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INFO: rcu detected stall in tun_chr_close (5)

Status: auto-obsoleted due to no activity on 2023/09/01 17:23
Subsystems: net
[Documentation on labels]
First crash: 337d, last: 337d
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in tun_chr_close (3) netfilter 1 1378d 1378d 0/26 auto-closed as invalid on 2020/10/25 04:38
upstream INFO: rcu detected stall in tun_chr_close (2) netfilter 1 1519d 1519d 0/26 closed as invalid on 2020/05/30 17:14
upstream INFO: rcu detected stall in tun_chr_close (4) bpf net 3 839d 909d 0/26 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in tun_chr_close net 13 1973d 2054d 0/26 auto-closed as invalid on 2019/06/08 11:01
linux-5.15 INFO: rcu detected stall in tun_chr_close 1 113d 113d 0/3 auto-obsoleted due to no activity on 2024/04/23 00:30
android-5-15 BUG: soft lockup in tun_chr_close 2 8d02h 15d 0/2 premoderation: reported on 2024/04/20 23:17

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=7d34/1/0x4000000000000000 softirq=119935/119936 fqs=0
rcu: 	(t=10500 jiffies g=144713 q=106 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g144713 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=100378
rcu: rcu_preempt kthread starved for 10500 jiffies! g144713 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28232 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5343 [inline]
 __schedule+0xc9a/0x5880 kernel/sched/core.c:6669
 schedule+0xde/0x1a0 kernel/sched/core.c:6745
 schedule_timeout+0x14e/0x2b0 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x190/0x910 kernel/rcu/tree.c:1609
 rcu_gp_kthread+0x23a/0x360 kernel/rcu/tree.c:1808
 kthread+0x344/0x440 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </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: 29708 Comm: kworker/0:9 Not tainted 6.4.0-rc4-syzkaller-00268-g51f269a6ecc7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:list_add_tail include/linux/list.h:102 [inline]
RIP: 0010:list_move_tail include/linux/list.h:230 [inline]
RIP: 0010:fq_pie_qdisc_dequeue+0x6f2/0x9c0 net/sched/sch_fq_pie.c:248
Code: 03 42 80 3c 20 00 0f 85 b9 02 00 00 4d 89 7d 00 e8 73 3b 45 f9 48 8d 85 e8 02 00 00 48 89 44 24 08 48 c1 e8 03 42 80 3c 20 00 <0f> 85 4e 02 00 00 4c 8b ad e8 02 00 00 48 89 df 48 8b 14 24 4c 89
RSP: 0018:ffffc900054ff588 EFLAGS: 00000246
RAX: 1ffff11004fc5a5d RBX: ffff8880472455a0 RCX: 0000000000000000
RDX: ffff8880439d8000 RSI: ffffffff883f0acd RDI: ffff888027e2d2e8
RBP: ffff888027e2d000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 1600000000000000 R12: dffffc0000000000
R13: ffff888027e2d2e0 R14: ffff888027e2d2f0 R15: ffff888027e2d2e0
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2db30000 CR3: 00000000480cd000 CR4: 0000000000350ef0
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 dequeue_skb net/sched/sch_generic.c:292 [inline]
 qdisc_restart net/sched/sch_generic.c:397 [inline]
 __qdisc_run+0x1b2/0x1780 net/sched/sch_generic.c:415
 __dev_xmit_skb net/core/dev.c:3868 [inline]
 __dev_queue_xmit+0x2215/0x3b10 net/core/dev.c:4210
 dev_queue_xmit include/linux/netdevice.h:3085 [inline]
 neigh_connected_output+0x3c2/0x550 net/core/neighbour.c:1581
 neigh_output include/net/neighbour.h:544 [inline]
 ip6_finish_output2+0x55a/0x1560 net/ipv6/ip6_output.c:134
 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
 ip6_finish_output+0x69a/0x1170 net/ipv6/ip6_output.c:206
