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INFO: rcu detected stall in syscall_trace_enter (3)

Status: auto-obsoleted due to no activity on 2024/06/26 05:41
Subsystems: kernel
[Documentation on labels]
First crash: 498d, last: 498d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in syscall_trace_enter (2) mm 1 1 2075d 2075d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in syscall_trace_enter kernel 1 5 2496d 2520d 0/29 auto-closed as invalid on 2019/04/06 08:39
linux-6.6 INFO: rcu detected stall in syscall_trace_enter 1 1 22d 22d 0/2 upstream: reported on 2025/07/17 08:48
upstream INFO: rcu detected stall in syscall_trace_enter (4) trace bpf 1 10 158d 358d 0/29 auto-obsoleted due to no activity on 2025/06/01 11:19
linux-5.15 INFO: rcu detected stall in syscall_trace_enter origin:lts-only 1 syz inconclusive 36 11d 104d 0/3 upstream: reported syz repro on 2025/04/26 00:59

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=1e4c/1/0x4000000000000000 softirq=6110/6110 fqs=1
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5075/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=6525, q=775 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5189 Comm: syz-executor.0 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
RIP: 0010:check_preemption_disabled+0x0/0x120 lib/smp_processor_id.c:13
Code: c7 a0 fe fd 8b 48 c7 c6 e0 fe fd 8b eb 1c 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <41> 57 41 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89
RSP: 0018:ffffc90000007b18 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffc90000007b80 RCX: ffffffff81719934
RDX: 0000000000000000 RSI: ffffffff8baacec0 RDI: ffffffff8bfdff00
RBP: ffffc90000007c68 R08: ffffffff8f860def R09: 1ffffffff1f0c1bd
R10: dffffc0000000000 R11: fffffbfff1f0c1be R12: 1ffff92000000f6c
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000046
FS:  00007f641dfa76c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ff21000 CR3: 00000000110b2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 lockdep_recursion_inc kernel/locking/lockdep.c:462 [inline]
 lock_acquire+0x1a7/0x530 kernel/locking/lockdep.c:5753
 __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+0xab/0xca0 net/sched/sch_taprio.c:924
 __run_hrtimer kernel/time/hrtimer.c:1692 [inline]
 __hrtimer_run_queues+0x595/0xd00 kernel/time/hrtimer.c:1756
 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline]
 __sysvec_apic_timer_interrupt+0x107/0x3a0 arch/x86/kernel/apic/apic.c:1049
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:memset_orig+0x25/0xb0 arch/x86/lib/memset_64.S:61
Code: 90 90 90 90 90 66 0f 1f 00 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01 48 0f af c1 41 89 f9 41 83 e1 07 75 70 48 89 d1 <48> c1 e9 06 74 35 0f 1f 44 00 00 48 ff c9 48 89 07 48 89 47 08 48
RSP: 0018:ffffc900047c7798 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc900047c7820 RCX: 0000000000000018
RDX: 0000000000000018 RSI: 0000000000000000 RDI: ffffc900047c7820
RBP: ffffc900047c78b0 R08: ffffc900047c7837 R09: 0000000000000000
R10: ffffc900047c7820 R11: fffff520008f8f07 R12: ffffffff8baeaa06
R13: dffffc0000000000 R14: ffff0a01ffffff10 R15: ffff88805b8b90bc
 number+0xa2/0xf90 lib/vsprintf.c:461
 vsnprintf+0x1542/0x1da0 lib/vsprintf.c:2890
 audit_log_vformat+0x35c/0x9e0 kernel/audit.c:1977
 audit_log_format+0xdb/0x130 kernel/audit.c:2011
 audit_seccomp+0x19d/0x1f0 kernel/auditsc.c:3011
 seccomp_log kernel/seccomp.c:1003 [inline]
 __seccomp_filter+0xb1b/0x1fc0 kernel/seccomp.c:1292
 syscall_trace_enter+0xaa/0x150 kernel/entry/common.c:52
 syscall_enter_from_user_mode_work include/linux/entry-common.h:168 [inline]
 syscall_enter_from_user_mode include/linux/entry-common.h:198 [inline]
 do_syscall_64+0xcc/0x240 arch/x86/entry/common.c:79
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f641d27dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f641dfa7178 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f641d3abf88 RCX: 00007f641d27dda9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f641d3abf88
RBP: 00007f641d3abf80 R08: 00007f641dfa76c0 R09: 00007f641dfa76c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f641d3abf8c
R13: 000000000000000b R14: 00007ffd7350e5a0 R15: 00007ffd7350e688
 </TASK>
task:syz-executor.3  state:R  running task     stack:19312 pid:5075  tgid:5075  ppid:5064   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5409 [inline]
 __schedule+0x1781/0x49d0 kernel/sched/core.c:6736
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6915
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6939
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 copy_pte_range mm/memory.c:1126 [inline]
 copy_pmd_range mm/memory.c:1187 [inline]
 copy_pud_range mm/memory.c:1224 [inline]
 copy_p4d_range mm/memory.c:1248 [inline]
 copy_page_range+0x3763/0x4240 mm/memory.c:1346
 dup_mmap kernel/fork.c:747 [inline]
 dup_mm kernel/fork.c:1687 [inline]
 copy_mm+0x12f5/0x21b0 kernel/fork.c:1736
 copy_process+0x187a/0x3df0 kernel/fork.c:2389
 kernel_clone+0x223/0x840 kernel/fork.c:2796
 __do_sys_clone kernel/fork.c:2939 [inline]
 __se_sys_clone kernel/fork.c:2923 [inline]
 __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2923
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fddf7a7add3
RSP: 002b:00007ffe4592c318 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fddf7a7add3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000555561c46750 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g6525 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:26256 pid:16    tgid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5409 [inline]
 __schedule+0x1781/0x49d0 kernel/sched/core.c:6736
 __schedule_loop kernel/sched/core.c:6813 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6828
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2572
 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:1663
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1862
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 10 Comm: kworker/u8:0 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0x1859/0x2960 kernel/smp.c:855
Code: 01 31 ff e8 d9 d5 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 84 d1 0b 00 eb 38 f3 90 42 0f b6 04 23 84 c0 75 11 <41> f7 45 00 01 00 00 00 74 1e e8 68 d1 0b 00 eb e4 44 89 e9 80 e1
RSP: 0018:ffffc900000f76e0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff11017288be5 RCX: ffff888017299e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900000f78e0 R08: ffffffff818922b7 R09: 1ffffffff2595ca0
R10: dffffc0000000000 R11: fffffbfff2595ca1 R12: dffffc0000000000
R13: ffff8880b9445f28 R14: ffff8880b953f440 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7c6517e1f8 CR3: 000000000df32000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2086 [inline]
 text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2296
 text_poke_flush arch/x86/kernel/alternative.c:2487 [inline]
 text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2494
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:205
 static_key_enable+0x1a/0x20 kernel/jump_label.c:218
 toggle_allocation_gate+0xb5/0x250 mm/kfence/core.c:826
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/28 05:32 upstream fe46a7dd189e 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in syscall_trace_enter
* Struck through repros no longer work on HEAD.