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INFO: rcu detected stall in tty_release (3)

Status: auto-obsoleted due to no activity on 2025/11/19 23:52
Subsystems: net bluetooth
[Documentation on labels]
First crash: 219d, last: 163d
Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in tty_release (2) mm 1 4 361d 452d 0/29 auto-obsoleted due to no activity on 2025/05/06 09:10
upstream INFO: rcu detected stall in tty_release serial 1 3 564d 632d 0/29 auto-obsoleted due to no activity on 2024/10/15 04:06

Sample crash report:
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=b204/1/0x4000000000000000 softirq=183815/183816 fqs=143
rcu: 	(detected by 1, t=10502 jiffies, g=154117, q=145 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 22349 Comm: syz.5.3221 Not tainted 6.16.0-rc3-syzkaller-00190-g67a993863163 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:kasan_check_range+0xd/0x2c0 mm/kasan/generic.c:188
Code: 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 49 39 f8 0f 82 82
RSP: 0018:ffffc90000007c18 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff99c72400 RCX: ffffffff819eca4d
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff99c72400
RBP: ffffc90000007d08 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f70 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff99c72404 R15: 1ffff92000000f90
FS:  00007f306c3976c0(0000) GS:ffff888125c50000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c291dfc CR3: 000000005eef1000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
 queued_spin_is_locked include/asm-generic/qspinlock.h:57 [inline]
 debug_spin_unlock kernel/locking/spinlock_debug.c:101 [inline]
 do_raw_spin_unlock+0x4d/0x240 kernel/locking/spinlock_debug.c:141
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_unlock_irqrestore+0x78/0x110 kernel/locking/spinlock.c:194
 debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline]
 debug_deactivate+0x1d/0x200 kernel/time/hrtimer.c:490
 __run_hrtimer kernel/time/hrtimer.c:1729 [inline]
 __hrtimer_run_queues+0x2b0/0xc60 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:arch_stack_walk+0x112/0x150 arch/x86/kernel/stacktrace.c:27
Code: ff ff 00 74 38 4c 8d bd 78 ff ff ff 4c 89 ff e8 64 1b 09 00 48 85 c0 74 24 48 89 df 48 89 c6 4d 89 f3 2e e8 10 5a 00 0a 84 c0 <74> 11 4c 89 ff e8 94 1c 09 00 83 bd 78 ff ff ff 00 75 cf 65 48 8b
RSP: 0018:ffffc9000489f308 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc9000489f3c0 RCX: 3b133dbd3bb8d300
RDX: dffffc0000000000 RSI: ffffffff81aaf755 RDI: ffffc9000489f3c0
RBP: ffffc9000489f390 R08: ffffc9000489f3d0 R09: 000000000000000e
R10: dffffc0000000000 R11: ffffffff81ace6a0 R12: ffff8880306e9e00
R13: dffffc0000000000 R14: ffffffff81ace6a0 R15: ffffc9000489f308
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 ref_tracker_free+0xef/0x7d0 lib/ref_tracker.c:239
 netdev_tracker_free include/linux/netdevice.h:4361 [inline]
 netdev_put include/linux/netdevice.h:4378 [inline]
 in_dev_finish_destroy+0x9b/0x190 net/ipv4/devinet.c:258
 in_dev_put include/linux/inetdevice.h:290 [inline]
 inetdev_destroy net/ipv4/devinet.c:338 [inline]
 inetdev_event+0x81c/0x15b0 net/ipv4/devinet.c:1656
 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline]
 call_netdevice_notifiers net/core/dev.c:2282 [inline]
 unregister_netdevice_many_notify+0x15d8/0x2320 net/core/dev.c:12077
 unregister_netdevice_many net/core/dev.c:12140 [inline]
 unregister_netdevice_queue+0x33c/0x380 net/core/dev.c:11984
 unregister_netdevice include/linux/netdevice.h:3379 [inline]
 unregister_netdev+0x1f/0x60 net/core/dev.c:12158
 tty_ldisc_kill+0xa3/0x1a0 drivers/tty/tty_ldisc.c:613
 tty_ldisc_release+0x1a4/0x200 drivers/tty/tty_ldisc.c:781
 tty_release_struct+0x2a/0xd0 drivers/tty/tty_io.c:1681
 tty_release+0xcb0/0x1640 drivers/tty/tty_io.c:1852
 __fput+0x44c/0xa70 fs/file_table.c:465
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 get_signal+0x11ed/0x1340 kernel/signal.c:2807
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f306b58e929
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:00007f306c397038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f306b7b5fa0 RCX: 00007f306b58e929
RDX: 0000200000000000 RSI: 0000000000005423 RDI: 0000000000000003
RBP: 00007f306b610b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f306b7b5fa0 R15: 00007ffcab489428
 </TASK>
rcu: rcu_preempt kthread starved for 10215 jiffies! g154117 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:26464 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6878
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
 kthread+0x711/0x8a0 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:
CPU: 1 UID: 0 PID: 19051 Comm: syz-executor Not tainted 6.16.0-rc3-syzkaller-00190-g67a993863163 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: 8b 3d c4 35 fa 0b 48 89 de 5b e9 73 bc 58 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 08 00 9d 92 65 8b 15 a8 b1 dc 10 81 e2 00 01 ff 00
RSP: 0000:ffffc90003bdf718 EFLAGS: 00000202
RAX: ffffffff81b4d920 RBX: ffff8880b873b1c0 RCX: ffff88802f151e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003bdf880 R08: ffffffff8fa109f7 R09: 1ffffffff1f4213e
R10: dffffc0000000000 R11: fffffbfff1f4213f R12: 1ffff110170c8385
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641c28
FS:  0000555585e5b500(0000) GS:ffff888125d50000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555585e765c8 CR3: 000000005b10b000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 csd_lock_wait kernel/smp.c:340 [inline]
 smp_call_function_many_cond+0xf80/0x12d0 kernel/smp.c:885
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
 flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
 flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
 ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
 wp_page_copy mm/memory.c:3635 [inline]
 do_wp_page+0x1bc2/0x5800 mm/memory.c:4030
 handle_pte_fault mm/memory.c:6085 [inline]
 __handle_mm_fault+0x1144/0x5620 mm/memory.c:6212
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6381
 do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
 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: 0033:0x7effa4b4cd9f
Code: 8d 34 19 48 39 d5 48 89 75 60 0f 95 c2 48 29 d8 48 83 c1 10 0f b6 d2 48 83 c8 01 48 c1 e2 02 48 09 da 48 83 ca 01 48 89 51 f8 <48> 89 46 08 eb 80 48 8d 0d 61 d3 0e 00 48 8d 15 65 e5 0e 00 bf 01
RSP: 002b:00007ffc6dd55610 EFLAGS: 00010206
RAX: 0000000000018a41 RBX: 0000000000008040 RCX: 0000555585e6e590
RDX: 0000000000008041 RSI: 0000555585e765c0 RDI: 0000000000000004
RBP: 00007effa4d84ca0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000802 R12: 0000000000008030
R13: 0000000000000076 R14: 00007effa4d84d00 R15: 0000000000000000
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/27 13:16 upstream 67a993863163 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in tty_release
2025/08/21 23:52 linux-next 7fa4d8dc380f bf27483f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in tty_release
* Struck through repros no longer work on HEAD.