INFO: task syz.0.1940:12565 blocked for more than 143 seconds.
Not tainted 6.17.0-rc2-next-20250818-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1940 state:D stack:24552 pid:12565 tgid:12563 ppid:5857 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
request_wait_answer fs/fuse/dev.c:566 [inline]
__fuse_request_send fs/fuse/dev.c:580 [inline]
__fuse_simple_request+0xf15/0x18d0 fs/fuse/dev.c:674
fuse_simple_request fs/fuse/fuse_i.h:1230 [inline]
fuse_flush+0x5d4/0x800 fs/fuse/file.c:476
filp_flush+0xba/0x190 fs/open.c:1547
filp_close+0x1d/0x40 fs/open.c:1560
__range_close fs/file.c:767 [inline]
__do_sys_close_range fs/file.c:826 [inline]
__se_sys_close_range+0x359/0x650 fs/file.c:790
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f84c4b8ebe9
RSP: 002b:00007f84c593b038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007f84c4db6090 RCX: 00007f84c4b8ebe9
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000000
RBP: 00007f84c4c11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f84c4db6128 R14: 00007f84c4db6090 R15: 00007ffe6e73fd68
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.17.0-rc2-next-20250818-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 13691 Comm: syz.5.2243 Not tainted 6.17.0-rc2-next-20250818-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x37/0x90 kernel/kcov.c:321
Code: 08 00 e5 92 65 8b 15 68 04 25 11 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 3c 16 00 00 00 74 4e 8b 91 18 16 00 00 <83> fa 03 75 43 48 8b 91 20 16 00 00 44 8b 89 1c 16 00 00 49 c1 e1
RSP: 0018:ffffc90004d47800 EFLAGS: 00000246
RAX: ffffffff822d1692 RBX: dffffc0000000000 RCX: ffff88802a385a00
RDX: 0000000000000000 RSI: 00000000000020b7 RDI: 0000000000000000
RBP: ffff88801e8a3924 R08: ffff88801e8a38e7 R09: 1ffff11003d1471c
R10: dffffc0000000000 R11: ffffed1003d1471d R12: 000000000007a0b7
R13: 000000000000357b R14: 0000000000000000 R15: 000000000007a0b7
FS: 0000000000000000(0000) GS:ffff8881258d0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f03e4d909c0 CR3: 000000000e336000 CR4: 00000000003526f0
Call Trace:
page_ext_iter_next_fast_possible include/linux/page_ext.h:80 [inline]
page_ext_iter_next include/linux/page_ext.h:155 [inline]
__update_page_owner_free_handle+0x292/0x470 mm/page_owner.c:272
__reset_page_owner+0x85/0x1f0 mm/page_owner.c:309
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1395 [inline]
__free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895
vfree+0x25a/0x400 mm/vmalloc.c:3434
kcov_put kernel/kcov.c:439 [inline]
kcov_close+0x28/0x50 kernel/kcov.c:535
__fput+0x449/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x2300 kernel/exit.c:961
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x130 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc4447c14a5
Code: Unable to access opcode bytes at 0x7fc4447c147b.
RSP: 002b:00007fc4429f5f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007fc4449b5fa0 RCX: 00007fc4447c14a5
RDX: 00007fc4429f5fc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fc444811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007fc4449b6038 R14: 00007fc4449b5fa0 R15: 00007fff0f293848