INFO: task syz.2.975:10402 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.975 state:D stack:27336 pid:10402 ppid:9530 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747
sync_bdevs+0x1af/0x330 block/bdev.c:1076
ksys_sync+0xba/0x150 fs/sync.c:105
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa30d78f749
RSP: 002b:00007fa30e5d4038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fa30d9e6180 RCX: 00007fa30d78f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa30d9e6180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa30d9e6218 R14: 00007fa30d9e6180 R15: 00007ffeb14ca9a8
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/u4:7/1032:
2 locks held by kworker/u4:10/1140:
2 locks held by getty/5532:
#0: ffff8880311a20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000328b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
1 lock held by udevd/5784:
#0: ffff8880212474c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x121/0x600 block/bdev.c:805
2 locks held by udevd/5918:
1 lock held by syz-executor/8152:
1 lock held by syz.2.975/10402:
#0: ffff8880212474c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1af/0x330 block/bdev.c:1076
1 lock held by syz.7.1608/12266:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf41/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12275 Comm: syz.5.1606 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x30/0x90 kernel/kcov.c:299
Code: 04 24 65 48 8b 15 20 08 7e 7e 65 8b 0d 21 08 7e 7e 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 1c 16 00 00 00 74 52 <8b> 8a f8 15 00 00 83 f9 03 75 47 48 8b 8a 00 16 00 00 44 8b 8a fc
RSP: 0018:ffffc9001354f178 EFLAGS: 00000046
RAX: ffffffff8a5aac4e RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888041f4bc00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffea0001596647 R09: 1ffffd40002b2cc8
R10: dffffc0000000000 R11: fffff940002b2cc9 R12: ffffc9001354f2b1
R13: 1ffff920026a9e56 R14: ffffc9001354f2a0 R15: ffffc9001354f2b2
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f20a9784f98 CR3: 000000000cb30000 CR4: 00000000003506e0
Call Trace:
xas_store+0x3de/0x19e0 lib/xarray.c:805
page_cache_delete mm/filemap.c:142 [inline]
__filemap_remove_folio+0x44f/0x7f0 mm/filemap.c:225
filemap_remove_folio+0xf1/0x2c0 mm/filemap.c:257
truncate_inode_folio+0x5d/0x70 mm/truncate.c:195
shmem_undo_range+0x3b9/0x1a40 mm/shmem.c:1022
shmem_truncate_range mm/shmem.c:1135 [inline]
shmem_evict_inode+0x273/0xa70 mm/shmem.c:1264
evict+0x486/0x870 fs/inode.c:705
__dentry_kill+0x431/0x650 fs/dcache.c:611
dentry_kill+0xb8/0x290 fs/dcache.c:-1
dput+0xfe/0x1e0 fs/dcache.c:918
__fput+0x5e5/0x970 fs/file_table.c:392
task_work_run+0x1ce/0x250 kernel/task_work.c:245
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x90b/0x23c0 kernel/exit.c:883
do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
get_signal+0x12fc/0x1400 kernel/signal.c:2902
arch_do_signal_or_restart+0x9c/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f20a898f749
Code: Unable to access opcode bytes at 0x7f20a898f71f.
RSP: 002b:00007f20a9785038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000010106 RBX: 00007f20a8be6090 RCX: 00007f20a898f749
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000006
RBP: 00007f20a8a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f20a8be6128 R14: 00007f20a8be6090 R15: 00007ffce759d2b8