INFO: task kworker/u4:1:11 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:1    state:D stack:21360 pid:11    ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
 rq_qos_wait+0x227/0x350 block/blk-rq-qos.c:282
 __wbt_wait block/blk-wbt.c:522 [inline]
 wbt_wait+0x384/0x650 block/blk-wbt.c:586
 __rq_qos_throttle+0x61/0xa0 block/blk-rq-qos.c:66
 rq_qos_throttle block/blk-rq-qos.h:207 [inline]
 blk_mq_get_new_requests block/blk-mq.c:2924 [inline]
 blk_mq_submit_bio+0x8ef/0x2100 block/blk-mq.c:3023
 __submit_bio+0x1a2/0x290 block/blk-core.c:591
 __submit_bio_noacct_mq block/blk-core.c:668 [inline]
 submit_bio_noacct_nocheck+0x7f1/0xaa0 block/blk-core.c:697
 ext4_io_submit+0xd8/0x140 fs/ext4/page-io.c:378
 ext4_writepages+0xf76/0x2e70 fs/ext4/inode.c:2877
 do_writepages+0x3c6/0x640 mm/page-writeback.c:2491
 __writeback_single_inode+0x153/0x1170 fs/fs-writeback.c:1673
 writeback_sb_inodes+0xad5/0x17f0 fs/fs-writeback.c:1964
 __writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2035
 wb_writeback+0x484/0xd40 fs/fs-writeback.c:2140
 wb_check_old_data_flush fs/fs-writeback.c:2240 [inline]
 wb_do_writeback fs/fs-writeback.c:2293 [inline]
 wb_workfn+0xb68/0xee0 fs/fs-writeback.c:2321
 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task syz.0.225:4664 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.225       state:D stack:27632 pid:4664  ppid:4410   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115
 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250
 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945
 __ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119
 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156
 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500
 generic_update_time fs/inode.c:1946 [inline]
 inode_update_time fs/inode.c:1959 [inline]
 __file_update_time+0x21d/0x240 fs/inode.c:2147
 file_update_time+0x2f3/0x370 fs/inode.c:2178
 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274
 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009
 do_shared_fault mm/memory.c:4694 [inline]
 do_fault mm/memory.c:4762 [inline]
 handle_pte_fault mm/memory.c:5029 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292
 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7efe9d46ba23
RSP: 002b:00007ffcecb8b3c0 EFLAGS: 00010246
RAX: 000000000003fde8 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000001b30524000 RSI: 0000000000040000 RDI: 00007efe9d7e0708
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffcecb8b650
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u4:1/11:
 #0: ffff888019a8d138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #1: ffffc90000107d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #2: ffff88807e1920e0 (&type->s_umount_key#32){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:415
 #3: ffff88807e194c18 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2e70 fs/ext4/inode.c:2717
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2e4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cb2ed10 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2db60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6527
3 locks held by kworker/u4:4/57:
2 locks held by getty/4026:
 #0: ffff88814d4d5098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
3 locks held by syz.0.225/4664:
 #0: ffff88801f720158 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88801f720158 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
 #0: ffff88801f720158 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
 #1: ffff88807e192558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1891 [inline]
 #1: ffff88807e192558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1995 [inline]
 #1: ffff88807e192558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6273
 #2: ffff88807e196990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
3 locks held by syz-executor/4665:
 #0: ffff88807e192460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:402
 #1: ffff888074e67258 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #1: ffff888074e67258 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: filename_create+0x20b/0x450 fs/namei.c:3884
 #2: ffff88807e196990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf0e/0xf50 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 46 Comm: kworker/u4:3 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:error_entry+0x0/0xf0 arch/x86/entry/entry_64.S:1036
Code: 00 4c 89 fa 89 d0 48 c1 ea 20 0f 30 66 90 f3 48 0f ae db e9 6f fe ff ff 85 db 0f 85 67 fe ff ff 0f 01 f8 e9 5f fe ff ff 90 90 <56> 48 8b 74 24 08 48 89 7c 24 08 52 51 50 41 50 41 51 41 52 41 53
RSP: 0018:ffffc90000b77578 EFLAGS: 00000046
RAX: ffff888017441dc0 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000400 RDI: ffffffff8cc1f020
RBP: 0000000000000b20 R08: 0000000000000b20 R09: ffffc90000b77ad0
R10: dffffc0000000000 R11: fffff5200016ef5e R12: ffffffff89b572d4
R13: 00000000ffffffff R14: ffff888017441dc0 R15: 0000000000000260
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000061637265010 CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 asm_exc_int3+0x2a/0x40 arch/x86/include/asm/idtentry.h:607
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:kfence_alloc include/linux/kfence.h:120 [inline]
RIP: 0010:slab_alloc_node mm/slub.c:3283 [inline]
RIP: 0010:__kmem_cache_alloc_node+0x60/0x270 mm/slub.c:3398
Code: 00 00 00 31 db 48 8d 54 24 08 b9 01 00 00 00 31 f6 41 89 e8 e8 01 16 00 00 48 85 c0 0f 84 4a 01 00 00 49 89 c6 4c 89 3c 24 cc <1f> 44 00 00 49 8b 06 65 48 03 05 89 91 2f 7e 48 8b 50 08 4c 8b 38
RSP: 0018:ffffc90000b775e8 EFLAGS: 00000286
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa3/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 ieee802_11_parse_elems_full+0xb4/0x1240 net/mac80211/util.c:1503
 ieee802_11_parse_elems_crc net/mac80211/ieee80211_i.h:2265 [inline]
 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2272 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1605 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x3f9/0x2eb0 net/mac80211/ibss.c:1638
 ieee80211_iface_process_skb net/mac80211/iface.c:1679 [inline]
 ieee80211_iface_work+0x72c/0xc70 net/mac80211/iface.c:1733
 cfg80211_wiphy_work+0x224/0x260 net/wireless/core.c:433
 process_one_work+0x8ab/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaf5/0x12a0 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>