syzbot


INFO: task hung in rtnl_lock

Status: premoderation: reported syz repro on 2025/06/21 03:33
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+4a860304c330d572cd91@syzkaller.appspotmail.com
First crash: 277d, last: 49m
Bug presence (2)
Date Name Commit Repro Result
2025/06/28 lts (merge base) e0e2f7824338 syz [report] INFO: task hung in rtnl_lock
2025/06/28 upstream (ToT) 35e261cd95dd syz [report] INFO: task hung in rtnl_lock
Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in rtnl_lock 1 41 2240d 2341d 0/1 auto-closed as invalid on 2020/06/04 06:12
upstream INFO: task hung in rtnl_lock (2) net 1 1 1487d 1487d 0/29 auto-closed as invalid on 2022/05/28 17:21
linux-5.15 INFO: task hung in rtnl_lock (2) 1 1 806d 806d 0/3 auto-obsoleted due to no activity on 2024/04/18 21:58
linux-4.14 INFO: task hung in rtnl_lock 1 12 2231d 2341d 0/1 auto-closed as invalid on 2020/06/13 20:56
android-49 INFO: task hung in rtnl_lock 1 7 2304d 2342d 0/3 auto-closed as invalid on 2020/04/01 22:32
linux-6.1 INFO: task hung in rtnl_lock 1 7 962d 1084d 0/3 auto-obsoleted due to no activity on 2023/11/14 10:24
linux-6.1 INFO: task hung in rtnl_lock (2) origin:lts-only 1 C inconclusive 407 1d00h 835d 0/3 upstream: reported C repro on 2023/12/11 07:58
upstream INFO: task hung in rtnl_lock (3) net 1 C 128 734d 1085d 25/29 fixed on 2024/03/26 17:39
linux-5.15 INFO: task hung in rtnl_lock (3) origin:upstream 1 C error 311 26d 674d 0/3 upstream: reported C repro on 2024/05/20 16:41
upstream INFO: task hung in rtnl_lock net 1 118 2142d 2088d 0/29 auto-closed as invalid on 2020/09/10 12:52
linux-5.15 INFO: task hung in rtnl_lock 1 4 959d 1084d 0/3 auto-obsoleted due to no activity on 2023/11/17 15:29
Last patch testing requests (7)
Created Duration User Patch Repo Result
2025/12/03 04:04 6m retest repro android16-6.12 error
2025/12/03 04:04 4m retest repro android16-6.12 error
2025/12/02 23:51 12m retest repro android16-6.12 error
2025/12/02 23:51 4m retest repro android16-6.12 error
2025/12/02 23:51 12m retest repro android16-6.12 error
2025/12/02 23:51 3m retest repro android16-6.12 error
2025/12/02 23:51 12m retest repro android16-6.12 error

Sample crash report:
INFO: task kworker/u8:2:46 blocked for more than 126 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2    state:D stack:0     pid:46    tgid:46    ppid:2      flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6016 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7864
 __schedule_loop kernel/sched/core.c:7945 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7960
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:8017
 __mutex_lock_common kernel/locking/mutex.c:707 [inline]
 __mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
 mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
 rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
 addrconf_dad_work+0xce/0x1530 net/ipv6/addrconf.c:4234
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319
 worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
 kthread+0x2c9/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
INFO: task kworker/u8:3:359 blocked for more than 132 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:3    state:D stack:0     pid:359   tgid:359   ppid:2      flags:0x00004000
Workqueue: events_unbound linkwatch_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6016 [inline]
 __schedule+0x134f/0x1ea0 kernel/sched/core.c:7864
 __schedule_loop kernel/sched/core.c:7945 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7960
 synchronize_rcu_expedited+0x6eb/0x970 kernel/rcu/tree_exp.h:994
 synchronize_net+0x2c/0x40 net/core/dev.c:11387
 dev_deactivate_many+0x6dd/0xbe0 net/sched/sch_generic.c:1380
 dev_deactivate+0x121/0x1c0 net/sched/sch_generic.c:1406

