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INFO: rcu detected stall in preempt_schedule_thunk (3)

Status: auto-obsoleted due to no activity on 2026/04/07 23:53
Subsystems: kernel
[Documentation on labels]
First crash: 109d, last: 109d
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in preempt_schedule_thunk 1 1 709d 709d 0/3 auto-obsoleted due to no activity on 2024/08/25 23:34
linux-6.6 INFO: rcu detected stall in preempt_schedule_thunk 1 1 226d 226d 0/2 auto-obsoleted due to no activity on 2025/12/21 20:33
linux-6.6 INFO: rcu detected stall in preempt_schedule_thunk (2) 1 1 117d 117d 0/2 auto-obsoleted due to no activity on 2026/04/10 03:12
upstream INFO: rcu detected stall in preempt_schedule_thunk kernel 1 4 631d 672d 0/29 auto-obsoleted due to no activity on 2024/11/01 23:14
upstream INFO: rcu detected stall in preempt_schedule_thunk (2) kernel 1 2 495d 540d 0/29 auto-obsoleted due to no activity on 2025/03/18 05:25

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=cc0c/1/0x4000000000000000 softirq=70699/70704 fqs=5150
rcu: 	         hardirqs   softirqs   csw/system
rcu: 	 number:     6156          0            0
rcu: 	cputime:      269      52201            0   ==> 52480(ms)
rcu: 	(t=10500 jiffies g=59929 q=3613 ncpus=2)
CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:taprio_dequeue_tc_priority+0x284/0x750 net/sched/sch_taprio.c:-1
Code: 85 39 02 00 00 45 8b 36 89 df 44 89 f6 e8 84 aa 50 f8 44 39 f3 73 15 48 8b 5c 24 10 48 85 db 0f 85 7a 04 00 00 e8 ac a8 50 f8 <eb> 29 42 0f b6 44 25 00 84 c0 48 8b 5c 24 10 0f 85 8c 02 00 00 8b
RSP: 0018:ffffc90000007cd8 EFLAGS: 00000246
RAX: ffffffff89704f14 RBX: 0000000000000000 RCX: ffff88801c2f3d00
RDX: 0000000000000100 RSI: 0000000000000010 RDI: 000000000000000a
RBP: 1ffff1100b71146a R08: ffffffff896fa876 R09: ffffffff8df41aa0
R10: 0000000000000001 R11: ffffffff8962ec10 R12: dffffc0000000000
R13: ffff88805b88a354 R14: 0000000000000010 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff888125e1f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000005 CR3: 000000000dd3a000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 taprio_dequeue+0x186/0x550 net/sched/sch_taprio.c:-1
 dequeue_skb net/sched/sch_generic.c:297 [inline]
 qdisc_restart net/sched/sch_generic.c:402 [inline]
 __qdisc_run+0x23f/0x1510 net/sched/sch_generic.c:420
 qdisc_run+0xc7/0x300 include/net/pkt_sched.h:120
 net_tx_action+0x717/0x900 net/core/dev.c:5782
 handle_softirqs+0x22b/0x7c0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x60/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:finish_task_switch+0x242/0x940 kernel/sched/core.c:5114
Code: 0f 84 c2 01 00 00 48 85 db 0f 85 e9 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 c8 88 ca 09 e8 b3 10 37 00 fb 4c 8b 65 c0 <49> 8d bc 24 48 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc90000147a18 EFLAGS: 00000202
RAX: 0000000000476acb RBX: 0000000000000000 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8d792065 RDI: ffffffff8bc083e0
RBP: ffffc90000147a70 R08: ffffffff8f822277 R09: 1ffffffff1f0444e
R10: dffffc0000000000 R11: fffffbfff1f0444f R12: ffff88801c2f3d00
R13: dffffc0000000000 R14: ffff88802b728000 R15: ffff8880b863b498
 context_switch kernel/sched/core.c:5259 [inline]
 __schedule+0x14a3/0x4fd0 kernel/sched/core.c:6863
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7047
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 smpboot_thread_fn+0x5f9/0xa60 kernel/smpboot.c:159
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/07 23:49 net-next 8e7148b56023 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in preempt_schedule_thunk
* Struck through repros no longer work on HEAD.