INFO: task syz.0.10484:5594 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.0.10484     state:D stack:28056 pid:5594  tgid:5593  ppid:1440   task_flags:0x400140 flags:0x00080002
Call Trace:
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x1709/0x5530 kernel/sched/core.c:7231
 __schedule_loop kernel/sched/core.c:7308 [inline]
 rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7604
 rt_mutex_slowlock_block+0x55c/0x680 kernel/locking/rtmutex.c:1670
 __rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
 __rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1787 [inline]
 rt_mutex_slowlock+0x2d4/0x780 kernel/locking/rtmutex.c:1827
 __rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
 __mutex_lock_common kernel/locking/rtmutex_api.c:560 [inline]
 mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:578
 bdev_open+0xde/0xd00 block/bdev.c:991
 bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1105
 fs_bdev_file_open_by_dev fs/super.c:1708 [inline]
 setup_bdev_super+0x5a/0x680 fs/super.c:1800
 get_tree_bdev_flags+0x388/0x4f0 fs/super.c:1879
 vfs_get_tree+0x92/0x2a0 fs/super.c:1941
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3777 [inline]
 do_new_mount+0x319/0xdc0 fs/namespace.c:3853
 do_mount fs/namespace.c:4186 [inline]
 __do_sys_mount fs/namespace.c:4402 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4379
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fabc9c5de59
RSP: 002b:00007fabc7eb6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fabc9ee5fa0 RCX: 00007fabc9c5de59
RDX: 0000200000000040 RSI: 0000200000000240 RDI: 0000200000000000
RBP: 00007fabc9cf3e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000002200010 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fabc9ee6038 R14: 00007fabc9ee5fa0 R15: 00007ffef8609f28
 </TASK>
INFO: task syz.0.10484:5598 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.0.10484     state:D stack:28392 pid:5598  tgid:5593  ppid:1440   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x1709/0x5530 kernel/sched/core.c:7231
 __schedule_loop kernel/sched/core.c:7308 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7323
 super_lock+0x1e0/0x3d0 fs/super.c:118
 super_lock_excl fs/super.c:149 [inline]
 grab_super fs/super.c:656 [inline]
 sget_fc+0x35c/0x1a60 fs/super.c:931
 sget_dev fs/super.c:1480 [inline]
 get_tree_bdev_flags+0x212/0x4f0 fs/super.c:1867
 vfs_get_tree+0x92/0x2a0 fs/super.c:1941
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3777 [inline]
 do_new_mount+0x319/0xdc0 fs/namespace.c:3853
 do_mount fs/namespace.c:4186 [inline]
 __do_sys_mount fs/namespace.c:4402 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4379
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fabc9c5de59
RSP: 002b:00007fabc7e74028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fabc9ee6180 RCX: 00007fabc9c5de59
RDX: 0000200000000040 RSI: 0000200000000240 RDI: 0000200000000000
RBP: 00007fabc9cf3e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000002200010 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fabc9ee6218 R14: 00007fabc9ee6180 R15: 00007ffef8609f28
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/39:
 #0: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
2 locks held by getty/5362:
 #0: ffff88803579b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
1 lock held by udevd/28243:
 #0: ffff888026ff44c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd00 block/bdev.c:991
2 locks held by syz.0.10484/5594:
 #0: ffff888021b660e0 (&type->s_umount_key#96/1){+.+.}-{4:4}, at: alloc_super fs/super.c:365 [inline]
 #0: ffff888021b660e0 (&type->s_umount_key#96/1){+.+.}-{4:4}, at: sget_fc+0x97c/0x1a60 fs/super.c:889
 #1: ffff888026ff44c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd00 block/bdev.c:991
1 lock held by syz.6.11305/7841:
 #0: ffff88803779a510 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1158
8 locks held by syz-executor/8038:
 #0: ffff888036780510 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2731 [inline]
 #0: ffff888036780510 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x231/0xbb0 fs/read_write.c:683
 #1: ffff88805e9ab878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1d9/0x540 fs/kernfs/file.c:336
 #2: ffff888029ae50f8 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:73 [inline]
 #2: ffff888029ae50f8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x22c/0x540 fs/kernfs/file.c:337
 #3: ffffffff8f0346d8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd6/0x370 drivers/net/netdevsim/bus.c:234
 #4: ffff88805cdcb160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
 #4: ffff88805cdcb160 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
 #4: ffff88805cdcb160 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb9/0x880 drivers/base/dd.c:1369
 #5: ffff88804eba6310 (&devlink->lock_key#20){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1799
 #6: ffffffff8f7b5d18 (netdev_trace_buffer_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #6: ffffffff8f7b5d18 (netdev_trace_buffer_lock){+.+.}-{3:3}, at: erase_netdev_trace_buffer net/core/dev.c:13412 [inline]
 #6: ffffffff8f7b5d18 (netdev_trace_buffer_lock){+.+.}-{3:3}, at: free_netdev+0x551/0x8f0 net/core/dev.c:12254
 #7: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #7: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #7: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
 #7: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
4 locks held by syz.9.11397/8124:
 #0: ffff88804e1b2cb0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline]
 #0: ffff88804e1b2cb0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1a4/0x9f0 mm/mmap.c:1284
 #1: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #1: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #1: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290
 #2: ffff88803ddf47d8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
 #2: ffff88803ddf47d8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404
 #3: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #3: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #3: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
 #3: ffffffff8e3c3780 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
3 locks held by dhcpcd-run-hook/8142:
 #0: ffffffff8e4967f0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1542 [inline]
 #0: ffffffff8e4967f0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10f/0x480 kernel/fork.c:1595
 #1: ffff88803c3462b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
 #1: ffff88803c3462b0 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x16e/0x1d40 mm/mmap.c:1739
 #2: ffff88801ae97030 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:544 [inline]
 #2: ffff88801ae97030 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x256/0x1d40 mm/mmap.c:1746

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:158 [inline]
 sys_info+0x135/0x170 lib/sys_info.c:166
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xfd7/0x1030 kernel/hung_task.c:561
 kthread+0x388/0x470 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: fb 76 02 c3 cc cc cc cc cc cc cc 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 d3 fc 1c 00 fb f4 <e9> cc cf 03 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc900001e7e40 EFLAGS: 00000246
RAX: 0000000000a050f5 RBX: ffffffff81996540 RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d981bf2 RDI: ffffffff8bcb9980
RBP: ffffc900001e7f10 R08: ffff8880b8733d5b R09: 1ffff110170e67ab
R10: dffffc0000000000 R11: ffffed10170e67ac R12: 0000000000000000
R13: 1ffff11003c51ba0 R14: 1ffff9200003cfd0 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888125b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbfcf387dac CR3: 000000000e1b0000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000071 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/kernel/process.c:767 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:768
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x2e0/0x540 kernel/sched/idle.c:355
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x157
 </TASK>