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INFO: rcu detected stall in sys_mbind (5)

Status: auto-obsoleted due to no activity on 2025/06/07 08:47
Subsystems: bpf
[Documentation on labels]
First crash: 215d, last: 215d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_mbind mm 1 4 2359d 2390d 0/29 auto-closed as invalid on 2019/10/22 22:44
upstream INFO: rcu detected stall in sys_mbind (2) mm 1 1 1886d 1886d 0/29 auto-closed as invalid on 2020/11/09 09:33
upstream INFO: rcu detected stall in sys_mbind (4) mm 1 1 412d 412d 0/29 auto-obsoleted due to no activity on 2024/11/22 04:15
upstream INFO: rcu detected stall in sys_mbind (3) cgroups mm 1 1 484d 484d 0/29 auto-obsoleted due to no activity on 2024/08/12 04:57
linux-4.19 BUG: soft lockup in sys_mbind 1 syz error 1 1619d 1619d 0/1 upstream: reported syz repro on 2021/05/05 05:15

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P20579/3:b..l P20577/3:b..l P20583/3:b..l P20530/1:b..l P20568/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=116389, q=671 ncpus=2)
task:syz.2.2976      state:R  running task     stack:26040 pid:20568 tgid:20566 ppid:17357  task_flags:0x40054c flags:0x20004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0x190e/0x4c90 kernel/sched/core.c:6765
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6944
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6968
 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]
 zap_pte_range mm/memory.c:1772 [inline]
 zap_pmd_range mm/memory.c:1834 [inline]
 zap_pud_range mm/memory.c:1863 [inline]
 zap_p4d_range mm/memory.c:1884 [inline]
 unmap_page_range+0x3a0d/0x4510 mm/memory.c:1905
 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1995
 exit_mmap+0x283/0xd40 mm/mmap.c:1284
 __mmput+0x115/0x420 kernel/fork.c:1356
 exit_mm+0x220/0x310 kernel/exit.c:570
 do_exit+0x9ad/0x28e0 kernel/exit.c:925
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 get_signal+0x168c/0x1720 kernel/signal.c:3036
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
 __do_fast_syscall_32+0xc4/0x110 arch/x86/entry/common.c:390
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:412
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7fb0579
RSP: 002b:00000000f50d655c EFLAGS: 00000206 ORIG_RAX: 00000000000000f6
RAX: 0000000000000000 RBX: 00000000f7fab000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:syz.5.2972      state:R  running task     stack:22008 pid:20530 tgid:20515 ppid:18902  task_flags:0x400040 flags:0x20004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0x190e/0x4c90 kernel/sched/core.c:6765
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7087
 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:5876
Code: 3c 3b 00 74 08 4c 89 f7 e8 15 1b 8c 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:ffffc90004906ba0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92000920d86 RCX: ffffc90004906c03
RDX: 0000000000000000 RSI: ffffffff8c2ac500 RDI: ffffffff8c80ff20
RBP: ffffc90004906cd8 R08: ffffffff903cf777 R09: 1ffffffff2079eee
R10: dffffc0000000000 R11: fffffbfff2079eef R12: 1ffff92000920d80
R13: 0000000000000246 R14: ffffc90004906c30 R15: dffffc0000000000
 rcu_lock_release include/linux/rcupdate.h:347 [inline]
 rcu_read_unlock include/linux/rcupdate.h:880 [inline]
 is_bpf_text_address+0x280/0x2a0 kernel/bpf/core.c:774
 kernel_text_address+0xa7/0xe0 kernel/extable.c:125
 __kernel_text_address+0xd/0x40 kernel/extable.c:79
 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0xfd/0x150 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 save_stack+0xfb/0x1f0 mm/page_owner.c:156
 __set_page_owner+0x89/0x530 mm/page_owner.c:320
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1551
 prep_new_page mm/page_alloc.c:1559 [inline]
 get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3477
 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4739
