INFO: task kworker/u4:3:155 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:3 state:D stack:24640 pid: 155 ppid: 2 flags:0x00004000
Workqueue: btrfs-endio-write btrfs_work_helper
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
wait_on_state fs/btrfs/extent_io.c:868 [inline]
wait_extent_bit+0x39b/0x4d0 fs/btrfs/extent_io.c:906
lock_extent_bits+0x82/0x110 fs/btrfs/extent_io.c:1469
btrfs_finish_ordered_io+0x5dc/0x1b10 fs/btrfs/inode.c:3108
btrfs_work_helper+0x354/0xb80 fs/btrfs/async-thread.c:325
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
INFO: task syz.0.15:5084 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.15 state:D stack:23968 pid: 5084 ppid: 4801 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
wait_on_state fs/btrfs/extent_io.c:868 [inline]
wait_extent_bit+0x39b/0x4d0 fs/btrfs/extent_io.c:906
lock_extent_bits+0x82/0x110 fs/btrfs/extent_io.c:1469
btrfs_page_mkwrite+0x5b1/0xc50 fs/btrfs/inode.c:8976
do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922
wp_page_shared+0x16b/0x6d0 mm/memory.c:3259
handle_pte_fault mm/memory.c:4668 [inline]
__handle_mm_fault mm/memory.c:4785 [inline]
handle_mm_fault+0x1ec7/0x43b0 mm/memory.c:4883
do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357
handle_page_fault arch/x86/mm/fault.c:1445 [inline]
exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0010:copy_user_generic_unrolled+0x89/0xc0 arch/x86/lib/copy_user_64.S:92
Code: 38 4c 89 47 20 4c 89 4f 28 4c 89 57 30 4c 89 5f 38 48 8d 76 40 48 8d 7f 40 ff c9 75 b6 89 d1 83 e2 07 c1 e9 03 74 12 4c 8b 06 <4c> 89 07 48 8d 76 08 48 8d 7f 08 ff c9 75 ee 21 d2 74 10 89 d1 8a
RSP: 0018:ffffc9000310f6a0 EFLAGS: 00050202
RAX: ffffffff83daee01 RBX: 0000000000000038 RCX: 0000000000000007
RDX: 0000000000000000 RSI: ffffc9000310f740 RDI: 00000000200058e0
RBP: 0000000000000000 R08: 0000000000000000 R09: fffff52000621eef
R10: fffff52000621eef R11: 1ffff92000621ee8 R12: 00007ffffffff000
R13: 0000000020005918 R14: ffffc9000310f740 R15: 00000000200058e0
copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline]
_copy_to_user+0xf0/0x130 lib/usercopy.c:40
copy_to_user include/linux/uaccess.h:200 [inline]
fiemap_fill_next_extent+0x19d/0x360 fs/ioctl.c:144
emit_fiemap_extent fs/btrfs/extent_io.c:5455 [inline]
extent_fiemap+0x1055/0x14f0 fs/btrfs/extent_io.c:5694
btrfs_fiemap+0xc0/0x110 fs/btrfs/inode.c:8599
ioctl_fiemap fs/ioctl.c:219 [inline]
do_vfs_ioctl+0x1464/0x1de0 fs/ioctl.c:814
__do_sys_ioctl fs/ioctl.c:872 [inline]
__se_sys_ioctl+0x83/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0704e77ff9
RSP: 002b:00007f07040f8038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f070502ff80 RCX: 00007f0704e77ff9
RDX: 00000000200058c0 RSI: 00000000c020660b RDI: 0000000000000004
RBP: 00007f0704eea296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f070502ff80 R15: 00007ffcf6c634b8
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:3/155:
#0: ffff88802badf938 ((wq_completion)btrfs-endio-write){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90002087d00 ((work_completion)(&work->normal_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
2 locks held by getty/3941:
#0: ffff88814ce0e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900025ce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
3 locks held by syz.0.15/5084:
#0: ffff8880199ef828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff8880199ef828 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
#1: ffff88807687c558 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922
#2: ffff88805ea78e68 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_page_mkwrite+0x461/0xc50 fs/btrfs/inode.c:8965
1 lock held by udevadm/6816:
2 locks held by syz.0.575/6818:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6818 Comm: syz.0.575 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__lock_acquire+0xdc9/0x7c60 kernel/locking/lockdep.c:4982
Code: 48 89 cb 48 8d 3c c5 c0 e0 fb 8f be 08 00 00 00 e8 ec 28 60 00 49 b8 00 00 00 00 00 fc ff df 48 63 c3 48 0f a3 05 d7 d3 9f 0e <0f> 83 23 4f 00 00 49 8d 9d e0 0a 00 00 49 89 de 49 c1 ee 03 43 80
RSP: 0018:ffffc9000367f3c0 EFLAGS: 00000057
RAX: 00000000000002c2 RBX: 00000000000002c2 RCX: ffffffff815c0cd4
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffbe118
RBP: ffffc9000367f610 R08: dffffc0000000000 R09: fffffbfff1ff7c24
R10: fffffbfff1ff7c24 R11: 1ffffffff1ff7c23 R12: ffff88807470c690
R13: ffff88807470bb80 R14: 0000000000000000 R15: ffff88807470c670
FS: 00007fe451ca16c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcf63b34000 CR3: 0000000073aae000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline]
_raw_spin_lock_irq+0x9f/0xe0 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:389 [inline]
delete_from_page_cache+0x117/0x190 mm/filemap.c:265
truncate_inode_page+0x8d/0xb0 mm/truncate.c:219
shmem_undo_range+0x4dc/0x1880 mm/shmem.c:960
shmem_truncate_range mm/shmem.c:1063 [inline]
shmem_evict_inode+0x20d/0xa00 mm/shmem.c:1145
evict+0x485/0x870 fs/inode.c:647
__dentry_kill+0x431/0x650 fs/dcache.c:586
dentry_kill+0xb8/0x290 fs/dcache.c:-1
dput+0xd8/0x1a0 fs/dcache.c:893
__fput+0x5ee/0x930 fs/file_table.c:319
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fe452a1fc8a
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 13 8c 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 73 8c 02 00 8b 44 24
RSP: 002b:00007fe451ca0e00 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007fe452a1fc8a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000010 R08: 0000000000000000 R09: 00000000000050ed
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 00007fe451ca0ef0 R14: 00007fe451ca1668 R15: 00007fe449881000