INFO: task kworker/u4:2:150 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:2 state:D stack:24928 pid: 150 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+0x360/0xb90 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.0.15:5279 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:24448 pid: 5279 ppid: 5003 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+0x1eca/0x43c0 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:ffffc9000316f6a0 EFLAGS: 00050202
RAX: ffffffff83dadb01 RBX: 0000000000000038 RCX: 0000000000000007
RDX: 0000000000000000 RSI: ffffc9000316f740 RDI: 00000000200058e0
RBP: 0000000000000000 R08: 0000000000000000 R09: fffff5200062deef
R10: fffff5200062deef R11: 1ffff9200062dee8 R12: 00007ffffffff000
R13: 0000000020005918 R14: ffffc9000316f740 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:5447 [inline]
extent_fiemap+0x1055/0x14f0 fs/btrfs/extent_io.c:5686
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: 0033:0x7f0bc0b2fff9
RSP: 002b:00007f0bbfdb0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f0bc0ce7f80 RCX: 00007f0bc0b2fff9
RDX: 00000000200058c0 RSI: 00000000c020660b RDI: 0000000000000004
RBP: 00007f0bc0ba2296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0bc0ce7f80 R15: 00007ffedba95c08
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:2/150:
#0: ffff88807ba53938 ((wq_completion)btrfs-endio-write){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000171fd00 ((work_completion)(&work->normal_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
3 locks held by kworker/1:2/1108:
2 locks held by getty/3951:
#0: ffff88802bd24098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
3 locks held by syz.0.15/5279:
#0: ffff888073a4e328 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
#0: ffff888073a4e328 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x2b9/0xc80 arch/x86/mm/fault.c:1298
#1: ffff888079042558 (sb_pagefaults#2){.+.+}-{0:0}, at: do_page_mkwrite+0x168/0x3c0 mm/memory.c:2922
#2: ffff88806ff38498 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_page_mkwrite+0x461/0xc50 fs/btrfs/inode.c:8965
2 locks held by udevd/5305:
=============================================
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 07/12/2025
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: 7031 Comm: syz.0.580 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:trace_hardirqs_on+0x0/0x80 kernel/trace/trace_preemptirq.c:41
Code: ff e9 94 fe ff ff e8 ef e1 f9 ff 0f 0b e9 39 ff ff ff e8 e3 e1 f9 ff e8 56 91 82 ff e9 79 fe ff ff 66 0f 1f 84 00 00 00 00 00 <53> e8 ca e1 f9 ff 65 8b 1d 9b 49 85 7e 31 ff 89 de e8 1a e5 f9 ff
RSP: 0018:ffffc9000352f6d8 EFLAGS: 00000006
RAX: 0000000000000000 RBX: ffff888078218000 RCX: cbd5e012fb182300
RDX: 0000000000000000 RSI: ffffffff8a59a460 RDI: ffffffff8a59a420
RBP: ffffc9000352f8d0 R08: dffffc0000000000 R09: fffff940003460e1
R10: fffff940003460e1 R11: 1ffffd40003460e0 R12: 0000000000000287
R13: 1ffff11017226c93 R14: ffff8880b9136401 R15: dffffc0000000000
FS: 00007fbaabd446c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f25ffff CR3: 000000001ea8e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
consume_stock mm/memcontrol.c:2212 [inline]
try_charge_memcg+0x1ee/0x14a0 mm/memcontrol.c:2607
try_charge mm/memcontrol.c:2779 [inline]
charge_memcg+0x100/0x2e0 mm/memcontrol.c:6765
__mem_cgroup_charge+0x21/0x80 mm/memcontrol.c:6801
mem_cgroup_charge include/linux/memcontrol.h:700 [inline]
shmem_add_to_page_cache+0xa83/0x14b0 mm/shmem.c:718
shmem_getpage_gfp+0x1793/0x2d40 mm/shmem.c:1940
shmem_getpage mm/shmem.c:151 [inline]
shmem_fallocate+0x7de/0xe20 mm/shmem.c:2758
vfs_fallocate+0x587/0x6f0 fs/open.c:308
ksys_fallocate fs/open.c:331 [inline]
__do_sys_fallocate fs/open.c:339 [inline]
__se_sys_fallocate fs/open.c:337 [inline]
__x64_sys_fallocate+0xbd/0x100 fs/open.c:337
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: 0033:0x7fbaacac3ff9
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:00007fbaabd44038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007fbaacc7bf80 RCX: 00007fbaacac3ff9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fbaacb36296 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000001000f4 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbaacc7bf80 R15: 00007ffdfbfc9cb8