syzbot

 sign-in | mailing list | source | docs
🐞 Open [1569]
≡ Subsystems
🐞 Fixed [6331]
🐞 Invalid [16139]
⬇ Missing Backports [191]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
Total Repo Heatmap Subsystems Heatmap
💬 Send us feedback

INFO: rcu detected stall in sys_statfs

Status: auto-obsoleted due to no activity on 2024/11/02 00:42
Subsystems: mm
[Documentation on labels]
First crash: 327d, last: 327d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in sys_statfs 1 57d 57d 0/3 upstream: reported on 2025/05/01 02:27
linux-6.1 INFO: rcu detected stall in sys_statfs (2) 1 77d 77d 0/3 upstream: reported on 2025/04/11 13:57
upstream INFO: rcu detected stall in sys_statfs (2) bpf 2 97d 185d 0/29 auto-obsoleted due to no activity on 2025/06/20 15:32
linux-6.1 INFO: rcu detected stall in sys_statfs 1 379d 379d 0/3 auto-obsoleted due to no activity on 2024/09/21 08:20

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5596/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=9741, q=917 ncpus=2)
task:sed             state:R  running task     stack:23680 pid:5596  tgid:5596  ppid:5591   flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_release+0x658/0xa30 kernel/locking/lockdep.c:5784
Code: 3c 3b 00 74 08 4c 89 f7 e8 35 c8 8a 00 f6 84 24 91 00 00 00 02 75 77 41 f7 c5 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 27 00 00 00 00 4b c7 44 27 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc900020bf720 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92000417ef6 RCX: ffffc900020bf703
RDX: 0000000000000001 RSI: ffffffff8c0ae6e0 RDI: ffffffff8c605cc0
RBP: ffffc900020bf850 R08: ffffffff9017adaf R09: 1ffffffff202f5b5
R10: dffffc0000000000 R11: fffffbfff202f5b6 R12: 1ffff92000417ef0
R13: 0000000000000246 R14: ffffc900020bf7b0 R15: dffffc0000000000
 rcu_lock_release include/linux/rcupdate.h:336 [inline]
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 mt_find+0x58e/0x850 lib/maple_tree.c:6951
 find_vma+0xf9/0x170 mm/mmap.c:2019
 lock_mm_and_find_vma+0x5f/0x2f0 mm/memory.c:5933
 do_user_addr_fault arch/x86/mm/fault.c:1361 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x1bf/0x8c0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:do_strncpy_from_user lib/strncpy_from_user.c:41 [inline]
RIP: 0010:strncpy_from_user+0x110/0x2e0 lib/strncpy_from_user.c:139
Code: 00 00 00 4c 89 e6 e8 cf 19 aa fc 49 83 fc 07 0f 86 9a 00 00 00 48 89 6c 24 08 48 c7 44 24 10 f8 ff ff ff 45 31 ed 4c 89 3c 24 <4f> 8b 3c 2f 48 b8 ff fe fe fe fe fe fe fe 49 8d 1c 07 4c 89 fd 48
RSP: 0018:ffffc900020bfb80 EFLAGS: 00050246
RAX: 0000000000000000 RBX: ffff88805c854400 RCX: ffff88802b4e3c00
RDX: 0000000000000000 RSI: 0000000000000fe0 RDI: 0000000000000007
RBP: 0000000000000fe0 R08: ffffffff84e96181 R09: 1ffffffff202f5b5
R10: dffffc0000000000 R11: fffffbfff202f5b6 R12: 0000000000000fe0
R13: 0000000000000000 R14: ffff88805c854420 R15: 00007fa88f89e723
 getname_flags+0xf1/0x540 fs/namei.c:150
 user_path_at+0x24/0x60 fs/namei.c:3001
 user_statfs+0xd6/0x460 fs/statfs.c:103
 __do_sys_statfs fs/statfs.c:195 [inline]
 __se_sys_statfs fs/statfs.c:192 [inline]
 __x64_sys_statfs+0xe8/0x1a0 fs/statfs.c:192
 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: 0033:0x7fa88f98168a
RSP: 002b:00007ffc80a44c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000089
RAX: ffffffffffffffda RBX: 00007fa88f8a64f8 RCX: 00007fa88f98168a
RDX: 00007fa88f8a819c RSI: 00007ffc80a44cf0 RDI: 00007fa88f89e723
RBP: 00007fa88f89e723 R08: 0000000000000000 R09: 000000000000000d
R10: 00007ffc80a44aa0 R11: 0000000000000246 R12: 00007ffc80a44cf0
R13: 00007ffc80a44e68 R14: 00007ffc80a44e90 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10264 jiffies! g9741 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:26448 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/04 00:36 upstream 17712b7ea075 1786a2a8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_statfs
* Struck through repros no longer work on HEAD.