INFO: task syz-executor360:5073 blocked for more than 143 seconds.
      Not tainted 6.9.0-rc7-syzkaller-00136-gf4345f05c0df #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor360 state:D stack:25464 pid:5073  tgid:5073  ppid:5072   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5409 [inline]
 __schedule+0x1796/0x4a00 kernel/sched/core.c:6746
 __schedule_loop kernel/sched/core.c:6823 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6838
 schedule_timeout+0xb0/0x310 kernel/time/timer.c:2558
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x355/0x620 kernel/sched/completion.c:148
 __flush_workqueue+0x7d6/0x1710 kernel/workqueue.c:4007
 nbd_start_device_ioctl drivers/block/nbd.c:1463 [inline]
 __nbd_ioctl drivers/block/nbd.c:1524 [inline]
 nbd_ioctl+0xbd1/0xf40 drivers/block/nbd.c:1564
 blkdev_ioctl+0x5e5/0x740 block/ioctl.c:642
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:904 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f711f084879
RSP: 002b:00007ffcf3e105c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f711f084879
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007f711f0f75f0 R08: 0000000000000006 R09: 0000000000000006
R10: 0000000000000006 R11: 0000000000000246 R12: 0000000000000001
R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
 #0: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614
2 locks held by kworker/u9:1/4472:
 #0: ffff888020975148 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3242 [inline]
 #0: ffff888020975148 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3348
 #1: ffffc9000d7afd00 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3243 [inline]
 #1: ffffc9000d7afd00 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3348
2 locks held by getty/4827:
 #0: ffff88802acd70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002f0e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201

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

NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.9.0-rc7-syzkaller-00136-gf4345f05c0df #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+0x241/0x360 lib/dump_stack.c:114
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xfde/0x1020 kernel/hung_task.c:380
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4517 Comm: klogd Not tainted 6.9.0-rc7-syzkaller-00136-gf4345f05c0df #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:PageTail include/linux/page-flags.h:285 [inline]
RIP: 0010:const_folio_flags include/linux/page-flags.h:313 [inline]
RIP: 0010:folio_test_slab include/linux/page-flags.h:527 [inline]
RIP: 0010:virt_to_slab mm/kasan/../slab.h:206 [inline]
RIP: 0010:qlink_to_cache+0x2a/0xb0 mm/kasan/quarantine.c:131
Code: e8 fb 23 4b ff 48 c1 e8 06 48 83 e0 c0 48 ba 00 00 00 00 00 ea ff ff 48 8b 4c 10 08 f6 c1 01 75 44 48 01 d0 66 90 48 8b 48 08 <f6> c1 01 75 65 66 90 48 8b 08 48 c1 e1 34 48 c1 f9 3f 48 21 c1 48
RSP: 0018:ffffc90003957680 EFLAGS: 00000286
RAX: ffffea0000939800 RBX: ffff888024e64400 RCX: ffff888015eeb8c0
RDX: ffffea0000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888021326400 R08: ffffffff81429ccc R09: ffffffff81f77223
R10: dffffc0000000000 R11: fffffbfff25dfca6 R12: 0000000000000000
R13: ffff888024e64400 R14: ffffc900039576b8 R15: 0000000000000000
FS:  00007f4b5527e380(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f632efb8580 CR3: 000000007c59e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 qlist_free_all+0x2e/0xc0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3804 [inline]
 slab_alloc_node mm/slub.c:3851 [inline]
 kmem_cache_alloc_node+0x194/0x390 mm/slub.c:3894
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:658
 alloc_skb include/linux/skbuff.h:1313 [inline]
 alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6515
 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2795
 unix_dgram_sendmsg+0x6d3/0x1f80 net/unix/af_unix.c:2019
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:745
 __sys_sendto+0x3a4/0x4f0 net/socket.c:2191
 __do_sys_sendto net/socket.c:2203 [inline]
 __se_sys_sendto net/socket.c:2199 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2199
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4b553e09b5
Code: 8b 44 24 08 48 83 c4 28 48 98 c3 48 98 c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 26 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 7a 48 8b 15 44 c4 0c 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffff2645788 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f4b553e09b5
RDX: 000000000000004c RSI: 000055e37aef0d80 RDI: 0000000000000003
RBP: 000055e37aeec910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013
R13: 00007f4b5556e212 R14: 00007ffff2645888 R15: 0000000000000000
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.320 msecs