INFO: task syz-executor.2:22754 blocked for more than 143 seconds.
      Not tainted 5.15.110-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:23584 pid:22754 ppid: 21652 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1860
 do_wait_for_common+0x2d9/0x480 kernel/sched/completion.c:85
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
 xfs_buf_iowait+0xb4/0x400 fs/xfs/xfs_buf.c:1573
 xfs_buf_delwri_pushbuf+0x2cf/0x4b0 fs/xfs/xfs_buf.c:2251
 xfs_qm_flush_one+0x266/0x350 fs/xfs/xfs_qm.c:1249
 xfs_qm_dquot_walk+0x22a/0x4a0 fs/xfs/xfs_qm.c:86
 xfs_qm_quotacheck+0x2f7/0x640 fs/xfs/xfs_qm.c:1335
 xfs_qm_mount_quotas+0x328/0x610 fs/xfs/xfs_qm.c:1441
 xfs_mountfs+0x162b/0x1ca0 fs/xfs/xfs_mount.c:904
 xfs_fs_fill_super+0x100c/0x1240 fs/xfs/xfs_super.c:1658
 get_tree_bdev+0x3fe/0x620 fs/super.c:1303
 vfs_get_tree+0x88/0x270 fs/super.c:1508
 do_new_mount+0x28b/0xad0 fs/namespace.c:2994
 do_mount fs/namespace.c:3337 [inline]
 __do_sys_mount fs/namespace.c:3545 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3522
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fec768e969a
RSP: 002b:00007fec74e59f88 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000000096cb RCX: 00007fec768e969a
RDX: 0000000020009700 RSI: 0000000020009740 RDI: 00007fec74e59fe0
RBP: 00007fec74e5a020 R08: 00007fec74e5a020 R09: 0000000002000000
R10: 0000000002000000 R11: 0000000000000202 R12: 0000000020009700
R13: 0000000020009740 R14: 00007fec74e59fe0 R15: 0000000020000000
 </TASK>
INFO: task syz-executor.4:22800 blocked for more than 143 seconds.
      Not tainted 5.15.110-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4  state:D stack:22720 pid:22800 ppid:  3540 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6514
 __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
 xfs_qm_dqfree_one+0x66/0x170 fs/xfs/xfs_qm.c:1607
 xfs_qm_shrink_scan+0x314/0x3d0 fs/xfs/xfs_qm.c:523
 do_shrink_slab+0x542/0xda0 mm/vmscan.c:758
 shrink_slab+0x233/0x960 mm/vmscan.c:918
 drop_slab_node+0xed/0x180 mm/vmscan.c:953
 drop_slab+0x8b/0x120 mm/vmscan.c:963
 drop_caches_sysctl_handler+0xb3/0x160 fs/drop_caches.c:66
 proc_sys_call_handler+0x541/0x8a0 fs/proc/proc_sysctl.c:587
 do_iter_readv_writev+0x594/0x7a0
 do_iter_write+0x1ea/0x760 fs/read_write.c:855
 iter_file_splice_write+0x806/0xfa0 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0xe3/0x1c0 fs/splice.c:936
 splice_direct_to_actor+0x500/0xc10 fs/splice.c:891
 do_splice_direct+0x285/0x3d0 fs/splice.c:979
 do_sendfile+0x625/0xff0 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1311 [inline]
 __se_sys_sendfile64+0xfc/0x1e0 fs/read_write.c:1303
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fef6aafc169
RSP: 002b:00007fef6906e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fef6ac1bf80 RCX: 00007fef6aafc169
RDX: 0000000020002080 RSI: 0000000000000004 RDI: 0000000000000005
RBP: 00007fef6ab57ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000875 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe233582cf R14: 00007fef6906e300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91c4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3261:
 #0: ffff88814b27c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002bb32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1da0 drivers/tty/n_tty.c:2147
3 locks held by syz-executor.2/22754:
 #0: ffff8880787580e0 (&type->s_umount_key#81/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229
 #1: ffff888147c0e158 (&qinf->qi_tree_lock){+.+.}-{3:3}, at: xfs_qm_dquot_walk+0x132/0x4a0 fs/xfs/xfs_qm.c:73
 #2: ffff88808dd6e9b8 (&dqp->q_qlock){+.+.}-{3:3}, at: xfs_dqlock fs/xfs/xfs_dquot.h:133 [inline]
 #2: ffff88808dd6e9b8 (&dqp->q_qlock){+.+.}-{3:3}, at: xfs_qm_flush_one+0xca/0x350 fs/xfs/xfs_qm.c:1225
3 locks held by syz-executor.4/22800:
 #0: ffff88807f32c460 (sb_writers#4){.+.+}-{0:0}, at: do_sendfile+0x600/0xff0 fs/read_write.c:1248
 #1: ffffffff8c9b9eb0 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x125/0x960 mm/vmscan.c:908
