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INFO: rcu detected stall in sys_unlink

Status: auto-obsoleted due to no activity on 2022/10/29 07:23
Subsystems: kasan mm
[Documentation on labels]
First crash: 628d, last: 628d
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_unlink (2) kernel 2 452d 537d 0/26 auto-obsoleted due to no activity on 2023/04/22 20:06
upstream INFO: rcu detected stall in sys_unlink (3) ext4 C error 20 5d15h 249d 0/26 upstream: reported C repro on 2023/08/13 23:42
linux-6.1 INFO: rcu detected stall in sys_unlink 2 16d 86d 0/3 upstream: reported on 2024/01/23 10:50
linux-5.15 INFO: rcu detected stall in sys_unlink 1 37d 37d 0/3 upstream: reported on 2024/03/12 14:47
android-5-15 BUG: soft lockup in sys_unlink 1 2d09h 2d09h 0/2 premoderation: reported on 2024/04/16 22:56

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=0a7/1/0x4000000000000000 softirq=64712/64712 fqs=0 
	(detected by 0, t=10502 jiffies, g=89993, q=77 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3631 Comm: syz-executor.3 Not tainted 5.19.0-rc8-syzkaller-00155-g6a010258447d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1654 [inline]
RIP: 0010:__hrtimer_run_queues+0x461/0xe50 kernel/time/hrtimer.c:1749
Code: 8d 3c c5 90 16 bb 8d e8 dd 01 5c 00 48 0f a3 2d b5 3c 51 0c 40 0f 92 c5 31 ff 89 ee e8 f8 bd 0f 00 40 84 ed 0f 85 14 06 00 00 <e8> ea c1 0f 00 8b 6c 24 38 48 89 e8 48 c1 e0 07 49 8d 84 06 c8 00
RSP: 0018:ffffc900003f8e40 EFLAGS: 00000046
RAX: 0000000080010002 RBX: ffff88807e0bbb40 RCX: ffffffff8169e068
RDX: ffff88807cd08200 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 170735bb23c00000
R13: ffff8880b9b2a600 R14: ffff8880b9b2a500 R15: 0000000000000001
FS:  0000555556489400(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555556492848 CR3: 0000000056d9b000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194
Code: 74 24 10 e8 da 4b e3 f7 48 89 ef e8 e2 cc e3 f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 53 d5 d6 f7 65 8b 05 3c 3b 88 76 85 c0 74 0a 5b 5d c3 e8 20 b7
RSP: 0018:ffffc9000318f800 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000200 RCX: 1ffffffff20d80a6
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffffff911f75f0 R08: 0000000000000001 R09: ffffffff906819a7
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000006
R13: 0000000000000006 R14: dead000000000100 R15: dffffc0000000000
 __debug_check_no_obj_freed lib/debugobjects.c:999 [inline]
 debug_check_no_obj_freed+0x20c/0x420 lib/debugobjects.c:1020
 free_pages_prepare mm/page_alloc.c:1377 [inline]
 free_pcp_prepare+0x2f0/0xd20 mm/page_alloc.c:1421
 free_unref_page_prepare mm/page_alloc.c:3343 [inline]
 free_unref_page_list+0x16f/0xf80 mm/page_alloc.c:3475
 release_pages+0xff6/0x2290 mm/swap.c:980
 __pagevec_release+0x77/0x100 mm/swap.c:1000
 pagevec_release include/linux/pagevec.h:82 [inline]
 folio_batch_release include/linux/pagevec.h:146 [inline]
 truncate_inode_pages_range+0x319/0x1530 mm/truncate.c:373
 ext4_evict_inode+0x515/0x1970 fs/ext4/inode.c:219
 evict+0x2ed/0x6b0 fs/inode.c:664
 iput_final fs/inode.c:1744 [inline]
 iput.part.0+0x562/0x820 fs/inode.c:1770
 iput+0x58/0x70 fs/inode.c:1760
 do_unlinkat+0x41b/0x650 fs/namei.c:4267
 __do_sys_unlink fs/namei.c:4308 [inline]
 __se_sys_unlink fs/namei.c:4306 [inline]
 __x64_sys_unlink+0xc6/0x110 fs/namei.c:4306
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7ff742888b47
Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcaa07fb28 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff742888b47
RDX: 00007ffcaa07fb60 RSI: 00007ffcaa07fb60 RDI: 00007ffcaa07fbf0
RBP: 00007ffcaa07fbf0 R08: 0000000000000001 R09: 00007ffcaa07f9c0
R10: 000055555648a873 R11: 0000000000000206 R12: 00007ff7428e22a6
R13: 00007ffcaa080cb0 R14: 000055555648a810 R15: 00007ffcaa080cf0
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g89993 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:28448 pid:   16 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5146 [inline]
 __schedule+0xa00/0x4b50 kernel/sched/core.c:6458
 schedule+0xd2/0x1f0 kernel/sched/core.c:6530
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1935
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1999
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2187
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 4244 Comm: kworker/u4:10 Not tainted 5.19.0-rc8-syzkaller-00155-g6a010258447d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Workqueue: events_unbound toggle_allocation_gate
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:518
 print_other_cpu_stall kernel/rcu/tree_stall.h:623 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:769 [inline]
 rcu_pending kernel/rcu/tree.c:3977 [inline]
 rcu_sched_clock_irq+0x2311/0x2370 kernel/rcu/tree.c:2675
 update_process_times+0x11a/0x1a0 kernel/time/timer.c:1839
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:243
 tick_sched_timer+0xee/0x120 kernel/time/tick-sched.c:1480
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:166 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200
Code: 48 89 ef 5d e9 b1 bd 4b 00 5d be 03 00 00 00 e9 e6 83 82 02 66 0f 1f 44 00 00 48 8b be a8 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 <65> 8b 05 59 d3 88 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b
RSP: 0018:ffffc900046b7948 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff8880b9b3f740 RCX: ffffffff816f001d
RDX: ffff888067dc2240 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffed1017367ee9
R13: 0000000000000001 R14: 0000000000000001 R15: dffffc0000000000
 rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline]
 cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline]
 csd_lock_wait kernel/smp.c:414 [inline]
 smp_call_function_many_cond+0x497/0x1110 kernel/smp.c:988
 on_each_cpu_cond_mask+0x56/0xa0 kernel/smp.c:1154
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1302 [inline]
 text_poke_bp_batch+0x233/0x6c0 arch/x86/kernel/alternative.c:1490
 text_poke_flush arch/x86/kernel/alternative.c:1660 [inline]
 text_poke_flush arch/x86/kernel/alternative.c:1657 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1667
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 jump_label_update+0x32f/0x410 kernel/jump_label.c:830
 static_key_enable_cpuslocked+0x1b1/0x260 kernel/jump_label.c:177
 static_key_enable+0x16/0x20 kernel/jump_label.c:190
 toggle_allocation_gate mm/kfence/core.c:811 [inline]
 toggle_allocation_gate+0x100/0x390 mm/kfence/core.c:803
 process_one_work+0x996/0x1610 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e9/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/07/31 07:22 upstream 6a010258447d fef302b1 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sys_unlink
* Struck through repros no longer work on HEAD.