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INFO: rcu detected stall in sys_creat (7)

Status: auto-obsoleted due to no activity on 2025/08/06 22:34
Subsystems: fs
[Documentation on labels]
First crash: 106d, last: 106d
Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_creat exfat 1 98 2407d 2498d 0/29 closed as dup on 2019/01/20 01:52
upstream INFO: rcu detected stall in sys_creat (6) cgroups mm 1 1 201d 201d 0/29 auto-obsoleted due to no activity on 2025/05/04 14:13
upstream INFO: rcu detected stall in sys_creat (5) cgroups mm fs 1 2 426d 472d 0/29 auto-obsoleted due to no activity on 2024/08/22 00:53
upstream INFO: rcu detected stall in sys_creat (4) cgroups mm 1 1 1419d 1419d 0/29 auto-closed as invalid on 2021/12/03 06:38
upstream INFO: rcu detected stall in sys_creat (2) mm 1 1 2090d 2090d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in sys_creat (3) fs 1 1 1861d 1861d 0/29 auto-closed as invalid on 2020/10/17 06:02
linux-6.1 INFO: rcu detected stall in sys_creat 1 1 732d 732d 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 1 335d 335d 0/3 auto-obsoleted due to no activity on 2024/12/31 15:05
android-5-15 BUG: soft lockup in sys_creat 1 4 453d 484d 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: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P14890/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=53033, q=84 ncpus=2)
task:syz.1.2603      state:R  running task     stack:27160 pid:14890 tgid:14889 ppid:5827   task_flags:0x400140 flags:0x00000000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 kernel/sched/core.c:6767
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7090
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5870
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 4b 02 d4 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000db77818 EFLAGS: 00000206
RAX: 6230154c581e1400 RBX: 0000000000000000 RCX: 6230154c581e1400
RDX: 0000000000000001 RSI: ffffffff8d921248 RDI: ffffffff8bc0fe60
RBP: ffffffff8171a9f5 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8171a9f5 R12: 0000000000000002
R13: ffffffff8df3b860 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2380 [inline]
 slab_free mm/slub.c:4642 [inline]
 kmem_cache_free+0x192/0x3f0 mm/slub.c:4744
 do_sys_openat2+0x154/0x1c0 fs/open.c:1437
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_creat fs/open.c:1522 [inline]
 __se_sys_creat fs/open.c:1516 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1516
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4fe238e969
RSP: 002b:00007f4fe31ed038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f4fe25b5fa0 RCX: 00007f4fe238e969
RDX: 0000000000000000 RSI: 0000000000000118 RDI: 00002000000000c0
RBP: 00007f4fe2410ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4fe25b5fa0 R15: 00007ffeb4450098
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g53033 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=49143
rcu: rcu_preempt kthread starved for 10502 jiffies! g53033 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:27496 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6860
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2248
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 14893 Comm: syz.0.2604 Not tainted 6.15.0-rc5-syzkaller-00043-gd76bb1ebb558 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:advance_sched+0x524/0xc90 net/sched/sch_taprio.c:961
Code: 48 89 44 24 50 48 c1 e8 03 48 89 44 24 70 48 89 6c 24 30 bf 10 00 00 00 4c 89 fe e8 d6 6e 4f f8 49 83 ff 0f 0f 87 f5 00 00 00 <4d> 8d b5 40 ff ff ff 4c 89 f5 48 c1 ed 03 42 80 7c 25 00 00 74 08
RSP: 0000:ffffc90000a08c70 EFLAGS: 00000093
RAX: ffffffff8970656a RBX: 7fffffffffffffff RCX: ffff88807c069e00
RDX: 0000000000010000 RSI: 0000000000000001 RDI: 0000000000000010
RBP: 0000000000000001 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014117c R12: dffffc0000000000
R13: ffff88807b5940c8 R14: ffff88807b594000 R15: 0000000000000001
FS:  000055557d9fa500(0000) GS:ffff8881261fe000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c354b2d CR3: 000000001c35e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x410 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:xas_start+0x0/0x770 lib/xarray.c:183
Code: 48 83 c4 58 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <55> 41 57 41 56 41 55 41 54 53 49 89 fe 48 bd 00 00 00 00 00 fc ff
RSP: 0000:ffffc90016417890 EFLAGS: 00000293
RAX: ffffffff8b4ced54 RBX: ffffc90016417b20 RCX: ffff88807c069e00
RDX: 0000000000000000 RSI: ffffffff8f64ea00 RDI: ffffc90016417b20
RBP: 0000000000000003 R08: ffff88807c069e00 R09: 0000000000000002
R10: 0000000000000003 R11: 0000000000000000 R12: ffffc90016417b20
R13: dffffc0000000000 R14: 000000000000012f R15: 1ffff92002c82f67
 xas_load+0x2c/0x5b0 lib/xarray.c:239
 xas_find+0x157/0x990 lib/xarray.c:1406
 next_uptodate_folio+0x32/0x5d0 mm/filemap.c:3553
 filemap_map_pages+0x21f/0x1740 mm/filemap.c:3705
 do_fault_around mm/memory.c:5476 [inline]
 do_read_fault mm/memory.c:5509 [inline]
 do_fault mm/memory.c:5652 [inline]
 do_pte_missing mm/memory.c:4160 [inline]
 handle_pte_fault mm/memory.c:5997 [inline]
 __handle_mm_fault+0x34d8/0x5380 mm/memory.c:6140
 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6309
 do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1337
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x68/0x110 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f757a66ecad
Code: ff 48 83 e8 01 48 89 ee bf 01 00 00 00 48 c1 e0 0e 48 c1 ee 06 48 01 c8 48 89 e9 81 e6 ff 3f 00 00 48 c1 e9 03 83 e1 07 d3 e7 <40> 84 bc 06 20 20 00 00 0f 85 11 fd ff ff e9 c0 fd ff ff e8 7b 2b
RSP: 002b:00007ffd95a144f0 EFLAGS: 00010202
RAX: 000000110c350000 RBX: 00007f757b4e5720 RCX: 0000000000000007
RDX: 000000000000037f RSI: 0000000000002b0d RDI: 0000000000000080
RBP: ffffffff818ac37f R08: 00007f757a9b6038 R09: 00007f757a9a2000
R10: 00007f7579dff008 R11: 0000000000000003 R12: 0000000000000003
R13: 0000000000000000 R14: ffffffff818ac960 R15: 000000000000003f
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/08 22:30 upstream d76bb1ebb558 dbf35fa1 .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.