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INFO: rcu detected stall in sys_creat

Status: upstream: reported on 2024/09/22 15:05
Reported-by: syzbot+66ec6538deb91bbcf89a@syzkaller.appspotmail.com
First crash: 74d, last: 74d
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_creat exfat 98 2146d 2237d 0/28 closed as dup on 2019/01/20 01:52
upstream INFO: rcu detected stall in sys_creat (5) cgroups mm fs 2 165d 211d 0/28 auto-obsoleted due to no activity on 2024/08/22 00:53
upstream INFO: rcu detected stall in sys_creat (4) mm cgroups 1 1158d 1158d 0/28 auto-closed as invalid on 2021/12/03 06:38
upstream INFO: rcu detected stall in sys_creat (2) kernel 1 1829d 1829d 0/28 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in sys_creat (3) fs 1 1600d 1600d 0/28 auto-closed as invalid on 2020/10/17 06:02
linux-6.1 INFO: rcu detected stall in sys_creat 1 471d 471d 0/3 auto-obsoleted due to no activity on 2023/11/30 18:44
android-5-15 BUG: soft lockup in sys_creat 4 192d 223d 0/2 auto-obsoleted due to no activity on 2024/08/25 01:26

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=3ef/1/0x4000000000000000 softirq=35146/35146 fqs=5 
	(detected by 1, t=10502 jiffies, g=49221, q=73)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9120 Comm: syz.1.1084 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:debug_spin_lock_before kernel/locking/spinlock_debug.c:86 [inline]
RIP: 0010:do_raw_spin_lock+0xce/0x370 kernel/locking/spinlock_debug.c:114
Code: 20 80 3c 10 00 74 12 4c 89 ef e8 ed 01 66 00 48 ba 00 00 00 00 00 fc ff df 49 8b 45 00 65 48 8b 0d 07 4d 9e 7e 48 89 4c 24 28 <48> 39 c8 0f 84 38 01 00 00 49 8d 5c 24 08 49 89 df 49 c1 ef 03 41
RSP: 0018:ffffc90000007be0 EFLAGS: 00000046
RAX: ffffffffffffffff RBX: ffff8880b902a204 RCX: ffff888027aa9dc0
RDX: dffffc0000000000 RSI: 1ffff92000000f84 RDI: ffff8880b902a200
RBP: ffffc90000007cb0 R08: dffffc0000000000 R09: fffffbfff20e241a
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b902a200
R13: ffff8880b902a210 R14: ffffc90000007ce0 R15: dffffc0000000000
FS:  00007f48e08166c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f48e0815f98 CR3: 000000007d085000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:129 [inline]
 _raw_spin_lock_irq+0xdb/0x110 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1692 [inline]
 __hrtimer_run_queues+0x662/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c: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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194
Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 f2 3e 8c f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 87 87 19 f7 65 8b 05 08 8a c4 75 85 c0 74 3f 48 c7 04 24 0e 36
RSP: 0018:ffffc90002dd75c0 EFLAGS: 00000206
RAX: ea0be1a68a3ee200 RBX: 1ffff920005baebc RCX: ffffffff81631ae8
RDX: dffffc0000000000 RSI: ffffffff8a8b2b00 RDI: 0000000000000001
RBP: ffffc90002dd7650 R08: dffffc0000000000 R09: fffffbfff20e241a
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 1ffff920005baeb8 R14: ffffc90002dd75e0 R15: 0000000000000246
 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up+0x120/0x1c0 kernel/sched/wait.c:157
 __d_lookup_done+0x16e/0x2a0 fs/dcache.c:2692
 __d_add+0x45b/0x7f0 fs/dcache.c:2710
 d_splice_alias+0x10f/0x330 fs/dcache.c:3107
 vfat_lookup+0x2bc/0x5d0 fs/fat/namei_vfat.c:753
 lookup_open fs/namei.c:3440 [inline]
 open_last_lookups fs/namei.c:3532 [inline]
 path_openat+0x111d/0x2f20 fs/namei.c:3739
 do_filp_open+0x21c/0x460 fs/namei.c:3769
 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_creat fs/open.c:1343 [inline]
 __se_sys_creat fs/open.c:1337 [inline]
 __x64_sys_creat+0x11f/0x160 fs/open.c:1337
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f48e23dfef9
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:00007f48e0816038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f48e2598130 RCX: 00007f48e23dfef9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040
RBP: 00007f48e2452b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f48e2598130 R15: 00007ffe61a18798
 </TASK>
rcu: rcu_preempt kthread starved for 10475 jiffies! g49221 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:26752 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: 9122 Comm: syz.4.1085 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
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: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_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 8c cc 0b 00 41 83 e7 01 75 07 e8 21 c9 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:ffffc90002e67c20 EFLAGS: 00000246
RAX: ffffffff81749174 RBX: 1ffff11017208541 RCX: 0000000000040000
RDX: ffffc90003c0b000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc90002e67d48 R08: ffffffff81749144 R09: fffffbfff20e243a
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff8880b9042a08 R14: ffff8880b913b380 R15: 0000000000000001
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1135
 on_each_cpu include/linux/smp.h:71 [inline]
 hardware_enable_all+0x77/0x120 virt/kvm/kvm_main.c:4920
 kvm_create_vm virt/kvm/kvm_main.c:1148 [inline]
 kvm_dev_ioctl_create_vm virt/kvm/kvm_main.c:4753 [inline]
 kvm_dev_ioctl+0x1210/0x2030 virt/kvm/kvm_main.c:4808
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fd9b3935ef9
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:00007fd9b1dae038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fd9b3aedf80 RCX: 00007fd9b3935ef9
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003
RBP: 00007fd9b39a8b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd9b3aedf80 R15: 00007fff8c492d98
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/22 15:05 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in sys_creat
* Struck through repros no longer work on HEAD.