INFO: task udevd:9887 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
io_schedule+0x80/0xe0 kernel/sched/core.c:7835
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit_lock+0xe3/0x4b0 kernel/sched/wait_bit.c:93
out_of_line_wait_on_bit_lock+0x13b/0x190 kernel/sched/wait_bit.c:120
wait_on_bit_lock_io include/linux/wait_bit.h:221 [inline]
__lock_buffer fs/buffer.c:72 [inline]
lock_buffer include/linux/buffer_head.h:432 [inline]
block_read_full_folio+0x38f/0x830 fs/buffer.c:2436
filemap_read_folio+0x137/0x3b0 mm/filemap.c:2501
filemap_update_page mm/filemap.c:2588 [inline]
filemap_get_pages+0x16de/0x1ea0 mm/filemap.c:2718
filemap_read+0x44a/0x1240 mm/filemap.c:2805
blkdev_read_iter+0x311/0x440 block/fops.c:855
new_sync_read fs/read_write.c:493 [inline]
vfs_read+0x58b/0xa80 fs/read_write.c:574
ksys_read+0x156/0x270 fs/read_write.c:717
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff79f23a407
RSP: 002b:00007fff0ae85630 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007ff79f14c880 RCX: 00007ff79f23a407
RDX: 0000000000000200 RSI: 00007ff79e802000 RDI: 0000000000000009
RBP: 000055b28093a050 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 000055b2809545d8 R15: 00007ff79f99039c
INFO: task syz.4.1113:14040 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.1113 state:D stack:24352 pid:14040 tgid:14039 ppid:11496 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
io_schedule+0x80/0xe0 kernel/sched/core.c:7835
folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1323
folio_lock include/linux/pagemap.h:1170 [inline]
__find_get_block_slow fs/buffer.c:206 [inline]
find_get_block_common+0x34f/0xe10 fs/buffer.c:1405
bdev_getblk+0x53/0x6e0 include/linux/gfp.h:-1
__getblk include/linux/buffer_head.h:380 [inline]
sb_getblk include/linux/buffer_head.h:386 [inline]
__ext4_get_inode_loc+0x7d8/0xfa0 fs/ext4/inode.c:4812
ext4_get_inode_loc fs/ext4/inode.c:4915 [inline]
ext4_reserve_inode_write+0x18b/0x360 fs/ext4/inode.c:6235
__ext4_mark_inode_dirty+0x14b/0x730 fs/ext4/inode.c:6413
ext4_evict_inode+0x7a1/0xeb0 fs/ext4/inode.c:255
evict+0x61e/0xb10 fs/inode.c:846
ext4_orphan_cleanup+0xc38/0x1470 fs/ext4/orphan.c:472
__ext4_fill_super fs/ext4/super.c:5668 [inline]
ext4_fill_super+0x5a0b/0x6320 fs/ext4/super.c:5791
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3763 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3839
do_mount fs/namespace.c:4172 [inline]
__do_sys_mount fs/namespace.c:4361 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4338
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa5c4b6da0a
RSP: 002b:00007fa5c2dbde58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fa5c2dbdee0 RCX: 00007fa5c4b6da0a
RDX: 0000200000000140 RSI: 0000200000000040 RDI: 00007fa5c2dbdea0
RBP: 0000200000000140 R08: 00007fa5c2dbdee0 R09: 0000000000000800
R10: 0000000000000800 R11: 0000000000000246 R12: 0000200000000040
R13: 00007fa5c2dbdea0 R14: 00000000000005fc R15: 00002000000000c0
Showing all locks held in the system:
3 locks held by kworker/0:1/10:
#0: ffff888019c07938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff888019c07938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc900000f7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc900000f7c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffff88803c76f260 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x222/0x3e0 drivers/net/netdevsim/fib.c:1490
2 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/38:
#0: ffffffff8ddcba80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcba80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcba80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/u8:5/86:
#0: ffff88801f2a7938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88801f2a7938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc900015efc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc900015efc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffff88801b2840d0 (&type->s_umount_key#43){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
2 locks held by getty/5558:
#0: ffff888037a480a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e7e2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by udevd/9887:
#0: ffff8880226c0930 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline]
#0: ffff8880226c0930 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:854
#1: ffff8880226c0b00 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1093 [inline]
#1: ffff8880226c0b00 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_update_page mm/filemap.c:2554 [inline]
#1: ffff8880226c0b00 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_get_pages+0x931/0x1ea0 mm/filemap.c:2718
1 lock held by udevd/9914:
5 locks held by udevd/10439:
2 locks held by syz.4.1113/14040:
#0: ffff88803634a0d0 (&type->s_umount_key#29/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
#1: ffff88803634a770 (sb_internal){++++}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
#1: ffff88803634a770 (sb_internal){++++}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline]
#1: ffff88803634a770 (sb_internal){++++}-{0:0}, at: sb_start_intwrite include/linux/fs/super.h:177 [inline]
#1: ffff88803634a770 (sb_internal){++++}-{0:0}, at: ext4_evict_inode+0x274/0xeb0 fs/ext4/inode.c:216
2 locks held by udevd/16128:
1 lock held by syz-executor/17320:
1 lock held by syz.1.1326/17806:
2 locks held by syz.6.1327/17810:
1 lock held by sed/17812:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 9914 Comm: udevd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:-1 [inline]
RIP: 0010:rcu_is_watching+0x44/0xb0 kernel/rcu/tree.c:752
Code: 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 90 57 80 8d 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 9c 1b 81 00 <48> c7 c3 98 af 4f 92 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38
RSP: 0018:ffffc90004767038 EFLAGS: 00000246
RAX: 1ffffffff1b00af3 RBX: 0000000000000001 RCX: 0000000080000001
RDX: ffffc90004767101 RSI: ffffffff8ba671e0 RDI: ffffffff8ba671a0
RBP: dffffc0000000000 R08: ffffc900047675d0 R09: 0000000000000000
R10: ffffc90004767178 R11: fffff520008ece31 R12: ffffc900047675e0
R13: ffffc90004760000 R14: ffffffff8d805798 R15: dffffc0000000000
FS: 00007ff79f14c880(0000) GS:ffff888126439000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1e071854e8 CR3: 000000003b536000 CR4: 00000000003526f0
Call Trace:
rcu_read_unlock include/linux/rcupdate.h:879 [inline]
class_rcu_destructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0x1a66/0x23c0 arch/x86/kernel/unwind_orc.c:695
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5260 [inline]
__kmalloc_noprof+0x3e7/0x7b0 mm/slub.c:5272
kmalloc_noprof include/linux/slab.h:954 [inline]
tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776
security_file_open+0xa9/0x240 security/security.c:2636
do_dentry_open+0x4c0/0x13e0 fs/open.c:926
vfs_open+0x3b/0x350 fs/open.c:1081
do_open fs/namei.c:4671 [inline]
path_openat+0x2e43/0x38a0 fs/namei.c:4830
do_file_open+0x23e/0x4a0 fs/namei.c:4859
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff79f23a407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fff0ae8a1b0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ff79f14c880 RCX: 00007ff79f23a407
RDX: 0000000000080241 RSI: 00007fff0ae8a710 RDI: ffffffffffffff9c
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001b6 R11: 0000000000000202 R12: 000055b2532f8dfc
R13: 000055b2532f8dfc R14: 0000000000000001 R15: 000055b280940ba0