INFO: task syz.3.19591:21048 blocked in I/O wait for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.19591 state:D stack:24112 pid:21048 tgid:21047 ppid:16815 task_flags:0x400040 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]
schedule+0x164/0x2b0 kernel/sched/core.c:7323
io_schedule+0x7f/0xd0 kernel/sched/core.c:8151
folio_wait_bit_common+0x83c/0xbc0 mm/filemap.c:1323
folio_lock include/linux/pagemap.h:1157 [inline]
migrate_folio_unmap mm/migrate.c:1249 [inline]
migrate_pages_batch+0x1baa/0x43d0 mm/migrate.c:1907
migrate_pages_sync mm/migrate.c:2051 [inline]
migrate_pages+0x1f90/0x2900 mm/migrate.c:2133
compact_zone+0x3144/0x4a70 mm/compaction.c:2668
compact_node mm/compaction.c:2937 [inline]
compact_nodes mm/compaction.c:2959 [inline]
sysctl_compaction_handler+0x3f3/0x880 mm/compaction.c:3010
proc_sys_call_handler+0x4c7/0x830 fs/proc/proc_sysctl.c:600
iter_file_splice_write+0xa36/0x1240 fs/splice.c:736
do_splice_from fs/splice.c:936 [inline]
direct_splice_actor+0x104/0x160 fs/splice.c:1159
splice_direct_to_actor+0x586/0xcc0 fs/splice.c:1103
do_splice_direct_actor fs/splice.c:1202 [inline]
do_splice_direct+0x19b/0x2a0 fs/splice.c:1228
do_sendfile+0x540/0x7e0 fs/read_write.c:1371
__do_sys_sendfile64 fs/read_write.c:1426 [inline]
__se_sys_sendfile64+0xdf/0x1a0 fs/read_write.c:1418
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: 0033:0x7f246f20de59
RSP: 002b:00007f246d466028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f246f495fa0 RCX: 00007f246f20de59
RDX: 00002000000000c0 RSI: 0000000000000003 RDI: 0000000000000004
RBP: 00007f246f2a3e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f246f496038 R14: 00007f246f495fa0 R15: 00007ffdb9416218
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6821
2 locks held by getty/5387:
#0: ffff8880290b80a0 (&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/10567:
#0: ffff8880277ca4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd00 block/bdev.c:991
1 lock held by udevd/10625:
#0: ffff88802765b4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd00 block/bdev.c:991
6 locks held by kworker/1:9/19253:
#0: ffff88801b366938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffff88801b366938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffff88801b366938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
#1: ffffc90005e1fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffc90005e1fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#1: ffffc90005e1fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7fd/0x1480 kernel/workqueue.c:3344
#2: ffff88802a4aa210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
#2: ffff88802a4aa210 (&dev->mutex){....}-{4:4}, at: hub_event+0x187/0x4cf0 drivers/usb/core/hub.c:5899
#3: ffff88802a4ce658 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3252 [inline]
#3: ffff88802a4ce658 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline]
#3: ffff88802a4ce658 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#3: ffff88802a4ce658 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#3: ffff88802a4ce658 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x20ad/0x4cf0 drivers/usb/core/hub.c:5953
#4: ffff888026553358 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5465 [inline]
#4: ffff888026553358 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
#4: ffff888026553358 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5871 [inline]
#4: ffff888026553358 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x20e1/0x4cf0 drivers/usb/core/hub.c:5953
#5: ffffffff8f0668a0 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x14d/0x17d0 drivers/usb/core/hub.c:3067
1 lock held by syz.3.19591/21048:
#0: ffff888033832510 (sb_writers#3){.+.+}-{0:0}, at: direct_splice_actor+0x49/0x160 fs/splice.c:1158
5 locks held by syz.4.20711/23773:
#0: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: ip6_send_skb+0x10a/0x380 net/ipv6/ip6_output.c:2013
#1: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#1: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: ip6_output+0x11e/0x540 net/ipv6/ip6_output.c:234
