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INFO: rcu detected stall in clone3 (5)

Status: auto-obsoleted due to no activity on 2025/03/30 08:38
Subsystems: mm
[Documentation on labels]
First crash: 409d, last: 199d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in clone3 mm 1 2 1283d 1309d 0/29 closed as invalid on 2022/02/08 10:10
linux-5.15 INFO: rcu detected stall in clone3 1 1 15d 15d 0/3 upstream: reported on 2025/07/02 10:02
upstream INFO: rcu detected stall in clone3 (2) kernfs 1 1 1131d 1131d 0/29 auto-closed as invalid on 2022/09/10 23:49
upstream INFO: rcu detected stall in clone3 (3) kernel 1 1 880d 880d 0/29 auto-obsoleted due to no activity on 2023/05/19 23:49
upstream INFO: rcu detected stall in clone3 (4) net mm 1 2 693d 773d 0/29 auto-obsoleted due to no activity on 2023/11/22 09:08

Sample crash report:
vkms_vblank_simulate: vblank timer overrun
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=3224/1/0x4000000000000000 softirq=97466/97474 fqs=830
rcu: 	(detected by 1, t=10502 jiffies, g=72865, q=805 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15273 Comm: syz.3.2173 Not tainted 6.13.0-rc4-syzkaller-00110-g4099a71718b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:timerqueue_add+0x33/0x330 lib/timerqueue.c:38
Code: 55 41 54 55 48 89 f5 53 48 83 ec 08 48 89 3c 24 e8 02 0b 74 f6 48 89 ea 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 <0f> 85 92 02 00 00 48 8b 5d 00 48 89 ee 48 89 df e8 88 0c 74 f6 48
RSP: 0018:ffffc90000007dc0 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff8880b862cb00 RCX: 0000000000000001
RDX: 1ffff1100fa1ea68 RSI: ffffffff8b260b1e RDI: ffff8880b862cb50
RBP: ffff88807d0f5340 R08: 0000000000000005 R09: 000000000000001f
R10: 0000000000000001 R11: 0000000000000001 R12: ffff8880b862ca00
R13: 0000000000000002 R14: ffff8880b862ca00 R15: ffffffff894158e0
FS:  000055558beff500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc6d73b4d58 CR3: 000000002ac4a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 enqueue_hrtimer+0x1c9/0x3c0 kernel/time/hrtimer.c:1084
 __run_hrtimer kernel/time/hrtimer.c:1756 [inline]
 __hrtimer_run_queues+0x903/0xae0 kernel/time/hrtimer.c:1803
 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194
Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 56 71 4a f6 48 89 df e8 ae f0 4a f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 95 d5 3b f6 65 8b 05 f6 90 d7 74 85 c0 74 16 5b
RSP: 0018:ffffc9000cf1fbb8 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffffffff8eea7b58 RCX: 1ffffffff20bde71
RDX: 0000000000000000 RSI: ffffffff8b6cd9e0 RDI: ffffffff8bd1ede0
RBP: 0000000000000202 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff905f36d7 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000202 R14: 0000000000000000 R15: ffff8880287f0000
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 add_device_randomness+0xb8/0xf0 drivers/char/random.c:949
 add_latent_entropy include/linux/random.h:26 [inline]
 kernel_clone+0x109/0x960 kernel/fork.c:2807
 __do_sys_clone3+0x1f9/0x270 kernel/fork.c:3110
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc6d95ba589
Code: 1b 08 00 48 8d 3d fc 1b 08 00 e8 12 29 f6 ff 66 90 b8 ea ff ff ff 48 85 ff 74 2c 48 85 d2 74 27 49 89 c8 b8 b3 01 00 00 0f 05 <48> 85 c0 7c 18 74 01 c3 31 ed 48 83 e4 f0 4c 89 c7 ff d2 48 89 c7
RSP: 002b:00007ffe7533f3c8 EFLAGS: 00000206 ORIG_RAX: 00000000000001b3
RAX: ffffffffffffffda RBX: 00007fc6d953c9a0 RCX: 00007fc6d95ba589
RDX: 00007fc6d953c9a0 RSI: 0000000000000058 RDI: 00007ffe7533f410
RBP: 00007fc6d73b46c0 R08: 00007fc6d73b46c0 R09: 00007ffe7533f4f7
R10: 0000000000000008 R11: 0000000000000206 R12: ffffffffffffffa8
R13: 000000000000006e R14: 00007ffe7533f410 R15: 00007ffe7533f4f8
 </TASK>
rcu: rcu_preempt kthread starved for 6794 jiffies! g72865 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:27488 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6848
 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.13.0-rc4-syzkaller-00110-g4099a71718b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline]
RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 d8 f4 d9 74 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 68 a1 b3 00 fb f4 <fa> c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc900001a7d58 EFLAGS: 00000246
RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8b29c759
RDX: 0000000000000001 RSI: ffff888020add800 RDI: ffff888020add864
RBP: ffff888020add864 R08: 0000000000000001 R09: ffffed10170e6fed
R10: ffff8880b8737f6b R11: 0000000000000000 R12: ffff88801d737800
R13: ffffffff8ee16a20 R14: 0000000000000001 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558b5065c8 CR3: 000000002ae50000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:699
 cpuidle_enter_state+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:268
 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:389
 cpuidle_idle_call kernel/sched/idle.c:230 [inline]
 do_idle+0x310/0x3f0 kernel/sched/idle.c:325
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423
 start_secondary+0x222/0x2b0 arch/x86/kernel/smpboot.c:314
 common_startup_64+0x13e/0x148
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/30 08:36 upstream 4099a71718b0 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in clone3
2024/12/13 02:44 upstream 150b567e0d57 3547e30f .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in clone3
2024/12/12 05:37 upstream 231825b2e1ff ff949d25 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in clone3
2024/10/09 09:10 upstream 75b607fab38d 402f1df0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in clone3
2024/09/28 05:44 upstream ad46e8f95e93 440b26ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in clone3
2024/07/25 21:42 upstream c33ffdb70cc6 32fcf98f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in clone3
2024/06/03 12:07 upstream c3f38fa61af7 0aba2352 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in clone3
* Struck through repros no longer work on HEAD.