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INFO: rcu detected stall in mrp_join_timer

Status: upstream: reported on 2024/08/09 18:10
Reported-by: syzbot+108b85b9138bd2044120@syzkaller.appspotmail.com
First crash: 49d, last: 49d
▶ ▼ Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: rcu detected stall in mrp_join_timer 7 1562d 1727d 0/1 auto-closed as invalid on 2020/10/17 01:22
upstream INFO: rcu detected stall in mrp_join_timer net 1 1725d 1724d 0/28 closed as invalid on 2020/01/09 08:13
linux-4.19 INFO: rcu detected stall in mrp_join_timer 28 1412d 1725d 0/1 auto-closed as invalid on 2021/03/15 12:15
upstream INFO: rcu detected stall in mrp_join_timer (3) net 1 283d 283d 0/28 closed as invalid on 2024/02/01 10:31
upstream INFO: rcu detected stall in mrp_join_timer (2) net 57 936d 1686d 0/28 auto-closed as invalid on 2022/07/04 18:27
linux-4.14 BUG: soft lockup in mrp_join_timer 1 1285d 1285d 0/1 auto-closed as invalid on 2021/07/20 15:25
upstream BUG: soft lockup in mrp_join_timer (2) net 1 362d 362d 0/28 closed as invalid on 2023/11/01 18:32
linux-4.19 BUG: soft lockup in mrp_join_timer (2) 58 583d 1260d 0/1 upstream: reported on 2021/04/16 18:29

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4179
	(detected by 1, t=10502 jiffies, g=9573, q=1077 ncpus=2)
task:syz.4.72        state:R  running task     stack:23184 pid:4179  ppid:3923   flags:0x00004008
Call Trace:
 <IRQ>
 sched_show_task+0x4d5/0x670 kernel/sched/core.c:8942
 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:261 [inline]
 print_other_cpu_stall+0x1299/0x1640 kernel/rcu/tree_stall.h:606
 check_cpu_stall kernel/rcu/tree_stall.h:778 [inline]
 rcu_pending kernel/rcu/tree.c:3890 [inline]
 rcu_sched_clock_irq+0xaf6/0x1200 kernel/rcu/tree.c:2393
 update_process_times+0x147/0x1b0 kernel/time/timer.c:1869
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1501
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x5a7/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x3e/0xb0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:get_random_u32+0x59b/0xaa0
Code: 4c 21 f3 0f 85 96 00 00 00 e8 41 80 d5 fc 48 8b 5c 24 20 4d 85 ff 75 07 e8 32 80 d5 fc eb 06 e8 2b 80 d5 fc fb 48 8b 44 24 28 <42> 0f b6 04 28 84 c0 0f 85 91 01 00 00 8b 84 24 60 01 00 00 48 c7
RSP: 0018:ffffc900001e0a00 EFLAGS: 00000246
RAX: 1ffff9200003c16c RBX: 1ffff9200003c148 RCX: ffff8880212b3b80
RDX: 0000000000000102 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900001e0be0 R08: ffffffff84b52051 R09: fffffbfff20e7260
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff11017326ef5
R13: dffffc0000000000 R14: 0000000000000046 R15: 0000000000000200
 __get_random_u32_below+0x10/0x90 drivers/char/random.c:527
 get_random_u32_below include/linux/random.h:64 [inline]
 prandom_u32_max include/linux/prandom.h:29 [inline]
 mrp_join_timer_arm net/802/mrp.c:595 [inline]
 mrp_join_timer+0x112/0x180 net/802/mrp.c:611
 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1504
 expire_timers kernel/time/timer.c:1549 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1820
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833
 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
 do_softirq+0x162/0x240 kernel/softirq.c:472
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x1b1/0x1f0 kernel/softirq.c:396
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:861 [inline]
 __dev_queue_xmit+0x1790/0x3cf0 net/core/dev.c:4320
 dev_queue_xmit include/linux/netdevice.h:3021 [inline]
 __bpf_tx_skb net/core/filter.c:2125 [inline]
 __bpf_redirect_common net/core/filter.c:2173 [inline]
 __bpf_redirect+0xbb1/0x1180 net/core/filter.c:2180
 ____bpf_clone_redirect net/core/filter.c:2453 [inline]
 bpf_clone_redirect+0x266/0x3c0 net/core/filter.c:2425
 bpf_prog_c6f54bbad6dab1ee+0x56/0x5b
 bpf_dispatcher_nop_func include/linux/bpf.h:989 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 bpf_test_run+0x40f/0x8b0 net/bpf/test_run.c:402
 bpf_prog_test_run_skb+0xaf1/0x13a0 net/bpf/test_run.c:1186
 bpf_prog_test_run+0x32f/0x3a0 kernel/bpf/syscall.c:3685
 __sys_bpf+0x3eb/0x6c0 kernel/bpf/syscall.c:5038
 __do_sys_bpf kernel/bpf/syscall.c:5124 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5122 [inline]
 __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5122
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbf0df779f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbf0ece6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fbf0e105f80 RCX: 00007fbf0df779f9
RDX: 0000000000000050 RSI: 0000000020000080 RDI: 000000000000000a
RBP: 00007fbf0dfe58ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fbf0e105f80 R15: 00007ffe13362868
 </TASK>
rcu: rcu_preempt kthread starved for 10550 jiffies! g9573 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:26144 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 34 Comm: kworker/u4:2 Not tainted 6.1.103-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0x1fb0/0x3460 kernel/smp.c:998
Code: 2f 44 89 ee 83 e6 01 31 ff e8 4c 40 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 d7 3c 0b 00 e9 1b ff ff ff f3 90 <42> 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff
RSP: 0018:ffffc90000ab75a0 EFLAGS: 00000293
RAX: ffffffff817f63eb RBX: 1ffff110173281b1 RCX: ffff888016aabb80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000ab7980 R08: ffffffff817f63b4 R09: fffffbfff20e7245
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b9940d88
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000008000002b7 CR3: 000000000d08e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1334 [inline]
 text_poke_bp_batch+0x2bb/0x940 arch/x86/kernel/alternative.c:1534
 text_poke_flush arch/x86/kernel/alternative.c:1725 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1732
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x12e/0x250 kernel/jump_label.c:205
 static_key_enable+0x16/0x20 kernel/jump_label.c:218
 toggle_allocation_gate+0xbf/0x480 mm/kfence/core.c:804
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/09 18:10 linux-6.1.y 48d525b0e463 a83d9288 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in mrp_join_timer
* Struck through repros no longer work on HEAD.