Crashes (4324):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/10 00:13 android16-6.12 0a7d743a2946 176bead5 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/02/16 21:40 android16-6.12 f2758f0da7bc 5d52cba5 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/02/04 05:08 android16-6.12 a456898cc65b 42b01fab .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/02/03 20:56 android16-6.12 6b31c6eca9a2 6df4c87a .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/02/03 00:32 android16-6.12 12691bc9c3f1 d78927dd .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/02/02 12:00 android16-6.12 c13babfee861 018ebef2 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/01/31 03:43 android16-6.12 c13babfee861 c75a2f6e .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2025/10/20 05:21 android16-6.12 55036ffcd617 1c8c8cd8 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2025/10/13 05:34 android16-6.12 fbb5490cc8c3 ff1712fe .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2025/09/23 05:54 android16-6.12 3907c0eb526d 0ac7291c .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2025/09/09 06:36 android16-6.12 7471f5c09c55 d291dd2d .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2025/07/18 17:50 android16-6.12 2e58e85c038f 88248e14 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2025/07/09 14:50 android16-6.12 acad0cd51d10 f4e5e155 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2025/06/26 09:23 android16-6.12 22d634eb24e3 26d77996 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 22:23 android16-6.12 c27baa2eb103 c6143aac .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 20:08 android16-6.12 ff78c78d65d3 8ee77f7d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 16:41 android16-6.12 ff78c78d65d3 8ee77f7d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 12:26 android16-6.12 ff78c78d65d3 8ee77f7d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 10:59 android16-6.12 ff78c78d65d3 8ee77f7d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 07:56 android16-6.12 ff78c78d65d3 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 05:41 android16-6.12 ff78c78d65d3 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 04:09 android16-6.12 ff78c78d65d3 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 03:06 android16-6.12 d671506859f7 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/25 01:49 android16-6.12 d671506859f7 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/24 23:54 android16-6.12 d671506859f7 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/24 21:27 android16-6.12 d671506859f7 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/24 19:38 android16-6.12 d671506859f7 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/24 16:28 android16-6.12 d671506859f7 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/24 14:35 android16-6.12 d671506859f7 74e70d19 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/24 10:25 android16-6.12 0e9b1ff406b1 baf8bf12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/20 02:24 android16-6.12 e34608848261 bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/20 01:08 android16-6.12 e34608848261 bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 23:47 android16-6.12 e34608848261 bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 22:37 android16-6.12 e34608848261 bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 20:22 android16-6.12 e34608848261 bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 19:06 android16-6.12 e34608848261 bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 17:05 android16-6.12 e34608848261 bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 13:59 android16-6.12 e34608848261 bd6dcb30 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 05:46 android16-6.12 e34608848261 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 04:36 android16-6.12 e34608848261 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 04:04 android16-6.12 e34608848261 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/19 02:27 android16-6.12 e34608848261 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/18 22:25 android16-6.12 426ada0dbee7 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/18 20:09 android16-6.12 426ada0dbee7 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/18 16:59 android16-6.12 426ada0dbee7 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/18 15:58 android16-6.12 426ada0dbee7 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/18 12:15 android16-6.12 426ada0dbee7 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/18 10:44 android16-6.12 426ada0dbee7 0199f9a1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/18 06:49 android16-6.12 18ca40f8c454 c8810548 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/17 22:04 android16-6.12 18ca40f8c454 c8810548 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/17 18:45 android16-6.12 18ca40f8c454 c01bca74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/17 16:55 android16-6.12 d9e7ad6b2d4f c01bca74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/17 16:13 android16-6.12 d9e7ad6b2d4f c01bca74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/17 15:11 android16-6.12 d9e7ad6b2d4f c01bca74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/17 13:32 android16-6.12 d9e7ad6b2d4f c01bca74 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/17 04:54 android16-6.12 d9e7ad6b2d4f 0737c18f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/17 01:05 android16-6.12 d9e7ad6b2d4f 0737c18f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/12 22:25 android16-6.12 d6e2584f0a1d 4efadf07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
2026/03/12 16:27 android16-6.12 d6e2584f0a1d 4efadf07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in rtnl_lock
* Struck through repros no longer work on HEAD.