 #2: ffff888147c0e158 (&qinf->qi_tree_lock){+.+.}-{3:3}, at: xfs_qm_dqfree_one+0x66/0x170 fs/xfs/xfs_qm.c:1607
2 locks held by syz-executor.2/22849:
 #0: ffff888040b820e0 (&type->s_umount_key#23/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229
 #1: ffffffff8c9b9eb0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_memcg_shrinker mm/vmscan.c:359 [inline]
 #1: ffffffff8c9b9eb0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_shrinker+0x92/0x7c0 mm/vmscan.c:620
2 locks held by syz-executor.4/22853:
 #0: ffff8880247ce0e0 (&type->s_umount_key#23/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229
 #1: ffffffff8c9b9eb0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_memcg_shrinker mm/vmscan.c:359 [inline]
 #1: ffffffff8c9b9eb0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_shrinker+0x92/0x7c0 mm/vmscan.c:620
2 locks held by syz-executor.2/22858:
 #0: ffff8880954500e0 (&type->s_umount_key#23/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229
 #1: ffffffff8c9b9eb0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_memcg_shrinker mm/vmscan.c:359 [inline]
 #1: ffffffff8c9b9eb0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_shrinker+0x92/0x7c0 mm/vmscan.c:620
2 locks held by syz-executor.4/22864:
 #0: ffff88808a1fe0e0 (&type->s_umount_key#23/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229
 #1: ffffffff8c9b9eb0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_memcg_shrinker mm/vmscan.c:359 [inline]
 #1: ffffffff8c9b9eb0 (shrinker_rwsem){++++}-{3:3}, at: prealloc_shrinker+0x92/0x7c0 mm/vmscan.c:620

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.110-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb 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:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 2944 Comm: syslogd Not tainted 5.15.110-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
RIP: 0010:__read_once_word_nocheck+0x3/0x10 include/asm-generic/rwonce.h:67
Code: c1 0f 8c dc fc ff ff 48 89 df e8 38 c9 90 00 48 ba 00 00 00 00 00 fc ff df e9 c5 fc ff ff 66 0f 1f 84 00 00 00 00 00 48 8b 07 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 31 c0 81 ff 03 00 00 40 0f
RSP: 0018:ffffc90002c0f328 EFLAGS: 00000287
RAX: ffff88808a601488 RBX: ffffc90002c0f420 RCX: 0000000000000000
RDX: ffffc90002c0f460 RSI: ffffc90002c0f940 RDI: ffffc90002c0f940
RBP: ffffc90002c10000 R08: ffffc90002c0f940 R09: ffffc90002c0f470
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffc90002c08000 R14: ffffc90002c0f460 R15: ffffc90002c0f940
FS:  00007f9a7b565380(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c006f5a000 CR3: 0000000022fdc000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 deref_stack_reg+0xbe/0x110 arch/x86/kernel/unwind_orc.c:360
 unwind_next_frame+0x12f1/0x1fa0
 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+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0xf1/0x270 mm/slub.c:4559
 skb_free_head net/core/skbuff.c:655 [inline]
 skb_release_data+0x73a/0x8a0 net/core/skbuff.c:677
 skb_release_all net/core/skbuff.c:742 [inline]
 __kfree_skb net/core/skbuff.c:756 [inline]
 consume_skb+0xa3/0x140 net/core/skbuff.c:914
 skb_free_datagram+0x24/0xe0 net/core/datagram.c:325
 __unix_dgram_recvmsg+0xcb3/0x1260 net/unix/af_unix.c:2397
 sock_recvmsg_nosec net/socket.c:947 [inline]
 sock_recvmsg net/socket.c:965 [inline]
 sock_read_iter+0x353/0x480 net/socket.c:1038
 call_read_iter include/linux/fs.h:2097 [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+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f9a7b6b9b6a
Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffe852feb08 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f9a7b6b9b6a
RDX: 00000000000000ff RSI: 000055d43aeaa950 RDI: 0000000000000000
RBP: 000055d43aeaa910 R08: 0000000000000001 R09: 0000000000000000
R10: 00007f9a7b8583a3 R11: 0000000000000246 R12: 000055d43aeaa996
R13: 000055d43aeaa950 R14: 0000000000000000 R15: 00007f9a7b896a80
 </TASK>