INFO: task kworker/u4:2:154 blocked for more than 143 seconds.
      Not tainted 5.15.159-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:2    state:D stack:19520 pid:  154 ppid:     2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:3)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
 __mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 exfat_write_inode+0x65/0x110 fs/exfat/inode.c:87
 write_inode fs/fs-writeback.c:1495 [inline]
 __writeback_single_inode+0x644/0xe30 fs/fs-writeback.c:1705
 writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1930
 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:2001
 wb_writeback+0x465/0xc50 fs/fs-writeback.c:2106
 wb_check_background_flush fs/fs-writeback.c:2172 [inline]
 wb_do_writeback fs/fs-writeback.c:2260 [inline]
 wb_workfn+0xd07/0x1130 fs/fs-writeback.c:2288
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:2/154:
 #0: ffff8881425ec138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc900010cfd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff8880797ac0e0 (&type->s_umount_key#83){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418
 #3: ffff888014fcc0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_write_inode+0x65/0x110 fs/exfat/inode.c:87
2 locks held by getty/3260:
 #0: ffff888024e75098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002bab2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
3 locks held by syz-executor.3/3528:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.159-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3501 Comm: syz-fuzzer Not tainted 5.15.159-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:hlock_class kernel/locking/lockdep.c:197 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3700 [inline]
RIP: 0010:validate_chain+0x11a/0x5930 kernel/locking/lockdep.c:3756
Code: 04 00 00 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 c0 80 bf 8f be 08 00 00 00 e8 5e c7 66 00 48 0f a3 1d b6 1b 5c 0e <72> 25 48 c7 c0 c0 ff 3e 91 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85
RSP: 0018:ffffc90000007960 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000040 RCX: ffffffff81636502
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fbf80c8
RBP: ffffc90000007c10 R08: dffffc0000000000 R09: fffffbfff1f7f01a
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88801b71c6b8 R14: 2c1f16d45a674522 R15: ffff88801b71c6b8
FS:  000000c00005ac90(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560c87829600 CR3: 000000001d6c2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 handle_irq_event+0x196/0x2b0 kernel/irq/handle.c:215
 handle_edge_irq+0x245/0xbf0 kernel/irq/chip.c:822
 generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
 handle_irq arch/x86/kernel/irq.c:231 [inline]
 __common_interrupt+0xd7/0x1f0 arch/x86/kernel/irq.c:250
 common_interrupt+0x9f/0xc0 arch/x86/kernel/irq.c:240
 </IRQ>
 <TASK>
 asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:629
RIP: 0010:unwind_next_frame+0x41b/0x1fa0 arch/x86/kernel/unwind_orc.c:461
Code: 0f b6 04 10 84 c0 0f 85 c5 14 00 00 c6 03 01 49 c7 c6 e0 94 88 8a 49 8d 6e 04 49 8d 5e 05 49 89 ec 49 c1 ec 03 41 0f b6 04 14 <84> c0 0f 85 33 14 00 00 48 89 d8 48 c1 e8 03 0f b6 04 10 84 c0 0f
RSP: 0018:ffffc90002f27148 EFLAGS: 00000a07
RAX: 0000000000000000 RBX: ffffffff8e64658f RCX: ffffffff8df98188
RDX: dffffc0000000000 RSI: ffffffff8e646554 RDI: ffffffff8df9815c
RBP: ffffffff8e64658e R08: 000000000000000d R09: ffffc90002f272f0
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff1cc8cb1
R13: ffffffff81ca07cd R14: ffffffff8e64658a R15: ffffc90002f27200
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 kmem_cache_alloc_node+0x121/0x2c0 mm/slub.c:3256
 __alloc_skb+0xdd/0x590 net/core/skbuff.c:415
 alloc_skb include/linux/skbuff.h:1167 [inline]
 __tcp_send_ack+0x9c/0x630 net/ipv4/tcp_output.c:3983
 tcp_ack_snd_check net/ipv4/tcp_input.c:5565 [inline]
 tcp_rcv_established+0xf01/0x1e20 net/ipv4/tcp_input.c:5990
 tcp_v4_do_rcv+0x423/0x960 net/ipv4/tcp_ipv4.c:1733
 sk_backlog_rcv include/net/sock.h:1059 [inline]
 __release_sock+0x198/0x4b0 net/core/sock.c:2724
 release_sock+0x5d/0x1c0 net/core/sock.c:3265
 tcp_recvmsg+0x25d/0x7f0 net/ipv4/tcp.c:2564
 inet_recvmsg+0x157/0x280 net/ipv4/af_inet.c:859
 sock_recvmsg_nosec net/socket.c:966 [inline]
 sock_recvmsg net/socket.c:984 [inline]
 sock_read_iter+0x353/0x480 net/socket.c:1057
 call_read_iter include/linux/fs.h:2166 [inline]
 new_sync_read fs/read_write.c:404 [inline]
 vfs_read+0xa9f/0xe10 fs/read_write.c:485
 ksys_read+0x1a2/0x2c0 fs/read_write.c:623
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x40720e
Code: 48 83 ec 38 e8 13 00 00 00 48 83 c4 38 5d c3 cc cc cc cc cc cc cc cc cc cc cc cc cc 49 89 f2 48 89 fa 48 89 ce 48 89 df 0f 05 <48> 3d 01 f0 ff ff 76 15 48 f7 d8 48 89 c1 48 c7 c0 ff ff ff ff 48
RSP: 002b:000000c00074b8d8 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000040720e
RDX: 0000000000001000 RSI: 000000c0006da000 RDI: 0000000000000003
RBP: 000000c00074b918 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000000c00008be10
R13: 0000000000000003 R14: 000000c0004e84e0 R15: 0000000000000003
 </TASK>