rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P2/1:b..l P5830/1:b..l P5586/1:b..l rcu: (detected by 1, t=10503 jiffies, g=52881, q=524 ncpus=2) task:crond state:R running task stack:25512 pid:5586 tgid:5586 ppid:1 task_flags:0x400000 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872 Code: 77 3e 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 62 6d 13 0f 0f 82 74 02 00 00 8b 35 2a 9f 13 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 b9 76 3e 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc9000359f848 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e5c11e0 RCX: 000000006481f9f7 RDX: 0000000000000000 RSI: ffffffff8de29da0 RDI: ffffffff8c162580 RBP: 0000000000000002 R08: 9e0ff3f8210f2cbc R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 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] is_module_text_address+0x33/0x220 kernel/module/main.c:3845 kernel_text_address kernel/extable.c:119 [inline] kernel_text_address+0x81/0x100 kernel/extable.c:94 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x59/0xa0 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xa6/0x100 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x160/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x84/0x1a0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x165/0x1c0 mm/slub.c:3218 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4236 getname_flags.part.0+0x4c/0x550 fs/namei.c:146 getname_flags+0x93/0xf0 include/linux/audit.h:322 getname include/linux/fs.h:2918 [inline] do_sys_openat2+0xb8/0x1d0 fs/open.c:1429 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1461 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f860b7ebc3a RSP: 002b:00007ffc27897a18 EFLAGS: 00000206 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000561af814d300 RCX: 00007f860b7ebc3a RDX: 0000000000080000 RSI: 00007f860b88845a RDI: 00000000ffffff9c RBP: 0000000000000008 R08: 0000000000000008 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000206 R12: 00007f860b8867f4 R13: 00007f860b8867f4 R14: 0000000000000001 R15: 0000000000000033 task:syz-executor state:R running task stack:22184 pid:5830 tgid:5830 ppid:5829 task_flags:0x400100 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline] RIP: 0010:write_comp_data+0x3c/0x90 kernel/kcov.c:246 Code: 8b 05 58 b3 1a 12 a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 0f 00 75 60 a9 00 00 f0 00 75 59 8b 82 3c 16 00 00 85 c0 74 4f <8b> 82 18 16 00 00 83 f8 03 75 44 48 8b 82 20 16 00 00 8b 92 1c 16 RSP: 0018:ffffc9000377faf0 EFLAGS: 00000246 RAX: 0000000080000000 RBX: 0000000000000001 RCX: ffffffff822dc021 RDX: ffff888077dc4880 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88801f55a4a0 R13: ffff88801f55a49c R14: 0000000000000000 R15: dffffc0000000000 rcu_read_unlock include/linux/rcupdate.h:869 [inline] __page_table_check_zero+0x321/0x5d0 mm/page_table_check.c:145 page_table_check_free include/linux/page_table_check.h:43 [inline] free_pages_prepare mm/page_alloc.c:1396 [inline] __free_frozen_pages+0x7b7/0x10f0 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x165/0x1c0 mm/slub.c:3218 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4236 lsm_file_alloc security/security.c:733 [inline] security_file_alloc+0x34/0x2b0 security/security.c:2888 init_file+0x93/0x4c0 fs/file_table.c:159 alloc_empty_file+0x73/0x1e0 fs/file_table.c:241 alloc_file fs/file_table.c:354 [inline] alloc_file_clone+0x5f/0x110 fs/file_table.c:432 create_pipe_files+0x412/0x9a0 fs/pipe.c:954 __do_pipe_flags fs/pipe.c:988 [inline] do_pipe2+0xaf/0x1c0 fs/pipe.c:1036 __do_sys_pipe2 fs/pipe.c:1054 [inline] __se_sys_pipe2 fs/pipe.c:1052 [inline] __x64_sys_pipe2+0x54/0x80 fs/pipe.c:1052 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb65f38d909 RSP: 002b:00007ffc1f77d538 EFLAGS: 00000246 ORIG_RAX: 0000000000000125 RAX: ffffffffffffffda RBX: 000055557fc2cb20 RCX: 00007fb65f38d909 RDX: 0000000000000005 RSI: 0000000000000000 RDI: 00007ffc1f77d548 RBP: 00007ffc1f77d900 R08: 0000000000000007 R09: 000055557fc2bf40 R10: 30fba8b0b7a2a731 R11: 0000000000000246 R12: 00007ffc1f77d960 R13: 000055557fc311c0 R14: 00007ffc1f77d680 R15: 000055557fc34798 task:kthreadd state:R running task stack:26600 pid:2 tgid:2 ppid:0 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:239 [inline] RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline] RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:646 [inline] RIP: 0010:cpu_online include/linux/cpumask.h:1205 [inline] RIP: 0010:trace_lock_release include/trace/events/lock.h:69 [inline] RIP: 0010:lock_release+0x3b/0x2f0 kernel/locking/lockdep.c:5879 Code: 89 fb 48 83 ec 18 65 48 8b 05 b9 7d 3e 12 48 89 44 24 10 31 c0 0f 1f 44 00 00 65 8b 05 d2 7d 3e 12 83 f8 07 0f 87 38 02 00 00 <89> c0 48 0f a3 05 1b 74 13 0f 0f 82 b1 01 00 00 8b 3d e3 a5 13 0f RSP: 0018:ffffc900000775b8 EFLAGS: 00000297 RAX: 0000000000000000 RBX: ffffffff8e5c11e0 RCX: ffffc90000078001 RDX: 0000000000000000 RSI: ffffffff816ae8a4 RDI: ffffffff8e5c11e0 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000012be5 R12: ffffffff816ae8a4 R13: ffffc90000077670 R14: ffffc900000778b0 R15: ffffc900000776a4 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x3f9/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x160/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x84/0x1a0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895 discard_slab mm/slub.c:2753 [inline] __put_partials+0x165/0x1c0 mm/slub.c:3218 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:340 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] __kmalloc_cache_noprof+0x1f1/0x3e0 mm/slub.c:4391 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] set_kthread_struct+0xcb/0x380 kernel/kthread.c:125 copy_process+0x3107/0x7690 kernel/fork.c:2102 kernel_clone+0xfc/0x930 kernel/fork.c:2605 kernel_thread+0xd4/0x120 kernel/fork.c:2667 create_kthread kernel/kthread.c:486 [inline] kthreadd+0x503/0x800 kernel/kthread.c:846 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: rcu_preempt kthread starved for 6120 jiffies! g52881 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:27784 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x5d7/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.17.0-rc1-syzkaller-00111-g24ea63ea3877 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82 Code: 8c 62 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 a2 16 00 fb f4 4c 0d 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff8e207e08 EFLAGS: 000002c2 RAX: 0000000002ca1efd RBX: 0000000000000000 RCX: ffffffff8b936c29 RDX: 0000000000000000 RSI: ffffffff8de4f295 RDI: ffffffff8c162580 RBP: fffffbfff1c52ef8 R08: 0000000000000001 R09: ffffed1017086655 R10: ffff8880b84332ab R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8e2977c0 R14: ffffffff90ab3690 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881246bc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055557541f5c8 CR3: 000000005d145000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x391/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:428 rest_init+0x16b/0x2b0 init/main.c:744 start_kernel+0x3ee/0x4d0 init/main.c:1097 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288 common_startup_64+0x13e/0x148