl_file_clone_range fs/ioctl.c:257 [inline]
do_vfs_ioctl+0xe15/0x1540 fs/ioctl.c:544
__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+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98d585bf79
RSP: 002b:00007f98d3ab6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f98d5ad5fa0 RCX: 00007f98d585bf79
RDX: 00002000000000c0 RSI: 000000004020940d RDI: 0000000000000006
RBP: 00007f98d58f27e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f98d5ad6038 R14: 00007f98d5ad5fa0 R15: 00007ffcbd8e3c38
INFO: task syz.2.81:6502 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.81 state:D stack:24696 pid:6502 tgid:6472 ppid:5794 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14de/0x5210 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
wb_wait_for_completion+0x372/0x690 fs/fs-writeback.c:226
__writeback_inodes_sb_nr+0x24c/0x2d0 fs/fs-writeback.c:2838
try_to_writeback_inodes_sb+0x9a/0xc0 fs/fs-writeback.c:2886
btrfs_start_delalloc_flush fs/btrfs/transaction.c:2159 [inline]
btrfs_commit_transaction+0x82e/0x31a0 fs/btrfs/transaction.c:2348
btrfs_ioctl+0xca7/0xd00 fs/btrfs/ioctl.c:5178
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xff/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98d585bf79
RSP: 002b:00007f98d3a95028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f98d5ad6090 RCX: 00007f98d585bf79
RDX: 0000000000000000 RSI: 0000000000009408 RDI: 0000000000000004
RBP: 00007f98d58f27e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f98d5ad6128 R14: 00007f98d5ad6090 R15: 00007ffcbd8e3c38
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:5/71:
#0: ffff88801aaec138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88801aaec138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3358
#1: ffffc9000156fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc9000156fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3358
2 locks held by getty/5548:
#0: ffff88802841c0a0 (&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+0x462/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by udevd/5912:
#0: ffff888019e87238 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0x9e/0x5e0 fs/kernfs/dir.c:1185
4 locks held by syz.2.81/6473:
#0: ffff888035c5a480 (sb_writers#15){.+.+}-{0:0}, at: ioctl_file_clone fs/ioctl.c:239 [inline]
#0: ffff888035c5a480 (sb_writers#15){.+.+}-{0:0}, at: ioctl_file_clone_range fs/ioctl.c:257 [inline]
#0: ffff888035c5a480 (sb_writers#15){.+.+}-{0:0}, at: do_vfs_ioctl+0xe15/0x1540 fs/ioctl.c:544
#1: ffff8880629f6dc0 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#1: ffff8880629f6dc0 (&sb->s_type->i_mutex_key#27){++++}-{4:4}, at: btrfs_inode_lock+0x51/0xe0 fs/btrfs/inode.c:370
#2: ffff8880629f6c18 (&ei->i_mmap_lock){+.+.}-{4:4}, at: btrfs_inode_lock+0xcb/0xe0 fs/btrfs/inode.c:373
#3: ffff888035c5a770 (sb_internal#3){.+.+}-{0:0}, at: clone_copy_inline_extent fs/btrfs/reflink.c:299 [inline]
#3: ffff888035c5a770 (sb_internal#3){.+.+}-{0:0}, at: btrfs_clone+0x128a/0x24d0 fs/btrfs/reflink.c:529
3 locks held by syz.2.81/6502:
#0: ffff888038c0b118 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x41b/0xc90 fs/btrfs/transaction.c:298
#1: ffff888038c0b140 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x41b/0xc90 fs/btrfs/transaction.c:298
#2: ffff888035c5a0d0 (&type->s_umount_key#62){++++}-{4:4}, at: try_to_writeback_inodes_sb+0x22/0xc0 fs/fs-writeback.c:2883
1 lock held by btrfs-transacti/6491:
#0: ffff888038c08d98 (&fs_info->transaction_kthread_mutex){+.+.}-{4:4}, at: transaction_kthread+0xe4/0x450 fs/btrfs/disk-io.c:1515
6 locks held by kworker/u8:50/6649:
#0: ffff88801b289138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88801b289138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3358
#1: ffffc900107f7c40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc900107f7c40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3358
#2: ffffffff8ef3f800 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670
