INFO: task kworker/u8:12:2277 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:12 state:D stack:21832 pid:2277 tgid:2277 ppid:2 [ 312.818414][ T37] task:kworker/u8:12 state:D stack:21832 pid:2277 tgid:2277 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7228
__schedule_loop kernel/sched/core.c:7307 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7603
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1670 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
__rt_mutex_slowlock_locked+0x1f84/0x25b0 kernel/locking/rtmutex.c:1787
rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1827
__rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
rwbase_write_lock+0x14c/0x720 kernel/locking/rwbase_rt.c:251
f2fs_down_write fs/f2fs/f2fs.h:2411 [inline]
f2fs_down_write_trace+0x34/0x1f0 fs/f2fs/checkpoint.c:180
f2fs_issue_checkpoint+0x414/0x6f0 fs/f2fs/checkpoint.c:2095
f2fs_balance_fs_bg+0x571/0x9d0 fs/f2fs/segment.c:545
f2fs_write_node_pages+0x158/0x700 fs/f2fs/node.c:2257
do_writepages+0x338/0x560 mm/page-writeback.c:2571
__writeback_single_inode+0x12e/0xf90 fs/fs-writeback.c:1787
writeback_sb_inodes+0x9db/0x1ab0 fs/fs-writeback.c:2079
__writeback_inodes_wb+0x114/0x240 fs/fs-writeback.c:2155
wb_writeback+0x42f/0xad0 fs/fs-writeback.c:2266
wb_check_old_data_flush fs/fs-writeback.c:2370 [inline]
wb_do_writeback fs/fs-writeback.c:2449 [inline]
wb_workfn+0xc98/0x10f0 fs/fs-writeback.c:2477
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 10811 Comm: syz.5.492 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x2a/0xa0 kernel/kcov.c:314
Code: f3 0f 1e fa 48 8b 04 24 65 48 8b 0d b8 e3 a8 10 65 44 8b 05 d8 e3 a8 10 41 81 e0 00 00 ff 00 ba 00 01 00 00 23 91 f4 0b 00 00 <41> 89 d1 45 09 c1 74 12 45 85 c0 75 5f 85 d2 74 5b 83 b9 0c 17 00
RSP: 0018:ffffc900060c7290 EFLAGS: 00000246
RAX: ffffffff82356cd2 RBX: ffff88801a580000 RCX: ffff88803ac63e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed10049b5ad6 R12: 000000000000b594
R13: dffffc0000000000 R14: ffff88813fe44030 R15: 0000000000001000
FS: 00007f774144e6c0(0000) GS:ffff888126142000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f48ea76da08 CR3: 000000003c76e000 CR4: 00000000003526f0
Call Trace:
lookup_page_ext mm/page_ext.c:258 [inline]
page_ext_lookup+0xf2/0x180 mm/page_ext.c:513
page_ext_iter_begin include/linux/page_ext.h:133 [inline]
page_table_check_clear+0x212/0x4f0 mm/page_table_check.c:78
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
zap_present_ptes mm/memory.c:1703 [inline]
do_zap_pte_range mm/memory.c:1832 [inline]
zap_pte_range mm/memory.c:1934 [inline]
zap_pmd_range mm/memory.c:2020 [inline]
zap_pud_range mm/memory.c:2048 [inline]
zap_p4d_range mm/memory.c:2069 [inline]
__zap_vma_range+0x3456/0x49e0 mm/memory.c:2109
unmap_vmas+0x390/0x550 mm/memory.c:2178
unmap_region+0x208/0x330 mm/vma.c:488
vms_clear_ptes mm/vma.c:1303 [inline]
vms_complete_munmap_vmas+0x427/0xbe0 mm/vma.c:1345
do_vmi_align_munmap+0x3bd/0x4d0 mm/vma.c:1604
do_vmi_munmap+0x252/0x2d0 mm/vma.c:1652
__vm_munmap+0x241/0x3e0 mm/vma.c:3288
__do_sys_munmap mm/mmap.c:1079 [inline]
__se_sys_munmap mm/mmap.c:1076 [inline]
__x64_sys_munmap+0x60/0x70 mm/mmap.c:1076
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f77431fcc87
Code: 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f774144de08 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f77431fcc87
RDX: 0000000001000000 RSI: 0000000008400000 RDI: 00007f773902e000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f774144dee0 R14: 00007f774144dea0 R15: 00007f773902e000