 NF_HOOK_COND include/linux/netfilter.h:292 [inline]
 ip6_output+0x1f1/0x540 net/ipv6/ip6_output.c:227
 dst_output include/net/dst.h:458 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 NF_HOOK include/linux/netfilter.h:297 [inline]
 mld_sendpack+0xa09/0xed0 net/ipv6/mcast.c:1820
 mld_send_initial_cr.part.0+0x1a6/0x260 net/ipv6/mcast.c:2239
 mld_send_initial_cr net/ipv6/mcast.c:1232 [inline]
 ipv6_mc_dad_complete+0x1d4/0x680 net/ipv6/mcast.c:2247
 addrconf_dad_completed+0xa01/0xe00 net/ipv6/addrconf.c:4234
 addrconf_dad_begin net/ipv6/addrconf.c:4019 [inline]
 addrconf_dad_work+0x820/0x1390 net/ipv6/addrconf.c:4121
 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405
 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552
 kthread+0x344/0x440 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 29708 Comm: kworker/0:9 Not tainted 6.4.0-rc4-syzkaller-00268-g51f269a6ecc7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:write_comp_data+0x3f/0x90 kernel/kcov.c:236
Code: 49 89 f8 65 48 8b 14 25 c0 bb 03 00 a9 00 01 ff 00 74 0e 85 f6 74 59 8b 82 0c 16 00 00 85 c0 74 4f 8b 82 e8 15 00 00 83 f8 03 <75> 44 48 8b 82 f0 15 00 00 8b 92 ec 15 00 00 48 8b 38 48 c1 e2 03
RSP: 0018:ffffc900054ff580 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880472455a0 RCX: ffffffff883f0a5f
RDX: ffff8880439d8000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff888027e2d000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 1600000000000000 R12: dffffc0000000000
R13: 0000000000000001 R14: ffff888027e2d2f0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2db30000 CR3: 00000000480cd000 CR4: 0000000000350ef0
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __list_del_entry include/linux/list.h:134 [inline]
 list_move_tail include/linux/list.h:229 [inline]
 fq_pie_qdisc_dequeue+0x66f/0x9c0 net/sched/sch_fq_pie.c:248
 dequeue_skb net/sched/sch_generic.c:292 [inline]
 qdisc_restart net/sched/sch_generic.c:397 [inline]
 __qdisc_run+0x1b2/0x1780 net/sched/sch_generic.c:415
 __dev_xmit_skb net/core/dev.c:3868 [inline]
 __dev_queue_xmit+0x2215/0x3b10 net/core/dev.c:4210
 dev_queue_xmit include/linux/netdevice.h:3085 [inline]
 neigh_connected_output+0x3c2/0x550 net/core/neighbour.c:1581
 neigh_output include/net/neighbour.h:544 [inline]
 ip6_finish_output2+0x55a/0x1560 net/ipv6/ip6_output.c:134
 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
 ip6_finish_output+0x69a/0x1170 net/ipv6/ip6_output.c:206
 NF_HOOK_COND include/linux/netfilter.h:292 [inline]
 ip6_output+0x1f1/0x540 net/ipv6/ip6_output.c:227
 dst_output include/net/dst.h:458 [inline]
 NF_HOOK include/linux/netfilter.h:303 [inline]
 NF_HOOK include/linux/netfilter.h:297 [inline]
 mld_sendpack+0xa09/0xed0 net/ipv6/mcast.c:1820
 mld_send_initial_cr.part.0+0x1a6/0x260 net/ipv6/mcast.c:2239
 mld_send_initial_cr net/ipv6/mcast.c:1232 [inline]
 ipv6_mc_dad_complete+0x1d4/0x680 net/ipv6/mcast.c:2247
 addrconf_dad_completed+0xa01/0xe00 net/ipv6/addrconf.c:4234
 addrconf_dad_begin net/ipv6/addrconf.c:4019 [inline]
 addrconf_dad_work+0x820/0x1390 net/ipv6/addrconf.c:4121
 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405
 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552
 kthread+0x344/0x440 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
CPU: 1 PID: 4466 Comm: syz-executor.1 Not tainted 6.4.0-rc4-syzkaller-00268-g51f269a6ecc7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:kvm_wait+0xa8/0x110 arch/x86/kernel/kvm.c:1064
