WARNING in call_rcu (3)

Status: closed as invalid on 2026/06/11 10:27
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+d17177af4afd8c6f804c@syzkaller.appspotmail.com
First crash: 971d, last: 867d
▶ ▼ ✨ AI Patch Versions (1)
Version Stage Reported Report Link Job
1 moderation 2026/05/18 21:04 Discussion 081c2505-21d7-4259-a6ab-cad80355a99b
▶ ▼ ✨ AI Jobs (4)
ID Workflow Result Correct Bug Created Started Finished Revision
29ae2d48 assessment-security 💥 WARNING in call_rcu (3) 2026/06/09 17:43 2026/06/09 17:43 2026/06/09 18:11 c36c07f6
5e968790 assessment-security 💥 WARNING in call_rcu (3) 2026/06/02 14:45 2026/06/02 14:45 2026/06/02 15:12 62fe1528
f1d56b9f assessment-security 💥 WARNING in call_rcu (3) 2026/05/25 09:29 2026/05/25 09:29 2026/05/25 09:56 c69befb3
081c2505 patching ❓ WARNING in call_rcu (3) 2026/05/18 16:40 2026/05/18 17:16 2026/05/18 21:04 9f74d399
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [net?] WARNING in call_rcu (3) 0 (3) 2026/06/11 10:27
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in call_rcu (2) xfs -1 syz, C 15 1316d 1323d 0/29 auto-obsoleted due to no activity on 2023/04/15 15:13
linux-5.15 WARNING in call_rcu -1 3 1102d 1131d 0/3 auto-obsoleted due to no activity on 2023/11/16 11:10
linux-5.15 WARNING in call_rcu (2) -1 1 949d 947d 0/3 auto-obsoleted due to no activity on 2024/04/17 03:03
upstream WARNING in call_rcu net -1 syz, C done 8 2340d 2347d 15/29 fixed on 2020/05/10 10:41
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/06/06 22:06 29m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci error
2026/03/28 15:44 3h05m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci error
2026/01/17 13:13 1h41m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci report log
2025/11/08 04:52 40m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci report log
2025/08/30 04:19 31m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci report log
2025/06/22 21:27 1h36m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci no crash log
2025/06/20 23:31 19m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci report log
2025/04/13 20:49 19m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci report log
2025/04/11 22:00 19m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci report log
2025/02/02 17:46 29m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci report log

Sample crash report:
------------[ cut here ]------------
ODEBUG: activate active (active state 1) object: 000000007c840c9e object type: rcu_head hint: 0x0
WARNING: CPU: 0 PID: 0 at lib/debugobjects.c:517 debug_print_object lib/debugobjects.c:514 [inline]
WARNING: CPU: 0 PID: 0 at lib/debugobjects.c:517 debug_object_activate+0x360/0x4ac lib/debugobjects.c:732
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.8.0-rc7-syzkaller-g707081b61156 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : debug_print_object lib/debugobjects.c:514 [inline]
pc : debug_object_activate+0x360/0x4ac lib/debugobjects.c:732
lr : debug_print_object lib/debugobjects.c:514 [inline]
lr : debug_object_activate+0x360/0x4ac lib/debugobjects.c:732
sp : ffff800080007ad0
x29: ffff800080007ad0 x28: ffff800093738000 x27: dfff800000000000
x26: ffff80008aef0200 x25: 0000000000000001 x24: ffff0000d010cd00
x23: 0000000000000003 x22: ffff80008b41a2e0 x21: 0000000000000000
x20: ffff80008aef0200 x19: ffff0000d010cd00 x18: ffff800080006fa0
x17: 3963303438633730 x16: ffff80008ad6b09c x15: 0000000000000001
x14: 1fffe00036800002 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000010004 x10: 0000000000ff0100 x9 : 42aaeb85fb1b0600
x8 : 42aaeb85fb1b0600 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000800073b8 x4 : ffff80008ed822c0 x3 : ffff8000805ba130
