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: 81d, last: 2d03h
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 498d 564d 0/29 auto-obsoleted due to no activity on 2025/03/13 05:51
android-414 INFO: task hung in exit_aio 1 3 2548d 2549d 0/1 auto-closed as invalid on 2019/10/25 08:40
upstream INFO: task hung in exit_aio (2) fs 1 3 1626d 1704d 0/29 closed as invalid on 2022/02/07 19:09
upstream INFO: task hung in exit_aio (3) fs 1 1 659d 659d 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 164d 306d 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 2443d 3058d 0/29 closed as dup on 2018/04/08 22:50

Sample crash report:
INFO: task syz.0.783:2736 blocked for more than 128 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.783       state:D stack:0     pid:2736  tgid:2734  ppid:289    flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6026 [inline]
 __schedule+0x1399/0x1fa0 kernel/sched/core.c:7880
 __schedule_loop kernel/sched/core.c:7961 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7976
 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
 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: 0033:0x7f88c799c819
RSP: 002b:00007f88c87bb0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f88c7c16098 RCX: 00007f88c799c819
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f88c7c1609c
RBP: 00007f88c7c16090 R08: 7fffffffffffffff R09: 0000000000000000
R10: 000000000000002c R11: 0000000000000246 R12: 0000000000000000
R13: 00007f88c7c16128 R14: 00007ffcb11194f0 R15: 00007ffcb11195d8
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 be874e2189b918d3a78482b02a47602d9287c55c
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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+0x2c6/0x370 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: 20 Comm: rcuop/0 Not tainted syzkaller #0 be874e2189b918d3a78482b02a47602d9287c55c
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:check_region_inline mm/kasan/generic.c:171 [inline]
RIP: 0010:kasan_check_range+0x1b/0x2b0 mm/kasan/generic.c:189
Code: 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 b0 01 48 85 f6 0f 84 c0 01 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 <53> 4c 8d 04 37 49 39 f8 0f 82 29 02 00 00 49 89 f9 49 c1 e9 2f 41
RSP: 0018:ffffc900000074a0 EFLAGS: 00000002
RAX: f3f3f3f8f1f1f101 RBX: ffffffff87cb3540 RCX: ffffffff85a39c68
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff87cb3540
RBP: ffffc900000074c0 R08: ffff8881300239ef R09: 1ffff1102600473d
R10: dffffc0000000000 R11: ffffed102600473e R12: 1ffff92000000e9c
R13: dffffc0000000000 R14: ffffffff87cb3548 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd5eb35aff8 CR3: 000000010c728000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __kasan_check_read+0x15/0x20 mm/kasan/shadow.c:31
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
 queued_spin_trylock include/asm-generic/qspinlock.h:92 [inline]
 do_raw_spin_trylock include/linux/spinlock.h:193 [inline]
 __raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline]
 _raw_spin_trylock+0x78/0x140 kernel/locking/spinlock.c:138
 ___ratelimit+0xf2/0x5b0 lib/ratelimit.c:47
 net_ratelimit+0x20/0x30 net/core/utils.c:40
 br_fdb_update+0x3fb/0x680 net/bridge/br_fdb.c:907
 br_handle_frame_finish+0x3a3/0x1760 net/bridge/br_input.c:141
 nf_hook_bridge_pre net/bridge/br_input.c:301 [inline]
 br_handle_frame+0x5a6/0xba0 net/bridge/br_input.c:424
 __netif_receive_skb_core+0xfae/0x3ab0 net/core/dev.c:5670
 __netif_receive_skb_one_core net/core/dev.c:5774 [inline]
 __netif_receive_skb net/core/dev.c:5889 [inline]
 process_backlog+0x3e5/0xad0 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+0x2c6/0x370 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: 106740 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:ca:d8:f5:e9:d8:d9, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)

Crashes (15):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/23 21:58 android16-6.12 2951620221cf 4c3406dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/04/23 19:48 android16-6.12 2951620221cf 4c3406dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/04/20 06:47 android16-6.12 6532ca3bb1f7 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/04/14 00:44 android16-6.12 6642375b48be 1a086e7c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/04/11 06:52 android16-6.12 030f9ae61381 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
2026/03/29 12:48 android16-6.12 2dda9e2ebc9a b5ceaad2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in exit_aio
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.