syzbot


INFO: task hung in exit_aio (2)

Status: premoderation: reported on 2026/02/04 00:47
Reported-by: syzbot+7aa30bcce7ee9473996d@syzkaller.appspotmail.com
First crash: 53d, last: 1d06h
Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in exit_aio (4) fs 1 6 471d 536d 0/29 auto-obsoleted due to no activity on 2025/03/13 05:51
android-414 INFO: task hung in exit_aio 1 3 2521d 2521d 0/1 auto-closed as invalid on 2019/10/25 08:40
upstream INFO: task hung in exit_aio (2) fs 1 3 1598d 1676d 0/29 closed as invalid on 2022/02/07 19:09
upstream INFO: task hung in exit_aio (3) fs 1 1 631d 631d 0/29 auto-obsoleted due to no activity on 2024/10/04 00:29
android-6-12 INFO: task hung in exit_aio 1 38 136d 278d 0/1 auto-obsoleted due to no activity on 2026/01/04 12:01
upstream INFO: task hung in exit_aio fs 1 C 17519 2415d 3030d 0/29 closed as dup on 2018/04/08 22:50

Sample crash report:
INFO: task syz.1.3240:10014 blocked for more than 124 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.3240      state:D stack:0     pid:10014 tgid:10014 ppid:7848   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6016 [inline]
 __schedule+0x1399/0x1fa0 kernel/sched/core.c:7870
 __schedule_loop kernel/sched/core.c:7951 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7966
 schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common+0x369/0x650 kernel/sched/completion.c:127
 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
 exit_aio+0x2ec/0x3c0 fs/aio.c:927
 __mmput+0x30/0x340 kernel/fork.c:1356
 mmput+0x55/0x170 kernel/fork.c:1383
 exit_mm kernel/exit.c:574 [inline]
 do_exit+0x909/0x2720 kernel/exit.c:941
 do_group_exit+0x229/0x2f0 kernel/exit.c:1096
 __do_sys_exit_group kernel/exit.c:1107 [inline]
 __se_sys_exit_group kernel/exit.c:1105 [inline]
 __x64_sys_exit_group+0x43/0x50 kernel/exit.c:1105
 x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f003199c799
RSP: 002b:00007fff954cc118 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f003199c799
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fff954cc17c R08: 0000000000000000 R09: 0000000000000054
R10: 00007f0031c16038 R11: 0000000000000246 R12: 00000000000000b3
R13: 0000000000000054 R14: 000000000007437b R15: 00007fff954cc1d0
 </TASK>
INFO: task syz.6.3242:10021 blocked for more than 125 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.3242      state:D stack:0     pid:10021 tgid:10018 ppid:6675   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6016 [inline]
 __schedule+0x1399/0x1fa0 kernel/sched/core.c:7870
 __schedule_loop kernel/sched/core.c:7951 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7966
 schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common+0x369/0x650 kernel/sched/completion.c:127
 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
 rcu_barrier+0x415/0x540 kernel/rcu/tree.c:4657
 kvm_mmu_uninit_tdp_mmu+0x1df/0x210 arch/x86/kvm/mmu/tdp_mmu.c:51
 kvm_mmu_uninit_vm+0x27/0x60 arch/x86/kvm/mmu/mmu.c:6572
 kvm_arch_destroy_vm+0x398/0x420 arch/x86/kvm/x86.c:12970
 kvm_destroy_vm virt/kvm/kvm_main.c:1355 [inline]
 kvm_put_kvm+0xb04/0x12c0 virt/kvm/kvm_main.c:1392
 kvm_vm_release+0x47/0x70 virt/kvm/kvm_main.c:1415
 __fput+0x1fb/0xa00 fs/file_table.c:429
 ____fput+0x20/0x30 fs/file_table.c:457
 task_work_run+0x1e5/0x260 kernel/task_work.c:246
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0x9ad/0x2720 kernel/exit.c:954
 do_group_exit+0x229/0x2f0 kernel/exit.c:1096
 get_signal+0x1398/0x14e0 kernel/signal.c:2933
 arch_do_signal_or_restart+0xbc/0x760 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x57/0xb0 kernel/entry/common.c:218
 do_syscall_64+0x63/0xf0 arch/x86/entry/common.c:84
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f9233d9c799
RSP: 002b:00007f9234c300e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f9234016188 RCX: 00007f9233d9c799
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f9234016188
RBP: 00007f9234016180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9234016218 R14: 00007fffeeabe6e0 R15: 00007fffeeabe7c8
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 4bc4d07fd992eb4da2ed6b7c018f2a9dd207192e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
 watchdog+0xdad/0xf00 kernel/hung_task.c:423