x2 : 0000000000000001 x1 : 0000000100010002 x0 : 0000000000000000
Call trace:
 debug_print_object lib/debugobjects.c:514 [inline]
 debug_object_activate+0x360/0x4ac lib/debugobjects.c:732
 debug_rcu_head_queue kernel/rcu/rcu.h:227 [inline]
 __call_rcu_common kernel/rcu/tree.c:2700 [inline]
 call_rcu+0x48/0xaf4 kernel/rcu/tree.c:2829
 switch_schedules net/sched/sch_taprio.c:210 [inline]
 advance_sched+0x7e0/0xac0 net/sched/sch_taprio.c:984
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x484/0xca0 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x2c0/0xb64 kernel/time/hrtimer.c:1815
 timer_handler drivers/clocksource/arm_arch_timer.c:674 [inline]
 arch_timer_handler_virt+0x74/0x88 drivers/clocksource/arm_arch_timer.c:685
 handle_percpu_devid_irq+0x2a4/0x804 kernel/irq/chip.c:942
 generic_handle_irq_desc include/linux/irqdesc.h:161 [inline]
 handle_irq_desc kernel/irq/irqdesc.c:672 [inline]
 generic_handle_domain_irq+0x7c/0xc4 kernel/irq/irqdesc.c:728
 __gic_handle_irq drivers/irqchip/irq-gic-v3.c:782 [inline]
 __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:833 [inline]
 gic_handle_irq+0x6c/0x190 drivers/irqchip/irq-gic-v3.c:877
 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:889
 do_interrupt_handler+0xd4/0x138 arch/arm64/kernel/entry-common.c:310
 __el1_irq arch/arm64/kernel/entry-common.c:536 [inline]
 el1_interrupt+0x34/0x68 arch/arm64/kernel/entry-common.c:551
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:556
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:594
 __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:27 [inline]
 arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:49
 cpuidle_idle_call kernel/sched/idle.c:170 [inline]
 do_idle+0x1f0/0x4e8 kernel/sched/idle.c:312
 cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:410
 rest_init+0x2dc/0x2f4 init/main.c:730
 start_kernel+0x0/0x4ec init/main.c:827
 start_kernel+0x3ec/0x4ec init/main.c:1072
 __primary_switched+0x84/0x8c arch/arm64/kernel/head.S:243
irq event stamp: 700776
hardirqs last  enabled at (700775): [<ffff80008ad6bc6c>] default_idle_call+0xf4/0x128 kernel/sched/idle.c:103
hardirqs last disabled at (700776): [<ffff80008ad66a78>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (700776): [<ffff80008ad66a78>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last  enabled at (700464): [<ffff80008002189c>] softirq_handle_end kernel/softirq.c:399 [inline]
softirqs last  enabled at (700464): [<ffff80008002189c>] __do_softirq+0xac8/0xce4 kernel/softirq.c:582
softirqs last disabled at (700459): [<ffff80008002ab48>] ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:81
---[ end trace 0000000000000000 ]---
------------[ cut here ]------------
ODEBUG: active_state active (active state 1) object: 000000007c840c9e object type: rcu_head hint: 0x0
WARNING: CPU: 0 PID: 0 at lib/debugobjects.c:517 debug_print_object lib/debugobjects.c:514 [inline]
WARNING: CPU: 0 PID: 0 at lib/debugobjects.c:517 debug_object_active_state+0x2a8/0x37c lib/debugobjects.c:954
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W          6.8.0-rc7-syzkaller-g707081b61156 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : debug_print_object lib/debugobjects.c:514 [inline]
pc : debug_object_active_state+0x2a8/0x37c lib/debugobjects.c:954
lr : debug_print_object lib/debugobjects.c:514 [inline]
lr : debug_object_active_state+0x2a8/0x37c lib/debugobjects.c:954
sp : ffff800080007ad0
x29: ffff800080007ad0 x28: 00000000000000c0 x27: dfff800000000000
x26: 1fffe0001a95d34b x25: 0000000000000003 x24: ffff800093738000
x23: 0000000000000001 x22: ffff80008aef0200 x21: ffff0000d010cd00
x20: ffff80008b41a2e0 x19: 0000000000000000 x18: ffff800080006fa0
