INFO: task udevd:16489 blocked in I/O wait for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:23976 pid:16489 tgid:16489 ppid:4978   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d4/0x5630 kernel/sched/core.c:7239
 __schedule_loop kernel/sched/core.c:7316 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7331
 io_schedule+0x7f/0xd0 kernel/sched/core.c:8159
 folio_wait_bit_common+0x836/0xbc0 mm/filemap.c:1329
 folio_put_wait_locked mm/filemap.c:1498 [inline]
 do_read_cache_folio+0x1ac/0x590 mm/filemap.c:4128
 read_mapping_folio include/linux/pagemap.h:1015 [inline]
 read_part_sector+0xb6/0x2b0 block/partitions/core.c:724
 adfspart_check_POWERTEC+0x9a/0x7a0 block/partitions/acorn.c:451
 check_partition block/partitions/core.c:143 [inline]
 blk_add_partitions block/partitions/core.c:591 [inline]
 bdev_disk_changed+0x851/0x17a0 block/partitions/core.c:695
 blkdev_get_whole+0x372/0x510 block/bdev.c:794
 bdev_open+0x324/0xd70 block/bdev.c:1003
 blkdev_open+0x461/0x600 block/fops.c:674
 do_dentry_open+0x816/0x1380 fs/open.c:996
 vfs_open+0x3b/0x340 fs/open.c:1101
 do_open fs/namei.c:4837 [inline]
 path_openat+0x1443/0x1d60 fs/namei.c:5000
 do_file_open+0x23e/0x4a0 fs/namei.c:5029
 do_sys_openat2+0x115/0x200 fs/open.c:1417
 do_sys_open fs/open.c:1423 [inline]
 __do_sys_openat fs/open.c:1439 [inline]
 __se_sys_openat fs/open.c:1434 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1434
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f002f8a7407
RSP: 002b:00007fff3acf5260 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0030043880 RCX: 00007f002f8a7407
RDX: 00000000000a0800 RSI: 00005618b25d8520 RDI: ffffffffffffff9c
RBP: 00005618b25d7910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005618b25ebba0
R13: 00005618b25e5190 R14: 0000000000000000 R15: 00005618b25ebba0
 </TASK>

Showing all locks held in the system:
locks held by khungtaskd/30: 1, last CPU#1:
 #0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6793
locks held by getty/5369: 2, on CPU#1:
 #0: ffff88803651b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by udevd/16489: 1, on CPU#1:
 #0: ffff888026376350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:991
locks held by udevd/17655: 1, last CPU#1:
 #0: ffff8880b873b4e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
locks held by syz.9.5168/29401: 1, on CPU#0:
 #0: ffffffff8eb603b8 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3857
locks held by syz.8.5170/29409: 1, last CPU#0:
 #0: ffff88807bf3b6b8 (&mm->mmap_lock){++++}-{4:4}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff88807bf3b6b8 (&mm->mmap_lock){++++}-{4:4}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffff88807bf3b6b8 (&mm->mmap_lock){++++}-{4:4}, at: bpf_map_update_value+0x644/0x920 kernel/bpf/syscall.c:296
locks held by syz.0.5172/29419: 2, last CPU#0:
 #0: ffff8880b863b4e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
 #1: ffff8880b8624408 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933
locks held by syz.0.5172/29420: 2, on CPU#0:
 #0: ffff88807adcbcd0 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x3b/0x100 net/netfilter/nf_tables_api.c:11512
 #1: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
 #1: ffffffff8eb604e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
 nmi_trigger_cpumask_backtrace+0x17d/0x390 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+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+0x38b/0x480 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 29405 Comm: syz.9.5168 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:__folio_mod_stat mm/rmap.c:1334 [inline]
RIP: 0010:__folio_remove_rmap mm/rmap.c:1873 [inline]
RIP: 0010:folio_remove_rmap_ptes+0x569/0xe40 mm/rmap.c:1900
Code: 2d e1 a3 ff 41 39 ef 0f 88 90 00 00 00 e8 1f dc a3 ff 49 bf 00 00 00 00 00 fc ff df 4c 8d 6b 68 4c 8b 74 24 08 e9 58 01 00 00 <e8> 02 dc a3 ff e9 f3 02 00 00 e8 f8 db a3 ff 49 bf 00 00 00 00 00
RSP: 0018:ffffc9000fa7f328 EFLAGS: 00000202
RAX: ffffffff82232ed1 RBX: ffffea00016a3e00 RCX: ffff888040640000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffea00016a3e33 R09: 1ffffd40002d47c6
R10: dffffc0000000000 R11: fffff940002d47c7 R12: ffffea00016a3e00
R13: dffffc0000000000 R14: 0000000000000001 R15: ffffea00016a3e30
FS:  0000000000000000(0000) GS:ffff888124f24000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000081000 CR3: 0000000079e5c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 zap_present_folio_ptes mm/memory.c:1672 [inline]
 zap_present_ptes mm/memory.c:1730 [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+0x22ff/0x4f20 mm/memory.c:2109
 unmap_vmas+0x390/0x550 mm/memory.c:2178
 exit_mmap+0x293/0x9f0 mm/mmap.c:1300
 __mmput+0x118/0x420 kernel/fork.c:1193
 exit_mm+0x221/0x2d0 kernel/exit.c:615
 do_exit+0x6cd/0x2360 kernel/exit.c:997
 do_group_exit+0x22d/0x2f0 kernel/exit.c:1152
 get_signal+0x121b/0x12c0 kernel/signal.c:3046
 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:336 [inline]
 do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8478b9e0d9
Code: Unable to access opcode bytes at 0x7f8478b9e0af.
RSP: 002b:00007f8479b440e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f8478e25fa8 RCX: 00007f8478b9e0d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f8478e25fa8
RBP: 00007f8478e25fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8478e26038 R14: 00007fff768846f0 R15: 00007fff768847d8
 </TASK>