 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2270
 folio_alloc_mpol_noprof mm/mempolicy.c:2289 [inline]
 alloc_migration_target_by_mpol+0x33c/0x5d0 mm/mempolicy.c:1243
 migrate_folio_unmap mm/migrate.c:1207 [inline]
 migrate_pages_batch+0x8e6/0x30b0 mm/migrate.c:1866
 migrate_pages_sync mm/migrate.c:1989 [inline]
 migrate_pages+0x2007/0x3680 mm/migrate.c:2098
 do_mbind mm/mempolicy.c:1394 [inline]
 kernel_mbind mm/mempolicy.c:1537 [inline]
 __do_sys_mbind mm/mempolicy.c:1611 [inline]
 __se_sys_mbind+0x1489/0x1950 mm/mempolicy.c:1607
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb4/0x110 arch/x86/entry/common.c:387
 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:412
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf746d579
RSP: 002b:00000000f50d555c EFLAGS: 00000206 ORIG_RAX: 0000000000000112
RAX: ffffffffffffffda RBX: 0000000080001000 RCX: 0000000000800000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:modprobe        state:R  running task     stack:24696 pid:20583 tgid:20583 ppid:13     task_flags:0x400000 flags:0x00000000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0x190e/0x4c90 kernel/sched/core.c:6765
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6944
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6968
 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]
 filemap_map_pages+0x13ce/0x1900 mm/filemap.c:3822
 do_fault_around mm/memory.c:5361 [inline]
 do_read_fault mm/memory.c:5394 [inline]
 do_fault mm/memory.c:5537 [inline]
 do_pte_missing mm/memory.c:4058 [inline]
 handle_pte_fault mm/memory.c:5900 [inline]
 __handle_mm_fault+0x4acb/0x70f0 mm/memory.c:6043
 handle_mm_fault+0x3e5/0x8d0 mm/memory.c:6212
 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline]
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x459/0x8b0 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f88517594a1
RSP: 002b:00007ffe929b6898 EFLAGS: 00010206
RAX: 0000022314377512 RBX: 00007f885177aab0 RCX: 00007f885174b510
RDX: 0000022300000000 RSI: 00007f8851779e60 RDI: 00007f885177aab0
RBP: 00007ffe929b6950 R08: 0000000000000007 R09: 0000002300000007
R10: 00007f885175cc40 R11: 000000006fff000a R12: 00007ffe929b6960
R13: 00007ffe929b68e0 R14: 00007ffe929b6920 R15: 00007f885174b858
 </TASK>
task:sed             state:R  running task     stack:22848 pid:20577 tgid:20577 ppid:20576  task_flags:0x400000 flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0x190e/0x4c90 kernel/sched/core.c:6765
 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6944
 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6968
 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]
 filemap_map_pages+0x13ce/0x1900 mm/filemap.c:3822
 do_fault_around mm/memory.c:5361 [inline]
 do_read_fault mm/memory.c:5394 [inline]
 do_fault mm/memory.c:5537 [inline]
 do_pte_missing mm/memory.c:4058 [inline]
 handle_pte_fault mm/memory.c:5900 [inline]
 __handle_mm_fault+0x4acb/0x70f0 mm/memory.c:6043
 handle_mm_fault+0x3e5/0x8d0 mm/memory.c:6212
 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline]
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x459/0x8b0 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f4f7b692dd0
RSP: 002b:00007ffd163d9b98 EFLAGS: 00010202
RAX: 00007f4f7b7241a0 RBX: 00007ffd163d9c48 RCX: 00007ffd163d9c70
RDX: 00007ffd163d9c70 RSI: 000000000000002f RDI: 00007ffd163dade9
RBP: 00007ffd163dade9 R08: 0000000000000000 R09: 000000000000000d
R10: 00007ffd163d9880 R11: 0000000000000246 R12: 0000000000000004
R13: 00007ffd163d9c48 R14: 00007ffd163d9c70 R15: 0000000000000000
 </TASK>
task:modprobe        state:R  running task     stack:22240 pid:20579 tgid:20579 ppid:12     task_flags:0x400000 flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0x190e/0x4c90 kernel/sched/core.c:6765
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7087
