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INFO: rcu detected stall in mntput (2)

Status: auto-obsoleted due to no activity on 2024/11/25 12:43
Subsystems: fs
[Documentation on labels]
First crash: 458d, last: 458d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in mntput fs 1 1 934d 934d 0/29 auto-obsoleted due to no activity on 2023/08/06 23:33
upstream INFO: rcu detected stall in mntput (3) fs 1 1 188d 188d 0/29 auto-obsoleted due to no activity on 2025/08/22 03:54
android-6-1 BUG: soft lockup in mntput 1 1 445d 445d 0/2 auto-obsoleted due to no activity on 2024/12/08 11:00
android-5-10 BUG: soft lockup in mntput 1 1 382d 382d 0/2 auto-obsoleted due to no activity on 2025/02/08 13:50
android-6-12 BUG: soft lockup in mntput 1 2 40d 52d 0/1 premoderation: reported on 2025/10/06 14:39

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4670/1:b..l P5301/1:b..l P5218/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=11865, q=741 ncpus=2)
task:syz-executor    state:R  running task     stack:23280 pid:5218  tgid:5218  ppid:5212   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6708
 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:1191 [inline]
 copy_pmd_range mm/memory.c:1252 [inline]
 copy_pud_range mm/memory.c:1289 [inline]
 copy_p4d_range mm/memory.c:1313 [inline]
 copy_page_range+0x1c95/0x57d0 mm/memory.c:1411
 dup_mmap kernel/fork.c:749 [inline]
 dup_mm kernel/fork.c:1672 [inline]
 copy_mm kernel/fork.c:1721 [inline]
 copy_process+0x8117/0x8de0 kernel/fork.c:2374
 kernel_clone+0xfd/0x960 kernel/fork.c:2781
 __do_sys_clone+0xba/0x100 kernel/fork.c:2924
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe4aeb706d3
RSP: 002b:00007ffdd22ed378 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe4aeb706d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 000055558438e7d0 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000001ec01 R14: 000000000001eb4f R15: 00007ffdd22ed500
 </TASK>
task:udevd           state:R  running task     stack:26480 pid:5301  tgid:5301  ppid:4670   flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5727
Code: c1 05 ea 13 9a 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc900036afcb0 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff920006d5f98 RCX: 0000000000000001
RDX: 0000000000000001 RSI: ffffffff8b4cc800 RDI: ffffffff8bb09b80
RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff28c5ae0
R10: ffffffff9462d707 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8ddb5d20 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 rcu_read_lock include/linux/rcupdate.h:838 [inline]
 mntput_no_expire+0xa1/0xaf0 fs/namespace.c:1399
 mntput+0x6b/0x90 fs/namespace.c:1469
 __fput+0x57b/0xbb0 fs/file_table.c:433
 __fput_sync+0x47/0x50 fs/file_table.c:507
 __do_sys_close fs/open.c:1566 [inline]
 __se_sys_close fs/open.c:1551 [inline]
 __x64_sys_close+0x86/0x100 fs/open.c:1551
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2d2a3170a8
RSP: 002b:00007ffdf314e7c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00005636aa279c80 RCX: 00007f2d2a3170a8
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 00005636aa279c80 R08: 0000000000000007 R09: dbe8dc0b6ad975dd
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
 </TASK>
task:udevd           state:R  running task     stack:26448 pid:4670  tgid:4670  ppid:1      flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6708
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:194
 sock_def_readable+0x160/0x610 net/core/sock.c:3374
 __netlink_sendskb net/netlink/af_netlink.c:1278 [inline]
 netlink_sendskb net/netlink/af_netlink.c:1284 [inline]
 netlink_unicast+0x6f1/0x7f0 net/netlink/af_netlink.c:1372
 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0xab5/0xc90 net/socket.c:2597
 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2651
 __sys_sendmsg+0x117/0x1f0 net/socket.c:2680
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2d2a324a4b
RSP: 002b:00007ffdf3153d48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00005636aa231240 RCX: 00007f2d2a324a4b
RDX: 0000000000000000 RSI: 00007ffdf3153d58 RDI: 0000000000000004
RBP: 00005636aa259a00 R08: 0000000000000001 R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000000b2 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10563 jiffies! g11865 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:27584 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6621
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2236
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 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+0x1a/0x20 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
2024/08/27 12:42 upstream 3e9bff3bbe13 9aee4e0b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in mntput
* Struck through repros no longer work on HEAD.