INFO: task syz.0.1039:9815 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1039 state:D stack:26008 pid:9815 tgid:9813 ppid:5613 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x125e/0x6990 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7474
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7531
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xcca/0x1c10 kernel/locking/mutex.c:821
sync_bdevs+0x153/0x480 block/bdev.c:1369
ksys_sync+0xb0/0xf0 fs/sync.c:105
__do_sys_sync+0xe/0x20 fs/sync.c:111
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe11f79f559
RSP: 002b:00007fe120666028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fe11fa26090 RCX: 00007fe11f79f559
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fe11fa26090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe11fa26128 R14: 00007fe11fa26090 R15: 00007ffe251d86b8
Showing all locks held in the system:
locks held by khungtaskd/32: 1, last CPU#0:
#0: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6871
locks held by getty/5373: 2, on CPU#0:
#0: ffff88803a0f40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900032362e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1540 drivers/tty/n_tty.c:2211
locks held by syz-executor/5614: 1, last CPU#0:
#0: ffff88807bb56460 (sb_writers#6){.+.+}-{0:0}, at: filename_unlinkat+0x1ad/0x730 fs/namei.c:5708
locks held by syz-executor/5615: 2, last CPU#1:
#0: ffff88802d4bc460 (sb_writers#6){.+.+}-{0:0}, at: filename_unlinkat+0x1ad/0x730 fs/namei.c:5708
#1: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#1: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
locks held by udevd/8986: 1, on CPU#0:
#0: ffff88802986c350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x426/0xe50 block/bdev.c:990
locks held by udevd/9126: 1, on CPU#0:
#0: ffff888029a18350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x426/0xe50 block/bdev.c:990
locks held by syz.0.1039/9815: 1, on CPU#1:
#0: ffff88802986c350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1369
locks held by syz-executor/10003: 1, last CPU#0:
#0: ffff88807b93a460 (sb_writers#6){.+.+}-{0:0}, at: filename_unlinkat+0x1ad/0x730 fs/namei.c:5708
locks held by syz.4.1497/11585: 1, last CPU#1:
#0: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: folio_lruvec_lock_irqsave+0x2c/0x5e0 mm/memcontrol.c:1541
locks held by iou-sqp-11676/11677: 1, last CPU#1:
#0: ffff888069596468 (&sqd->lock){+.+.}-{4:4}, at: io_sq_thread+0xddc/0x14b0 io_uring/sqpoll.c:363
locks held by syz.1.1536/11685: 2, last CPU#1:
#0: ffff888039f141c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:337
#1: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8ffeb4e0 (rcu_read_lock){....}-{1:3}, at: count_memcg_events_mm.constprop.0+0x2f/0x2a0 include/linux/memcontrol.h:1020
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x21f/0x2a0 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:377 [inline]
watchdog+0xd0f/0x10c0 kernel/hung_task.c:598
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
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: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 47 a3 02 e9 43 61 03 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d c3 dd 1f 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197e00 EFLAGS: 00000242
RAX: 00000000025a8737 RBX: ffff88801fada580 RCX: ffffffff8bebe325
RDX: 0000000000000001 RSI: ffffffff8e621faf RDI: ffffffff8c833580
RBP: ffffed1003f5b4b0 R08: 0000000000000001 R09: ffffed1017026825
R10: ffff8880b813412b R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 1ffff92000032fc4 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff88812258e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32520000 CR3: 000000005c8bb000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
default_idle+0x9/0x10 arch/x86/kernel/process.c:768
default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x3ae/0x5b0 kernel/sched/idle.c:355
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x158