INFO: task syz.3.1398:11276 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1398 state:D stack:28216 pid:11276 tgid:11275 ppid:5805 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0xfe6/0x5fa0 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:6964
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776
sync_bdevs+0x153/0x480 block/bdev.c:1305
ksys_sync+0xb2/0x150 fs/sync.c:105
__do_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1300b9aeb9
RSP: 002b:00007f1301aee028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f1300e15fa0 RCX: 00007f1300b9aeb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f1300e15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1300e16038 R14: 00007f1300e15fa0 R15: 00007ffda8761fc8
Showing all locks held in the system:
1 lock held by ksoftirqd/1/23:
#0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline]
#0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632
1 lock held by khungtaskd/31:
#0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/5566:
#0: ffff88814d1fa0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5811:
#0: ffffffff8e5efab8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
1 lock held by udevd/10384:
#0: ffff888026a0f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:962
1 lock held by syz.3.1398/11276:
#0: ffff888026a0f358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1305
1 lock held by syz.1.1998/13438:
3 locks held by syz.1.2007/13460:
1 lock held by syz.4.2012/13475:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [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:346 [inline]
watchdog+0xcc3/0xfe0 kernel/hung_task.c:515
kthread+0x3b3/0x730 kernel/kthread.c:463
ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 13482 Comm: syz.0.2014 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:417
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 e9 2b a7 fb f5 cc
RSP: 0018:ffffc90002e86618 EFLAGS: 00000286
RAX: 0000000000000001 RBX: 000000000004c642 RCX: 0000000000000001
RDX: 0000000000000046 RSI: ffffffff8dc20053 RDI: ffffffff8bfa38a0
RBP: ffff88801c580000 R08: 0000000000000006 R09: 0000000000001000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: 1ffff920005d0cdf R14: 00000000062c059c R15: 0000000000000000
FS: 00007f5c7cc276c0(0000) GS:ffff8881246d9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c331c27 CR3: 000000007c497000 CR4: 00000000003526f0
Call Trace:
lookup_page_ext+0x6e/0x100 mm/page_ext.c:254
page_ext_iter_begin include/linux/page_ext.h:132 [inline]
__update_page_owner_handle+0xcb/0x550 mm/page_owner.c:256
__set_page_owner+0x11f/0x540 mm/page_owner.c:342
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x1e1/0x250 mm/page_alloc.c:1884
prep_new_page mm/page_alloc.c:1892 [inline]
get_page_from_freelist+0xe3d/0x2e10 mm/page_alloc.c:3945
__alloc_frozen_pages_noprof+0x26c/0x2410 mm/page_alloc.c:5240
alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486
folio_alloc_mpol_noprof+0x36/0x340 mm/mempolicy.c:2505
shmem_alloc_folio+0x135/0x160 mm/shmem.c:1918
shmem_alloc_and_add_folio+0x371/0xd40 mm/shmem.c:1960
shmem_get_folio_gfp+0x6ab/0x1900 mm/shmem.c:2584
shmem_fault+0x1f9/0xa20 mm/shmem.c:2785
__do_fault+0x10d/0x550 mm/memory.c:5323
do_shared_fault mm/memory.c:5822 [inline]
do_fault+0x2db/0x1990 mm/memory.c:5896
do_pte_missing mm/memory.c:4404 [inline]
handle_pte_fault mm/memory.c:6276 [inline]
__handle_mm_fault+0x1807/0x2b50 mm/memory.c:6414
handle_mm_fault+0x36d/0xa20 mm/memory.c:6583
faultin_page mm/gup.c:1126 [inline]
__get_user_pages+0xf9c/0x34d0 mm/gup.c:1428
__get_user_pages_locked mm/gup.c:1692 [inline]
__gup_longterm_locked+0x279/0x16f0 mm/gup.c:2481
gup_fast_fallback+0x18c6/0x2460 mm/gup.c:3220
pin_user_pages_fast+0xa7/0xf0 mm/gup.c:3326
pfn_reader_user_pin+0xd01/0x10f0 drivers/iommu/iommufd/pages.c:932
iopt_pages_fill drivers/iommu/iommufd/pages.c:2149 [inline]
iopt_pages_fill_xarray+0x494/0xdd0 drivers/iommu/iommufd/pages.c:2216
iopt_area_add_access+0x22a/0x410 drivers/iommu/iommufd/pages.c:2464
iommufd_access_pin_pages+0x649/0xa10 drivers/iommu/iommufd/device.c:1455
iommufd_test_access_pages drivers/iommu/iommufd/selftest.c:1611 [inline]
iommufd_test+0x4631/0x6610 drivers/iommu/iommufd/selftest.c:2131
iommufd_fops_ioctl+0x358/0x520 drivers/iommu/iommufd/main.c:533
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5c7bd9aeb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5c7cc27028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5c7c015fa0 RCX: 00007f5c7bd9aeb9
RDX: 0000200000000100 RSI: 0000000000003ba0 RDI: 0000000000000004
RBP: 00007f5c7be08c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5c7c016038 R14: 00007f5c7c015fa0 R15: 00007fff9776d618