x17: 3863373030303030 x16: ffff80008ad6b09c x15: 0000000000000001
x14: 1fffe00036800002 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000010004 x10: 0000000000ff0100 x9 : 42aaeb85fb1b0600
x8 : 42aaeb85fb1b0600 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000800073b8 x4 : ffff80008ed822c0 x3 : ffff8000805ba130
x2 : 0000000000000001 x1 : 0000000100010002 x0 : 0000000000000000
Call trace:
 debug_print_object lib/debugobjects.c:514 [inline]
 debug_object_active_state+0x2a8/0x37c lib/debugobjects.c:954
 debug_rcu_head_queue kernel/rcu/rcu.h:228 [inline]
 __call_rcu_common kernel/rcu/tree.c:2700 [inline]
 call_rcu+0x60/0xaf4 kernel/rcu/tree.c:2829
 switch_schedules net/sched/sch_taprio.c:210 [inline]
 advance_sched+0x7e0/0xac0 net/sched/sch_taprio.c:984
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x484/0xca0 kernel/time/hrtimer.c:1753
 hrtimer_interrupt+0x2c0/0xb64 kernel/time/hrtimer.c:1815
 timer_handler drivers/clocksource/arm_arch_timer.c:674 [inline]
 arch_timer_handler_virt+0x74/0x88 drivers/clocksource/arm_arch_timer.c:685
 handle_percpu_devid_irq+0x2a4/0x804 kernel/irq/chip.c:942
 generic_handle_irq_desc include/linux/irqdesc.h:161 [inline]
 handle_irq_desc kernel/irq/irqdesc.c:672 [inline]
 generic_handle_domain_irq+0x7c/0xc4 kernel/irq/irqdesc.c:728
 __gic_handle_irq drivers/irqchip/irq-gic-v3.c:782 [inline]
 __gic_handle_irq_from_irqson drivers/irqchip/irq-gic-v3.c:833 [inline]
 gic_handle_irq+0x6c/0x190 drivers/irqchip/irq-gic-v3.c:877
 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:889
 do_interrupt_handler+0xd4/0x138 arch/arm64/kernel/entry-common.c:310
 __el1_irq arch/arm64/kernel/entry-common.c:536 [inline]
 el1_interrupt+0x34/0x68 arch/arm64/kernel/entry-common.c:551
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:556
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:594
 __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:27 [inline]
 arch_local_irq_enable+0x8/0xc arch/arm64/include/asm/irqflags.h:49
 cpuidle_idle_call kernel/sched/idle.c:170 [inline]
 do_idle+0x1f0/0x4e8 kernel/sched/idle.c:312
 cpu_startup_entry+0x5c/0x74 kernel/sched/idle.c:410
 rest_init+0x2dc/0x2f4 init/main.c:730
 start_kernel+0x0/0x4ec init/main.c:827
 start_kernel+0x3ec/0x4ec init/main.c:1072
 __primary_switched+0x84/0x8c arch/arm64/kernel/head.S:243
irq event stamp: 700776
hardirqs last  enabled at (700775): [<ffff80008ad6bc6c>] default_idle_call+0xf4/0x128 kernel/sched/idle.c:103
hardirqs last disabled at (700776): [<ffff80008ad66a78>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (700776): [<ffff80008ad66a78>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last  enabled at (700464): [<ffff80008002189c>] softirq_handle_end kernel/softirq.c:399 [inline]
softirqs last  enabled at (700464): [<ffff80008002189c>] __do_softirq+0xac8/0xce4 kernel/softirq.c:582
softirqs last disabled at (700459): [<ffff80008002ab48>] ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:81
---[ end trace 0000000000000000 ]---
rcu: __call_rcu_common(): Double-freed CB 000000007c840c9e->taprio_free_sched_cb+0x0/0x178()!!!   slab kmalloc-512 start ffff0000d010cc00 pointer offset 256 size 512

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/24 23:14 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 707081b61156 0ea90952 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in call_rcu
2024/03/30 01:15 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 707081b61156 c52bcb23 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in call_rcu
2023/12/17 07:53 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci d5b235ec8eab 3222d10c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in call_rcu
* Struck through repros no longer work on HEAD.