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INFO: rcu detected stall in sys_creat (6)

Status: auto-obsoleted due to no activity on 2025/05/04 14:13
Subsystems: cgroups mm
[Documentation on labels]
First crash: 139d, last: 139d
▶ ▼ Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_creat exfat 98 2345d 2436d 0/29 closed as dup on 2019/01/20 01:52
upstream INFO: rcu detected stall in sys_creat (5) cgroups mm fs 2 364d 410d 0/29 auto-obsoleted due to no activity on 2024/08/22 00:53
upstream INFO: rcu detected stall in sys_creat (4) mm cgroups 1 1357d 1357d 0/29 auto-closed as invalid on 2021/12/03 06:38
upstream INFO: rcu detected stall in sys_creat (2) kernel 1 2028d 2028d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in sys_creat (3) fs 1 1799d 1799d 0/29 auto-closed as invalid on 2020/10/17 06:02
linux-6.1 INFO: rcu detected stall in sys_creat 1 670d 670d 0/3 auto-obsoleted due to no activity on 2023/11/30 18:44
linux-5.15 INFO: rcu detected stall in sys_creat 1 273d 273d 0/3 auto-obsoleted due to no activity on 2024/12/31 15:05
android-5-15 BUG: soft lockup in sys_creat 4 391d 422d 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: 	1-...!: (0 ticks this GP) idle=38e4/1/0x4000000000000000 softirq=71764/71764 fqs=0
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P11499/1:b..l
rcu: 	(detected by 0, t=10506 jiffies, g=65049, q=110 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 18254 Comm: syz.4.3142 Not tainted 6.14.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:122 [inline]
RIP: 0010:lock_acquire+0x144/0x550 kernel/locking/lockdep.c:5827
Code: 8b 05 70 d1 67 7e 85 c0 0f 85 8f 01 00 00 65 48 8b 1c 25 c0 d4 03 00 48 81 c3 ec 0a 00 00 48 89 d8 48 c1 e8 03 42 0f b6 04 28 <84> c0 0f 85 e5 02 00 00 83 3b 00 0f 85 62 01 00 00 4c 8d bc 24 80
RSP: 0018:ffffc90000a18b00 EFLAGS: 00000807
RAX: 0000000000000000 RBX: ffff88802b2846ec RCX: ffffffff819ab8c4
RDX: 0000000000000000 RSI: ffffffff8c5fb5a0 RDI: ffffffff8c5fb560
RBP: ffffc90000a18c48 R08: ffffffff901a2777 R09: 1ffffffff20344ee
R10: dffffc0000000000 R11: fffffbfff20344ef R12: 1ffff92000143168
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff88802b2846d8
FS:  00007fddbd9a46c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c325c64 CR3: 0000000035766000 CR4: 00000000003526f0
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0xab/0xca0 net/sched/sch_taprio.c:924
 __run_hrtimer kernel/time/hrtimer.c:1738 [inline]
 __hrtimer_run_queues+0x59b/0xd30 kernel/time/hrtimer.c:1802
 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1864
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:try_charge_memcg+0x4e0/0x1150 mm/memcontrol.c:2216
Code: 44 24 18 00 02 00 00 75 1b 80 7c 24 38 00 75 20 e9 90 09 00 00 e8 90 8a c2 09 f7 44 24 18 00 02 00 00 74 e5 fb 80 7c 24 38 00 <0f> 84 75 09 00 00 e9 06 02 00 00 44 89 fb 48 8b bc 24 80 00 00 00
RSP: 0018:ffffc9000d7cf480 EFLAGS: 00000246
RAX: 631577697e2b6b00 RBX: 1ffff92001af9eaa RCX: ffffffff9a3ca903
RDX: dffffc0000000000 RSI: ffffffff8c0aa660 RDI: ffffc9000d7cf550
RBP: ffffc9000d7cf630 R08: ffffffff901a2777 R09: 1ffffffff20344ee
R10: dffffc0000000000 R11: fffffbfff20344ef R12: ffff88807eace000
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000040
 obj_cgroup_charge_pages+0x91/0x230 mm/memcontrol.c:2636
 obj_cgroup_charge+0x380/0x5d0 mm/memcontrol.c:2927
 __memcg_slab_post_alloc_hook+0x1b1/0x7e0 mm/memcontrol.c:2988
 memcg_slab_post_alloc_hook mm/slub.c:2152 [inline]
 slab_post_alloc_hook mm/slub.c:4125 [inline]
 slab_alloc_node mm/slub.c:4164 [inline]
 kmem_cache_alloc_noprof+0x287/0x380 mm/slub.c:4171
 alloc_empty_file+0x9e/0x1d0 fs/file_table.c:228
 path_openat+0x107/0x3590 fs/namei.c:3975
 do_filp_open+0x27f/0x4e0 fs/namei.c:4016
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1427
 do_sys_open fs/open.c:1442 [inline]
 __do_sys_creat fs/open.c:1520 [inline]
 __se_sys_creat fs/open.c:1514 [inline]
 __x64_sys_creat+0x123/0x170 fs/open.c:1514
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fddbcb8cda9
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:00007fddbd9a4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fddbcda5fa0 RCX: 00007fddbcb8cda9
RDX: 0000000000000000 RSI: 000000000000015d RDI: 0000000020000300
RBP: 00007fddbcc0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fddbcda5fa0 R15: 00007ffe5b1f1c48
 </TASK>
task:syz-executor    state:R  running task     stack:19632 pid:11499 tgid:11499 ppid:11485  task_flags:0x400140 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5377 [inline]
 __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6943
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6967
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 copy_pte_range mm/memory.c:1201 [inline]
 copy_pmd_range+0x6dc8/0x77a0 mm/memory.c:1262
 copy_pud_range mm/memory.c:1299 [inline]
 copy_p4d_range mm/memory.c:1323 [inline]
 copy_page_range+0x99f/0xe90 mm/memory.c:1421
 dup_mmap kernel/fork.c:748 [inline]
 dup_mm kernel/fork.c:1700 [inline]
 copy_mm+0x1269/0x2160 kernel/fork.c:1752
 copy_process+0x1845/0x3d50 kernel/fork.c:2403
 kernel_clone+0x223/0x870 kernel/fork.c:2815
 __do_sys_clone kernel/fork.c:2958 [inline]
 __se_sys_clone kernel/fork.c:2942 [inline]
 __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2942
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd4cdf83613
RSP: 002b:00007ffcb6036e88 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd4cdf83613
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555650a77d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000011b4d3 R15: 00007ffcb6037020
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g65049 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=96429
rcu: rcu_preempt kthread starved for 10506 jiffies! g65049 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25752 pid:17    tgid:17    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5377 [inline]
 __schedule+0x18bc/0x4c40 kernel/sched/core.c:6764
 __schedule_loop kernel/sched/core.c:6841 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6856
 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/03 14:06 upstream 2014c95afece a21a8419 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in sys_creat
* Struck through repros no longer work on HEAD.