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INFO: rcu detected stall in addrconf_dad_work (5)

Status: upstream: reported C repro on 2020/09/07 15:59
Subsystems: net
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+251463bfa779ca087ad1@syzkaller.appspotmail.com
First crash: 2104d, last: 11d
Cause bisection: introduced by (bisect log) :
commit 5a781ccbd19e4664babcbe4b4ead7aa2b9283d22
Author: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Date: Sat Sep 29 00:59:43 2018 +0000

  tc: Add support for configuring the taprio scheduler

Crash: no output from test machine (log)
Repro: C syz .config
  
Fix bisection the fix commit could be any of (bisect log):
  fc3abb53250a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid
  9e9fb7655ed5 Merge tag 'net-next-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
   
▶ ▼ ✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision Error
7c5285ef-d277-4e01-8d8a-56e8b1d5c12c assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ INFO: rcu detected stall in addrconf_dad_work (5) 2026/05/30 13:09 2026/05/30 13:09 2026/05/30 14:51 6b4a844333e83556da95d61d7f207e7ef5cd4bc6
d6a1a262-579a-4fa1-ab33-dcfecc5e7900 assessment-security 💥 INFO: rcu detected stall in addrconf_dad_work (5) 2026/05/14 10:20 2026/05/14 10:20 2026/05/14 10:22 6ccb967e465e832a7bfd7a116ad00d52a0923a5d failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 128 From /app/workdir/repo/linux * branch HEAD -> FETCH_HEAD Updating files: 28% (26417/92330) Updating files: 29% (26776/92330) Updating files: 30% (27699/92330) Updating files: 31% (28623/92330) Updating files: 32% (29546/92330) Updating files: 33% (30469/92330) Updating files: 34% (31393/92330) Updating files: 35% (32316/92330) Updating files: 36% (33239/92330) Updating files: 37% (34163/92330) Updating files: 37% (34710/92330) Updating files: 38% (35086/92330) Updating files: 39% (36009/92330) Updating files: 39% (36767/92330) Updating files: 39% (36885/92330) error: unable to write file drivers/gpu/drm/amd/include/asic_reg/gc/gc_9_4_2_offset.h error: unable to write file drivers/gpu/drm/amd/include/asic_reg/gc/gc_9_4_2_sh_mask.h error: unable to write file drivers/gpu/drm/amd/include/asic_reg/gc/gc_9_4_3_offset.h error: unable to write file drivers/gpu/drm/amd/include/asic_reg/gc/gc_9_4_3_sh_mask.h fatal: cannot create directory at 'drivers/gpu/drm/amd/include/asic_reg/gca': No space left on device
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
INFO: rcu detected stall in addrconf_dad_work (5) 0 (1) 2020/09/07 15:59
▶ ▼ Similar bugs (13)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in addrconf_dad_work (4) mm cgroups 1 8 2343d 2344d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in addrconf_dad_work (3) mm 1 6 2344d 2344d 0/29 closed as invalid on 2020/01/08 05:23
linux-4.14 INFO: rcu detected stall in addrconf_dad_work 1 C done 18 2460d 2467d 1/1 fixed on 2019/12/06 10:33
upstream INFO: rcu detected stall in addrconf_dad_work (2) mm 1 15 2378d 2380d 0/29 closed as invalid on 2019/12/04 14:14
linux-6.1 INFO: rcu detected stall in addrconf_dad_work origin:upstream 1 C error 3 149d 564d 0/3 upstream: reported C repro on 2024/11/22 07:19
upstream INFO: rcu detected stall in addrconf_dad_work 1 C done 126 2458d 2463d 13/29 fixed on 2019/10/09 10:54
linux-4.19 INFO: rcu detected stall in addrconf_dad_work (2) 1 C done 1 2363d 2363d 1/1 fixed on 2020/01/19 15:05
linux-5.15 INFO: rcu detected stall in addrconf_dad_work origin:lts-only 1 syz done 5 325d 646d 0/3 upstream: reported syz repro on 2024/09/01 00:22
linux-4.19 INFO: rcu detected stall in addrconf_dad_work 1 C done 19 2455d 2466d 1/1 fixed on 2019/12/07 19:18
linux-5.15 BUG: soft lockup in addrconf_dad_work 1 1 1057d 1057d 0/3 auto-obsoleted due to no activity on 2023/10/25 16:01
linux-4.19 BUG: soft lockup in addrconf_dad_work 1 C error 55 1235d 1576d 0/1 upstream: reported C repro on 2022/02/13 10:05
android-5-15 BUG: soft lockup in addrconf_dad_work 1 3 717d 772d 0/2 auto-obsoleted due to no activity on 2024/09/19 17:30
upstream BUG: soft lockup in addrconf_dad_work net 1 C done 1 2462d 2462d 13/29 fixed on 2019/10/09 10:54
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/04/26 01:11 31m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci error
2026/04/06 19:07 17m retest repro linux-next report log
2026/04/04 13:28 19m retest repro linux-next report log
2026/04/04 13:12 19m retest repro linux-next report log