#2: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: __local_bh_disable_ip+0x3c/0x420 kernel/softirq.c:163
#3: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#3: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: process_backlog+0x261/0xc50 net/core/dev.c:6676
#4: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#4: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#4: ffffffff8e3c37c0 (rcu_read_lock){....}-{1:3}, at: ip6_input+0x23/0x270 net/ipv6/ip6_input.c:544
1 lock held by syz.2.20719/23780:
#0: ffff888060adc0e8 (&kvm->slots_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#0: ffff888060adc0e8 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_vm_ioctl_set_memory_region+0x67/0xa0 virt/kvm/kvm_main.c:2146
2 locks held by syz.0.20720/23784:
#0: ffff8880569880a0 (&vcpu->mutex){+.+.}-{4:4}, at: kvm_vcpu_ioctl+0x282/0xfe0 virt/kvm/kvm_main.c:4438
#1: ffff888011fd1b48 (&kvm->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline]
#1: ffff888011fd1b48 (&kvm->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline]
#1: ffff888011fd1b48 (&kvm->srcu){.+.+}-{0:0}, at: kvm_vcpu_srcu_read_lock include/linux/kvm_host.h:963 [inline]
#1: ffff888011fd1b48 (&kvm->srcu){.+.+}-{0:0}, at: kvm_arch_vcpu_ioctl_run+0x1f8/0x1960 arch/x86/kvm/x86.c:8839
=============================================
NMI backtrace for cpu 1
CPU: 1 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:
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:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
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
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 23784 Comm: syz.0.20720 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:__list_del_entry_valid_or_report+0x2a/0x190 lib/list_debug.c:49
Code: f3 0f 1e fa 41 57 41 56 41 55 41 54 53 48 89 fb 49 bd 00 00 00 00 00 fc ff df 48 83 c7 08 48 89 f8 48 c1 e8 03 42 80 3c 28 00 <74> 05 e8 ff 55 5a fd 4c 8b 7b 08 48 89 d8 48 c1 e8 03 42 80 3c 28
RSP: 0018:ffffc90006db7160 EFLAGS: 00000246
RAX: 1ffffd40001d1d92 RBX: ffffea0000e8ec88 RCX: 0000000000000000
RDX: 1ffffffff1fa112a RSI: dffffc0000000000 RDI: ffffea0000e8ec90
RBP: ffff88801dac9f00 R08: 0000000000000000 R09: 0000000000000080
R10: 0000000000000000 R11: ffffffff8e3c3701 R12: ffff8880b8642de0
R13: dffffc0000000000 R14: ffff88801daca3c0 R15: ffffea0000e8ec88
FS: 00007f8f235e66c0(0000) GS:ffff888125a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000037dbe000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 8000000000000001
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
__list_del_entry_valid include/linux/list.h:132 [inline]
__list_del_entry include/linux/list.h:246 [inline]
list_del include/linux/list.h:260 [inline]
__rmqueue_pcplist+0x130e/0x1b20 mm/page_alloc.c:3354
rmqueue_pcplist mm/page_alloc.c:3382 [inline]
rmqueue mm/page_alloc.c:3412 [inline]
get_page_from_freelist+0x93b/0x26c0 mm/page_alloc.c:3943
__alloc_frozen_pages_noprof+0x1a6/0x390 mm/page_alloc.c:5313
alloc_pages_mpol+0xce/0x280 mm/mempolicy.c:2481
alloc_frozen_pages_noprof mm/mempolicy.c:2552 [inline]
alloc_pages_noprof+0xd2/0x2f0 mm/mempolicy.c:2572
get_free_pages_noprof+0xf/0x80 mm/page_alloc.c:5372
mmu_memory_cache_alloc_obj virt/kvm/kvm_main.c:358 [inline]
__kvm_mmu_topup_memory_cache+0x252/0x600 virt/kvm/kvm_main.c:395
mmu_topup_memory_caches+0xd6/0x170 arch/x86/kvm/mmu/mmu.c:621
kvm_mmu_load+0x9d/0x22b0 arch/x86/kvm/mmu/mmu.c:6192
kvm_mmu_reload arch/x86/kvm/mmu.h:212 [inline]
vcpu_enter_guest arch/x86/kvm/x86.c:8199 [inline]
vcpu_run+0x4c13/0x73e0 arch/x86/kvm/x86.c:8596
kvm_arch_vcpu_ioctl_run+0xe51/0x1960 arch/x86/kvm/x86.c:8929
kvm_vcpu_ioctl+0xa64/0xfe0 virt/kvm/kvm_main.c:4470
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xff/0x170 fs/ioctl.c:583
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: 0033:0x7f8f2538de59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8f235e6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8f25615fa0 RCX: 00007f8f2538de59
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00007f8f25423e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8f25616038 R14: 00007f8f25615fa0 R15: 00007ffcdc5a2478