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INFO: rcu detected stall in dput (3)

Status: upstream: reported on 2024/12/09 17:03
Reported-by: syzbot+593324eabd9eef11e831@syzkaller.appspotmail.com
First crash: 108d, last: 16d
▶ ▼ Similar bugs (11)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in dput (2) 26 1d10h 303d 0/3 upstream: reported on 2024/05/28 13:43
upstream INFO: rcu detected stall in dput (4) kvm C error error 2 1204d 1563d 0/28 closed as invalid on 2022/02/08 10:37
upstream INFO: rcu detected stall in dput (3) kernel 1 1906d 1906d 0/28 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in dput (8) mm fs C done 298 1d00h 452d 0/28 upstream: reported C repro on 2023/12/31 19:35
linux-5.15 INFO: rcu detected stall in dput 2 576d 616d 0/3 auto-obsoleted due to no activity on 2023/12/08 00:28
upstream INFO: rcu detected stall in dput (6) fs 2 877d 937d 0/28 auto-obsoleted due to no activity on 2023/01/16 04:13
linux-5.15 INFO: rcu detected stall in dput (2) 10 236d 377d 0/3 auto-obsoleted due to no activity on 2024/11/12 09:55
upstream INFO: rcu detected stall in dput (5) fs 1 1074d 1074d 0/28 auto-closed as invalid on 2022/07/18 12:41
linux-6.1 INFO: rcu detected stall in dput 1 624d 624d 0/3 auto-obsoleted due to no activity on 2023/10/20 22:44
upstream INFO: rcu detected stall in dput fs 1 1941d 1941d 0/28 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in dput (2) kernel 2 1906d 1906d 0/28 closed as invalid on 2020/01/08 05:33

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=5cb/1/0x4000000000000000 softirq=66923/66932 fqs=319 
	(detected by 1, t=10502 jiffies, g=74813, q=43301)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 19881 Comm: syz.5.3285 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:div64_u64 include/linux/math64.h:69 [inline]
RIP: 0010:taprio_set_budget net/sched/sch_taprio.c:555 [inline]
RIP: 0010:advance_sched+0x630/0x940 net/sched/sch_taprio.c:761
Code: 00 e8 34 d2 3d f9 48 89 e8 48 c1 e8 03 42 80 3c 20 00 4c 8b 64 24 50 74 08 48 89 ef e8 89 d0 3d f9 4c 89 f0 31 d2 48 f7 75 00 <48> 89 c5 48 89 df be 04 00 00 00 e8 10 d2 3d f9 48 89 d8 48 c1 e8
RSP: 0018:ffffc90000007cc0 EFLAGS: 00000046
RAX: 000000000a000000 RBX: ffff88801f1a42a0 RCX: ffffffff888c9d4c
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8880795ccae0
RBP: ffff8880795ccae0 R08: dffffc0000000000 R09: ffffed100f2b995d
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880795cc800
R13: ffff8880795ccb40 R14: 0000000fa0000000 R15: 004bf58cc8000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560cf8520131 CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x598/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x78/0x80 kernel/kcov.c:302
Code: c1 e1 05 48 8d 41 28 4c 39 c8 77 1e 48 c7 44 11 08 07 00 00 00 48 89 7c 11 10 48 89 74 11 18 4c 89 44 11 20 49 ff c2 4c 89 12 <c3> 0f 1f 80 00 00 00 00 41 57 41 56 41 54 53 48 8b 46 08 48 83 c0
RSP: 0018:ffffc9000420f340 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffffea00013bd400 RCX: ffff88802bbd1dc0
RDX: 0000000000000000 RSI: 00fff00000080035 RDI: ffffffffffffffff
RBP: 1ffffd4000277a81 R08: ffffffff81a897ef R09: fffff94000277a87
R10: 0000000000000000 R11: dffffc0000000001 R12: 00fff00000080035
R13: dffffc0000000000 R14: ffffea00013bd400 R15: ffffea00013bd408
 PagePoisoned include/linux/page-flags.h:218 [inline]
 PageLocked include/linux/page-flags.h:342 [inline]
 unlock_page+0xbf/0x200 mm/filemap.c:1511
 shmem_undo_range+0x547/0x1b50 mm/shmem.c:961
 shmem_truncate_range mm/shmem.c:1063 [inline]
 shmem_evict_inode+0x21b/0xa00 mm/shmem.c:1145
 evict+0x529/0x930 fs/inode.c:622
 __dentry_kill+0x436/0x650 fs/dcache.c:586
 dentry_kill+0xbb/0x290
 dput+0xd8/0x1a0 fs/dcache.c:893
 __fput+0x636/0x8e0 fs/file_table.c:288
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0x6a3/0x2480 kernel/exit.c:874
 do_group_exit+0x144/0x310 kernel/exit.c:996
 get_signal+0xc66/0x14e0 kernel/signal.c:2900
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f1157572169
Code: Unable to access opcode bytes at RIP 0x7f115757213f.
RSP: 002b:00007f11553ba038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000010106 RBX: 00007f115778b080 RCX: 00007f1157572169
RDX: 0000000000010106 RSI: 00004000000000c0 RDI: 0000000000000003
RBP: 00007f11575f32a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f115778b080 R15: 00007ffda8ba5568
 </TASK>
rcu: rcu_preempt kthread starved for 8869 jiffies! g74813 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:26488 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 17628 Comm: kworker/1:3 Not tainted 5.15.178-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events perf_sched_delayed
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xa93/0xd90 kernel/smp.c:969
Code: 04 03 84 c0 0f 85 84 00 00 00 45 8b 7d 00 44 89 fe 83 e6 01 31 ff e8 3c d6 0b 00 41 83 e7 01 75 07 e8 d1 d2 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00
RSP: 0018:ffffc900033df940 EFLAGS: 00000293
RAX: ffffffff8174b2e4 RBX: 1ffff110171c8541 RCX: ffff888077878000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900033dfa80 R08: ffffffff8174b2b4 R09: fffffbfff2131821
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff8880b8e42a08 R14: ffff8880b8f3b380 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1207 [inline]
 text_poke_bp_batch+0x2b4/0x930 arch/x86/kernel/alternative.c:1407
 text_poke_flush arch/x86/kernel/alternative.c:1598 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1605
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_disable_cpuslocked+0xca/0x1b0 kernel/jump_label.c:207
 static_key_disable+0x16/0x20 kernel/jump_label.c:215
 perf_sched_delayed+0x61/0x80 kernel/events/core.c:5012
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/12 05:52 linux-5.15.y c16c81c81336 ee70e6db .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in dput
2025/03/04 13:02 linux-5.15.y c16c81c81336 c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in dput
2025/01/03 21:59 linux-5.15.y 91786f140358 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in dput
2025/01/01 15:22 linux-5.15.y 91786f140358 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in dput
2024/12/12 19:52 linux-5.15.y 0a51d2d4527b 530e80f8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in dput
2024/12/09 17:02 linux-5.15.y 0a51d2d4527b 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in dput
* Struck through repros no longer work on HEAD.