2026/04/04 12:12 21m retest repro linux-next report log
2026/02/14 16:58 1h09m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci error
2026/01/26 15:29 18m retest repro linux-next report log
2026/01/26 15:15 19m retest repro linux-next report log
2026/01/24 10:31 33m retest repro linux-next error
2026/01/24 06:14 28m retest repro linux-next report log
▶ ▼ Fix bisection attempts (12)
Created Duration User Patch Repo Result
2021/09/01 13:04 16m bisect fix upstream OK (2) job log
2021/08/02 04:03 22m bisect fix upstream OK (0) job log log
2021/07/01 06:56 22m bisect fix upstream OK (0) job log log
2021/06/01 06:34 22m bisect fix upstream OK (0) job log log
2021/05/02 06:00 25m bisect fix upstream OK (0) job log log
2021/04/01 23:43 23m bisect fix upstream OK (0) job log log
2021/03/01 07:32 24m bisect fix upstream OK (0) job log log
2021/02/06 16:31 0m bisect fix upstream error job log
2021/01/07 16:04 26m bisect fix upstream OK (0) job log log
2020/12/07 15:34 24m bisect fix upstream OK (0) job log log
2020/11/07 13:38 25m bisect fix upstream OK (0) job log log
2020/10/08 08:53 26m bisect fix upstream OK (0) job log log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P141/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=12541, q=791 ncpus=2)
task:kworker/u8:5    state:R  running task     stack:21888 pid:141   tgid:141   ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5258 [inline]
 __schedule+0x150e/0x5070 kernel/sched/core.c:6866
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7193
 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_release+0x2a6/0x3b0 kernel/locking/lockdep.c:5893
Code: 4d 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 52 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 2a 0f 01 11 <48> 3b 44 24 28 75 75 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d e9
RSP: 0018:ffffc90002ef6f50 EFLAGS: 00000206
RAX: 1c444a3076aa2400 RBX: 0000000000000202 RCX: 1c444a3076aa2400
RDX: 0000000000000003 RSI: ffffffff8db7ed49 RDI: ffffffff8be07960
RBP: ffff88801db0e728 R08: ffffc90002ef7850 R09: 0000000000000000
R10: ffffc90002ef70d8 R11: fffff520005dee1d R12: 0000000000000003
R13: 0000000000000003 R14: ffffffff8e13f2e0 R15: ffff88801db0db80
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:897 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0x1ab1/0x23d0 arch/x86/kernel/unwind_orc.c:695
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2540 [inline]
 slab_free mm/slub.c:6674 [inline]
 kmem_cache_free+0x197/0x620 mm/slub.c:6785
 netlink_broadcast_filtered+0xec7/0x1000 net/netlink/af_netlink.c:1535
 nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
 nlmsg_multicast include/net/netlink.h:1184 [inline]
 nlmsg_notify+0xf0/0x1a0 net/netlink/af_netlink.c:2593
 inet6_ifa_notify net/ipv6/addrconf.c:5621 [inline]
 __ipv6_ifa_notify+0x226/0xaa0 net/ipv6/addrconf.c:6270
 ipv6_ifa_notify net/ipv6/addrconf.c:6322 [inline]
 addrconf_dad_completed+0x180/0xd60 net/ipv6/addrconf.c:4320
 addrconf_dad_work+0xc36/0x14b0 net/ipv6/addrconf.c:-1
 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279
 process_scheduled_works kernel/workqueue.c:3362 [inline]
 worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: rcu_preempt kthread starved for 10553 jiffies! g12541 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27728 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5258 [inline]
 __schedule+0x150e/0x5070 kernel/sched/core.c:6866
 __schedule_loop kernel/sched/core.c:6948 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6963
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6152 Comm: syz-executor886 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:entry_SYSCALL_64+0xf/0x2b arch/x86/entry/entry_64.S:95
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc f3 0f 1e fa 0f 01 f8 65 48 89 25 85 3f 9e 11 <66> 90 0f 20 dc 0f 1f 44 00 00 48 81 e4 ff e7 ff ff 0f 22 dc 65 48
RSP: 0018:00007f2e3e0aeb88 EFLAGS: 00000002
RAX: 0000000000000027 RBX: 00007f2e3e0aecf0 RCX: 00007f2e3e102077
RDX: 00007f2e3e0aebc0 RSI: 00007f2e3e0aecf0 RDI: 0000000000000021
RBP: 0000000000000000 R08: 00007f2e3e0af6c0 R09: 00007f2e3e0af6c0
R10: 0000000000000000 R11: 0000000000000206 R12: 00007f2e3e1893ec
R13: 000000000000000b R14: 00007ffe2c5fdaa0 R15: 00007ffe2c5fdb88
FS:  00007f2e3e0af6c0(0000) GS:ffff888125c25000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000058 CR3: 0000000077946000 CR4: 00000000003526f0
Call Trace:

Crashes (20):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/02 17:52 linux-next cc3aa43b44bd d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in addrconf_dad_work
2023/08/25 18:28 linux-next 626932085009 03d9c195 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in addrconf_dad_work
2024/02/29 02:34 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 381f163531d8 352ab904 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: soft lockup in addrconf_dad_work
2026/01/03 10:52 linux-next cc3aa43b44bd d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in addrconf_dad_work
2024/04/15 12:53 upstream fe46a7dd189e c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in addrconf_dad_work
2023/09/04 01:04 upstream 6e32dfcccfcc 696ea0d2 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in addrconf_dad_work
2022/02/13 10:24 upstream b81b1829e7e3 8b9ca619 .config console log report syz C ci-upstream-kasan-gce INFO: rcu detected stall in addrconf_dad_work
2022/02/13 10:23 net-next-old 5a8fb33e5305 8b9ca619 .config console log report syz C ci-upstream-net-kasan-gce INFO: rcu detected stall in addrconf_dad_work
2020/09/03 15:50 upstream fc3abb53250a abf9ba4f .config console log report syz C ci-upstream-kasan-gce-root
2024/05/30 03:06 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fda5695d692c 34889ee3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: soft lockup in addrconf_dad_work
2023/07/26 07:54 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci e40939bbfc68 6756545c .config console log report syz [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: soft lockup in addrconf_dad_work
2023/07/19 17:17 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci e40939bbfc68 022df2bb .config console log report syz [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: soft lockup in addrconf_dad_work
2026/01/10 04:47 upstream 372800cb95a3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in addrconf_dad_work
2025/04/06 17:10 upstream f4d2ef48250a 1c65791e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in addrconf_dad_work
2024/11/03 00:59 upstream 11066801dd4b f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in addrconf_dad_work
2024/06/21 09:51 upstream 50736169ecc8 dac2aa43 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in addrconf_dad_work
2024/06/01 05:42 upstream d8ec19857b09 3113787f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in addrconf_dad_work
2026/05/29 02:48 linux-next f7af91adc230 4624854e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in addrconf_dad_work
2025/12/29 20:53 linux-next cc3aa43b44bd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in addrconf_dad_work
2025/12/19 08:30 linux-next cc3aa43b44bd d6526ea3 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: rcu detected stall in addrconf_dad_work
* Struck through repros no longer work on HEAD.