 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_acquire+0x264/0x550 kernel/locking/lockdep.c:5855
Code: 2b 00 74 08 4c 89 f7 e8 ca 46 8c 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0000:ffffc900042cf5e0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92000859ec8 RCX: ffff88802a0164e8
RDX: dffffc0000000000 RSI: ffffffff8c2ac500 RDI: ffffffff8c80ff20
RBP: ffffc900042cf728 R08: ffffffff9454a847 R09: 1ffffffff28a9508
R10: dffffc0000000000 R11: fffffbfff28a9509 R12: 1ffff92000859ec4
R13: dffffc0000000000 R14: ffffc900042cf640 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 rcu_read_lock include/linux/rcupdate.h:849 [inline]
 page_ref_add_unless include/linux/page_ref.h:235 [inline]
 folio_ref_add_unless include/linux/page_ref.h:248 [inline]
 folio_try_get+0x3b/0x350 include/linux/page_ref.h:264
 next_uptodate_folio+0xd3/0x5f0 mm/filemap.c:3637
 filemap_map_pages+0x2ea/0x1900 mm/filemap.c:3779
 do_fault_around mm/memory.c:5361 [inline]
 do_read_fault mm/memory.c:5394 [inline]
 do_fault mm/memory.c:5537 [inline]
 do_pte_missing mm/memory.c:4058 [inline]
 handle_pte_fault mm/memory.c:5900 [inline]
 __handle_mm_fault+0x4acb/0x70f0 mm/memory.c:6043
 handle_mm_fault+0x3e5/0x8d0 mm/memory.c:6212
 do_user_addr_fault arch/x86/mm/fault.c:1337 [inline]
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x459/0x8b0 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x55a697dee070
RSP: 002b:00007ffc4a5f2db0 EFLAGS: 00010206
RAX: 0000000041f1d21c RBX: 0000000000000000 RCX: 00007ffc4a5f2de0
RDX: 00007f2741ef1b5d RSI: 00007f2741f1d848 RDI: 00007f2741f1d2a0
RBP: 0000000000000000 R08: 0000000000000000 R09: 38ea632e4122fa1a
R10: 000000000000004f R11: 0000000000000246 R12: 000055a697dee070
R13: 00007ffc4a5f2db0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10001 jiffies! g116389 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:25784 pid:18    tgid:18    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5378 [inline]
 __schedule+0x190e/0x4c90 kernel/sched/core.c:6765
 __schedule_loop kernel/sched/core.c:6842 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6857
 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>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.14.0-rc5-syzkaller-00234-gb7c90e3e717a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline]
RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112
Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 80 d6 03 00 48 f7 00 08 00 00 00 75 10 66 90 0f 00 2d 05 a1 81 00 f3 0f 1e fa fb f4 <fa> c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffffff8e807ca8 EFLAGS: 00000246
RAX: ffffffff8e896580 RBX: ffff888020ebe864 RCX: 000000000070a151
RDX: 0000000000000001 RSI: ffff888020ebe800 RDI: ffff888020ebe864
RBP: 000000000003aab8 R08: ffff8880b863799b R09: 1ffff110170c6f33
R10: dffffc0000000000 R11: ffffffff8c08f010 R12: ffff88801d387000
R13: 0000000000000001 R14: 0000000000000001 R15: ffffffff8f3383e0
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f504f9fe CR3: 00000000303f0000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:699
 cpuidle_enter_state+0x109/0x470 drivers/cpuidle/cpuidle.c:268
 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:389
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:230 [inline]
 do_idle+0x372/0x5c0 kernel/sched/idle.c:325
 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:423
 rest_init+0x2dc/0x300 init/main.c:743
 start_kernel+0x484/0x510 init/main.c:1099
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:515
 x86_64_start_kernel+0x66/0x70 arch/x86/kernel/head64.c:496
 common_startup_64+0x13e/0x147
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/09 08:39 upstream b7c90e3e717a 163f510d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 INFO: rcu detected stall in sys_mbind
* Struck through repros no longer work on HEAD.