 kthread+0x2c9/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 33 Comm: rcuop/1 Not tainted syzkaller #0 4bc4d07fd992eb4da2ed6b7c018f2a9dd207192e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:55 [inline]
RIP: 0010:update_stack_state+0x17f/0x4b0 arch/x86/kernel/unwind_frame.c:228
Code: 48 8b 73 28 4c 89 ff 48 89 da 48 8b 8d 60 ff ff ff e8 65 9e f5 ff 85 c0 0f 85 2f 01 00 00 48 8b 85 40 ff ff ff 42 80 3c 28 00 <74> 08 4c 89 f7 e8 87 0b 9b 00 4d 8b 3e 48 8b 85 48 ff ff ff 42 80
RSP: 0018:ffffc90000006f58 EFLAGS: 00000246
RAX: 1ffff92000000e16 RBX: ffffc900000070a8 RCX: 1ffff92000000e17
RDX: 1ffff92000000e18 RSI: 1ffff92000000e16 RDI: ffffc90000007100
RBP: ffffc90000007018 R08: ffffc90000007170 R09: ffffc90000007168
R10: 0000000000000016 R11: ffffffff8175d800 R12: 0000000000000000
R13: dffffc0000000000 R14: ffffc900000070b0 R15: ffffc90000227f48
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556e42d888 CR3: 000000010c39c000 CR4: 00000000003526b0
Call Trace:
 <IRQ>
 unwind_next_frame+0x3c1/0x750 arch/x86/kernel/unwind_frame.c:315
 arch_stack_walk+0x138/0x170 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:49 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:70
 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:565
 poison_kmalloc_redzone mm/kasan/common.c:379 [inline]
 __kasan_kmalloc+0x96/0xb0 mm/kasan/common.c:396
 kasan_kmalloc include/linux/kasan.h:261 [inline]
 __kmalloc_cache_noprof+0x23c/0x470 mm/slub.c:4426
 kmalloc_noprof include/linux/slab.h:881 [inline]
 kzalloc_noprof include/linux/slab.h:1017 [inline]
 ref_tracker_alloc+0x184/0x590 lib/ref_tracker.c:203
 __netdev_tracker_alloc include/linux/netdevice.h:4109 [inline]
 netdev_hold include/linux/netdevice.h:4138 [inline]
 dst_init+0xcf/0x420 net/core/dst.c:52
 dst_alloc+0x163/0x250 net/core/dst.c:93
 rt_dst_alloc net/ipv4/route.c:1647 [inline]
 ip_route_input_slow net/ipv4/route.c:2385 [inline]
 ip_route_input_rcu+0x1a0e/0x2700 net/ipv4/route.c:2499
 ip_route_input_noref+0xd4/0x150 net/ipv4/route.c:2510
 arp_process+0x908/0x1790 net/ipv4/arp.c:841
 NF_HOOK+0x181/0x1e0 include/linux/netfilter.h:317
 arp_rcv+0x2f8/0x490 net/ipv4/arp.c:992
 __netif_receive_skb_one_core net/core/dev.c:5776 [inline]
 __netif_receive_skb net/core/dev.c:5889 [inline]
 process_backlog+0x556/0xad0 net/core/dev.c:6225
 __napi_poll+0xd0/0x610 net/core/dev.c:6876
 napi_poll net/core/dev.c:6945 [inline]
 net_rx_action+0x5ea/0xd80 net/core/dev.c:7067
 handle_softirqs+0x1ad/0x630 kernel/softirq.c:621
 __do_softirq+0xf/0x16 kernel/softirq.c:659
 do_softirq+0xb8/0x110 kernel/softirq.c:503
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_do_batch+0x5d9/0xd40 kernel/rcu/tree.c:2594
 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline]
 rcu_nocb_cb_kthread+0x524/0xb30 kernel/rcu/tree_nocb.h:957
 kthread+0x2c9/0x370 kernel/kthread.c:389
 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
net_ratelimit: 165174 callbacks suppressed
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:1c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 178695 callbacks suppressed
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_1 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth1_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/27 22:59 android16-6.12 0151654f7a9d 74a13a23 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/03/10 06:01 android16-6.12 0a7d743a2946 6972f302 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/03/07 10:23 android16-6.12 792a289062b8 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/03/04 16:20 android16-6.12 2e2251661b98 e6b6b96b .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/03/02 22:20 android16-6.12 a57a57875c30 b9dd6534 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/03/01 06:42 android16-6.12 7de305bfa436 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/02/22 06:26 android16-6.12 7712ca595283 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/02/08 01:49 android16-6.12 6aeca23b5dee 4c131dc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/02/04 00:46 android16-6.12 a456898cc65b 42b01fab .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
* Struck through repros no longer work on HEAD.