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INFO: rcu detected stall in schedule_tail (7)

Status: auto-obsoleted due to no activity on 2025/08/22 04:05
Subsystems: mm
[Documentation on labels]
First crash: 183d, last: 183d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in schedule_tail (4) arm 1 2 931d 1008d 0/29 auto-obsoleted due to no activity on 2023/09/05 02:08
linux-6.1 INFO: rcu detected stall in schedule_tail 1 1 528d 528d 0/3 auto-obsoleted due to no activity on 2024/10/21 04:18
upstream INFO: rcu detected stall in schedule_tail mm 1 145 2211d 2213d 0/29 closed as invalid on 2019/12/04 14:14
upstream INFO: rcu detected stall in schedule_tail (3) cgroups mm 1 40 2176d 2176d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in schedule_tail (5) mm 1 2 802d 804d 0/29 auto-obsoleted due to no activity on 2024/01/11 06:31
upstream INFO: rcu detected stall in schedule_tail (6) mm 1 C 8 351d 446d 0/29 auto-obsoleted due to no activity on 2025/04/16 03:50
upstream INFO: rcu detected stall in schedule_tail (2) mm 1 26 2176d 2177d 0/29 closed as invalid on 2020/01/08 05:23

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P64/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=63493, q=236 ncpus=2)
task:kworker/u8:4    state:R  running task     stack:20792 pid:64    tgid:64    ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5313 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6696
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7019
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:lock_release+0x2b5/0x3e0 kernel/locking/lockdep.c:5896
Code: 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 75 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 4b 58 01 11 <48> 3b 44 24 28 0f 85 8b 00 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000213f9b8 EFLAGS: 00000206
RAX: 10df0f53619cfb00 RBX: 0000000000000202 RCX: 10df0f53619cfb00
RDX: 0000000000000002 RSI: ffffffff8db7f40a RDI: ffffffff8be320a0
RBP: ffff88801c7cc740 R08: 0000000000000000 R09: ffffffff8b3b2162
R10: dffffc0000000000 R11: ffffffff8b3b2090 R12: 0000000000000002
R13: 0000000000000002 R14: ffffffff8e13ef20 R15: ffff88801c7cbc00
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock include/linux/rcupdate.h:871 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0x28c/0x610 net/batman-adv/network-coding.c:719
 process_one_work kernel/workqueue.c:3239 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3322
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g63493 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=48425
rcu: rcu_preempt kthread starved for 10503 jiffies! g63493 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
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:I stack:27128 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5313 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6696
 __schedule_loop kernel/sched/core.c:6774 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6789
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2060
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2262
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 13648 Comm: syz-executor Not tainted 6.16.0-rc2-next-20250620-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline]
RIP: 0010:lock_acquire+0x58/0x360 kernel/locking/lockdep.c:5834
Code: 8b 05 fc 6b 01 11 48 89 44 24 58 0f 1f 44 00 00 65 8b 05 ff 6b 01 11 83 f8 08 0f 83 b8 01 00 00 89 c0 48 0f a3 05 a8 5f 03 0e <73> 16 e8 91 f3 08 00 84 c0 75 0d f6 05 85 57 ed 0d 01 0f 84 d7 01
RSP: 0018:ffffc90000a08bc0 EFLAGS: 00000097
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88803289b300
RBP: ffffffff898cbc94 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff898cbbd0 R12: 0000000000000000
R13: ffff88803289b300 R14: 0000000000000000 R15: 0000000000000001
FS:  00005555713e8500(0000) GS:ffff888125d26000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555713e87d0 CR3: 000000007dfac000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0xc4/0xc90 net/sched/sch_taprio.c:924
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:kasan_check_range+0x7/0x2c0 mm/kasan/generic.c:188
Code: e8 7e f7 e3 ff 90 0f 0b cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 41 57 <41> 56 41 55 41 54 53 b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d 04 37
RSP: 0018:ffffc90011e2f7b0 EFLAGS: 00000293
RAX: ffffffff82123be7 RBX: ffffea00013c52c0 RCX: ffffffff82123bf4
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffea00013c52c0
RBP: 0000000000000000 R08: ffffea00013c52f3 R09: 1ffffd4000278a5e
R10: dffffc0000000000 R11: fffff94000278a5f R12: dffffc0000000000
R13: ffffea00013c52f0 R14: 00fff00000020008 R15: 00005555713e8000
 instrument_atomic_write include/linux/instrumented.h:82 [inline]
 set_bit include/asm-generic/bitops/instrumented-atomic.h:28 [inline]
 SetPageAnonExclusive include/linux/page-flags.h:1158 [inline]
 folio_add_new_anon_rmap+0x5a4/0x1a80 mm/rmap.c:1575
 wp_page_copy mm/memory.c:3654 [inline]
 do_wp_page+0x1bfe/0x5800 mm/memory.c:4048
 handle_pte_fault mm/memory.c:6103 [inline]
 __handle_mm_fault+0x1144/0x5620 mm/memory.c:6230
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6399
 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:__put_user_4+0xd/0x20 arch/x86/lib/putuser.S:94
Code: 66 89 01 31 c9 0f 01 ca e9 50 3a 03 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 89 cb 48 c1 fb 3f 48 09 d9 0f 01 cb <89> 01 31 c9 0f 01 ca c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90011e2fe48 EFLAGS: 00050202
RAX: 0000000000000654 RBX: 0000000000000000 RCX: 00005555713e87d0
RDX: 0000000000000000 RSI: ffffffff8db7f40a RDI: ffff88802cf08000
RBP: ffffc90011e2ff48 R08: 0000000000000000 R09: ffffffff818d1638
R10: dffffc0000000000 R11: fffffbfff1f4327f R12: 1ffff110059e10d4
R13: 1ffff920023c5fd4 R14: ffff88802cf08000 R15: dffffc0000000000
 schedule_tail+0xa3/0xc0 kernel/sched/core.c:5248
 ret_from_fork+0x92/0x770 arch/x86/kernel/process.c:144
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/23 03:59 linux-next 5d4809e25903 d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in schedule_tail
* Struck through repros no longer work on HEAD.