#3: ffff8880601680d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#3: ffff8880601680d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
#3: ffff8880601680d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x117/0x3f0 net/devlink/core.c:506
#4: ffff888021300300 (&devlink->lock_key#8){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
#4: ffff888021300300 (&devlink->lock_key#8){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
#4: ffff888021300300 (&devlink->lock_key#8){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x3f0 net/devlink/core.c:506
#5: ffffffff8ef4e138 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#5: ffffffff8ef4e138 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_dev_lock+0x257/0x2f0 net/core/dev.c:2156
2 locks held by syz.5.212/7309:
#0: ffff888035c5a0d0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888035c5a0d0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
#1: ffff88806825e8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline]
#1: ffff88806825e8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c5/0xc10 fs/fs-writeback.c:2922
2 locks held by syz.1.217/7337:
#0: ffff888035c5a0d0 (&type->s_umount_key#62){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff888035c5a0d0 (&type->s_umount_key#62){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
#1: ffff88806825e8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline]
#1: ffff88806825e8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c5/0xc10 fs/fs-writeback.c:2922
7 locks held by syz.8.377/8822:
4 locks held by syz.6.380/8848:
4 locks held by syz.3.382/8851:
2 locks held by syz.9.381/8862:
3 locks held by syz-executor/8863:
4 locks held by udevadm/8885:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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:161 [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+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 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: 8848 Comm: syz.6.380 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:__lru_cache_activate_folio+0x3d9/0x5a0 mm/swap.c:385
Code: de e8 ab 2f c1 ff 85 db 74 5c e8 f2 2a c1 ff eb 19 e8 eb 2a c1 ff 41 ff ce 42 0f b6 04 23 84 c0 0f 85 52 01 00 00 66 45 89 37 <48> 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 be
RSP: 0018:ffffc9001e93f3d8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff110063fb450 RCX: ffff888031fd9e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1e9250f R12: dffffc0000000000
R13: ffff8880b8933d78 R14: 0000000000000001 R15: ffff888031fda280
FS: 0000000000000000(0000) GS:ffff888126695000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e724220 CR3: 000000006642c000 CR4: 00000000003526f0
Call Trace:
folio_mark_accessed+0x288/0x4a0 mm/swap.c:482
zap_present_folio_ptes mm/memory.c:1639 [inline]
zap_present_ptes mm/memory.c:1712 [inline]
do_zap_pte_range mm/memory.c:1814 [inline]
zap_pte_range mm/memory.c:1858 [inline]
zap_pmd_range mm/memory.c:1950 [inline]
zap_pud_range mm/memory.c:1978 [inline]
zap_p4d_range mm/memory.c:1999 [inline]
unmap_page_range+0x16b4/0x3cd0 mm/memory.c:2020
unmap_single_vma mm/memory.c:2062 [inline]
unmap_vmas+0x3c0/0x5c0 mm/memory.c:2104
exit_mmap+0x251/0xb30 mm/mmap.c:1277
__mmput+0xcb/0x3d0 kernel/fork.c:1174
exit_mm+0x168/0x220 kernel/exit.c:581
do_exit+0x62e/0x2320 kernel/exit.c:959
do_group_exit+0x21b/0x2d0 kernel/exit.c:1112
get_signal+0x125c/0x1310 kernel/signal.c:3034
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f46015fbf79
Code: Unable to access opcode bytes at 0x7f46015fbf4f.
RSP: 002b:00007f45ff84e0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f4601875fa8 RCX: 00007f46015fbf79
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4601875fa8
RBP: 00007f4601875fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4601876038 R14: 00007ffeb21cb030 R15: 00007ffeb21cb118