Code: fa 83 e2 07 38 d0 7f 04 84 c0 75 66 0f b6 07 40 38 c6 74 1b 48 83 c4 10 c3 c3 e8 53 9f 52 00 eb 07 0f 00 2d 0a 47 11 09 fb f4 <48> 83 c4 10 c3 eb 07 0f 00 2d fa 46 11 09 f4 48 83 c4 10 c3 89 74
RSP: 0018:ffffc900001e0b48 EFLAGS: 00000202
RAX: 000000000000b7bc RBX: 0000000000000000 RCX: 1ffffffff22ae156
RDX: 0000000000000000 RSI: 0000000000000102 RDI: 0000000000000000
RBP: ffff888027e2d0f0 R08: 0000000000000001 R09: ffffffff91528dbf
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: ffffed1004fc5a1e R14: 0000000000000001 R15: ffff8880b993d440
FS:  0000555556a7e400(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbd0c7831b8 CR3: 000000004039b000 CR4: 0000000000350ee0
Call Trace:
 <IRQ>
 pv_wait arch/x86/include/asm/paravirt.h:598 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x8cb/0xb50 kernel/locking/qspinlock.c:511
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:586 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x204/0x2b0 kernel/locking/spinlock_debug.c:115
 spin_lock include/linux/spinlock.h:350 [inline]
 fq_pie_timer+0x96/0x2a0 net/sched/sch_fq_pie.c:377
 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700
 expire_timers+0x29b/0x4b0 kernel/time/timer.c:1751
 __run_timers kernel/time/timer.c:2022 [inline]
 __run_timers kernel/time/timer.c:1995 [inline]
 run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035
 __do_softirq+0x1d4/0x905 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__kasan_check_read+0x0/0x20 mm/kasan/shadow.c:30
Code: 89 54 24 08 0f 85 4a ff ff ff e9 1b fe ff ff 48 83 c4 60 4c 89 c6 48 c7 c7 00 19 f1 8b 5b 5d 41 5c e9 e4 14 91 ff 0f 1f 40 00 <f3> 0f 1e fa 48 8b 0c 24 89 f6 31 d2 e9 2f f4 ff ff 66 66 2e 0f 1f
RSP: 0018:ffffc90014fe7c20 EFLAGS: 00000246
RAX: 0000000000004000 RBX: ffffffff8e1151c0 RCX: 1ffffffff18c0e14
RDX: fffffbfff1c22a39 RSI: 0000000000000008 RDI: ffffffff8e1151c0
RBP: ffff8880439d8000 R08: 0000000000000000 R09: ffffffff8e1151c7
R10: fffffbfff1c22a38 R11: 0000000000000001 R12: 0000000000000000
R13: ffffed10029d83b8 R14: ffff888014ec1dc0 R15: dffffc0000000000
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 atomic_long_read include/linux/atomic/atomic-instrumented.h:1309 [inline]
 __mutex_owner kernel/locking/mutex.c:81 [inline]
 mutex_spin_on_owner+0x8c/0x2e0 kernel/locking/mutex.c:359
 mutex_optimistic_spin kernel/locking/mutex.c:476 [inline]
 __mutex_lock_common kernel/locking/mutex.c:694 [inline]
 __mutex_lock+0xd97/0x1350 kernel/locking/mutex.c:747
 tun_detach drivers/net/tun.c:697 [inline]
 tun_chr_close+0x3e/0x240 drivers/net/tun.c:3491
 __fput+0x27c/0xa90 fs/file_table.c:321
 task_work_run+0x16f/0x270 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297
 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fbffde3e01b
Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44
RSP: 002b:00007fffa7f58620 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007fbffde3e01b
RDX: 0000000000000000 RSI: 0000001b2d7256f0 RDI: 0000000000000003
RBP: 00007fbffdfad980 R08: 0000000000000000 R09: 0000000097e68176
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000022732f
R13: 00007fffa7f58720 R14: 00007fbffdfac050 R15: 0000000000000032
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/03 17:19 upstream 51f269a6ecc7 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in tun_chr_close
* Struck through repros no longer work on HEAD.