syzbot


INFO: rcu detected stall in dput (2)

Status: upstream: reported on 2024/03/15 21:30
Reported-by: syzbot+8070d18dbf272904961e@syzkaller.appspotmail.com
First crash: 75d, last: 5d23h
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in dput (2) 1 1d14h 1d14h 0/3 upstream: reported on 2024/05/28 13:43
upstream INFO: rcu detected stall in dput (4) kvm C error error 2 901d 1261d 0/26 closed as invalid on 2022/02/08 10:37
upstream INFO: rcu detected stall in dput (3) kernel 1 1603d 1603d 0/26 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in dput (8) mm C done 36 6h16m 150d 0/26 upstream: reported C repro on 2023/12/31 19:35
linux-5.15 INFO: rcu detected stall in dput 2 274d 314d 0/3 auto-obsoleted due to no activity on 2023/12/08 00:28
upstream INFO: rcu detected stall in dput (6) fs 2 575d 634d 0/26 auto-obsoleted due to no activity on 2023/01/16 04:13
upstream INFO: rcu detected stall in dput (5) fs 1 771d 771d 0/26 auto-closed as invalid on 2022/07/18 12:41
linux-6.1 INFO: rcu detected stall in dput 1 322d 322d 0/3 auto-obsoleted due to no activity on 2023/10/20 22:44
upstream INFO: rcu detected stall in dput fs 1 1638d 1638d 0/26 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in dput (2) kernel 2 1603d 1603d 0/26 closed as invalid on 2020/01/08 05:33

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=26f/1/0x4000000000000000 softirq=20700/20703 fqs=0 
	(detected by 0, t=10502 jiffies, g=32053, q=61)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7028 Comm: syz-executor.0 Not tainted 5.15.159-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3682 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3701 [inline]
RIP: 0010:validate_chain+0x199/0x5930 kernel/locking/lockdep.c:3756
Code: 89 df e8 6a c5 66 00 48 89 5c 24 20 48 8b 1b 48 85 db 74 48 48 83 c3 f8 74 42 4c 8d 7b 18 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 <74> 08 4c 89 ff e8 3d c5 66 00 49 8b 07 4c 39 f0 0f 84 d4 03 00 00
RSP: 0018:ffffc90000dd07c0 EFLAGS: 00000046
RAX: 1ffffffff1f9077b RBX: ffffffff8fc83bc0 RCX: ffffffff81636502
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fbf80c8
RBP: ffffc90000dd0a70 R08: dffffc0000000000 R09: fffffbfff1f7f01a
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88807e0ce450 R14: 4b21b045db16ba9e R15: ffffffff8fc83bd8
FS:  0000555555d0d480(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2016c196e4 CR3: 0000000062b95000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline]
 _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x662/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:196
Code: 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d e8 0c 64 0c 48 89 de 5b e9 f7 f6 48 00 cc cc cc cc cc cc cc 48 8b 04 24 <65> 48 8b 0d f4 12 82 7e 65 8b 15 f5 12 82 7e f7 c2 00 01 ff 00 74
RSP: 0018:ffffc900036a7878 EFLAGS: 00000246
RAX: ffffffff81a7e12e RBX: 00fff00000080017 RCX: ffff88807e0cd940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 1ffffd40002b0398 R08: ffffffff81a7e120 R09: fffff940002b0399
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: 1ffffd40002b0399 R14: ffffea0001581cc8 R15: ffffea0001581cc0
 page_cache_free_page+0x11e/0x510 mm/filemap.c:244
 truncate_inode_page+0x8d/0xb0 mm/truncate.c:219
 shmem_undo_range+0x535/0x1b50 mm/shmem.c:960
 shmem_truncate_range mm/shmem.c:1063 [inline]
 shmem_evict_inode+0x21b/0xa00 mm/shmem.c:1145
 evict+0x2a4/0x620 fs/inode.c:587
 __dentry_kill+0x436/0x650 fs/dcache.c:582
 dentry_kill+0xbb/0x290
 dput+0xd8/0x1a0 fs/dcache.c:889
 __fput+0x5ec/0x890 fs/file_table.c:288
 task_work_run+0x129/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 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: 0033:0x7f91427f4217
Code: b0 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b0 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd5f985718 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f91427f4217
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd5f9857d0
RBP: 00007ffd5f9857d0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd5f986890
R13: 00007f914283e336 R14: 000000000003ea7f R15: 0000000000000005
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g32053 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:27000 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 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:300
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 4439 Comm: kworker/0:15 Not tainted 5.15.159-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: events fqdir_free_fn
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:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_single+0x292/0x530 kernel/smp.c:758
Code: 0f 85 24 02 00 00 44 8b 6c 24 48 44 89 ee 83 e6 01 31 ff e8 90 e4 0b 00 41 83 e5 01 75 0a e8 25 e1 0b 00 e9 eb 00 00 00 f3 90 <42> 0f b6 04 23 84 c0 75 15 f7 44 24 48 01 00 00 00 0f 84 cd 00 00
RSP: 0018:ffffc90004477a60 EFLAGS: 00000293
RAX: ffffffff81747bbe RBX: 1ffff9200088ef55 RCX: ffff888074b95940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004477b50 R08: ffffffff81747b90 R09: ffffed1017367681
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffc90004477aa8 R15: 0000000000000000
 rcu_barrier+0x262/0x4e0 kernel/rcu/tree.c:4078
 fqdir_free_fn+0x2e/0x130 net/ipv4/inet_fragment.c:163
 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:300
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/24 04:22 linux-5.15.y 83655231580b 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in dput
2024/05/19 22:51 linux-5.15.y 83655231580b c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in dput
2024/03/23 20:19 linux-5.15.y b95c01af2113 0ea90952 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in dput
2024/03/15 21:29 linux-5.15.y b95c01af2113 d615901c .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.