rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4987/1:b..l P15211/1:b..l rcu: (detected by 1, t=10505 jiffies, g=115953, q=278 ncpus=2) task:syz-executor state:R running task stack:23944 pid:15211 tgid:15211 ppid:15208 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x205/0x970 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872 Code: 05 3b 45 25 12 83 f8 07 0f 87 d9 02 00 00 48 0f a3 05 46 84 f2 0e 0f 82 a4 02 00 00 8b 35 ce b7 f2 0e 85 f6 0f 85 bf 00 00 00 <48> 8b 44 24 30 65 48 2b 05 dd 44 25 12 0f 85 ed 02 00 00 48 83 c4 RSP: 0018:ffffc9001c7a6d58 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8dee9f9e RDI: ffffffff8c1c4480 RBP: ffffffff8e7e5560 R08: 0000000086db7919 R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] class_rcu_constructor include/linux/rcupdate.h:1181 [inline] unwind_next_frame+0xd1/0x2090 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x162/0x1e0 mm/page_owner.c:165 __set_page_owner+0x8c/0x540 mm/page_owner.c:341 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1853 prep_new_page mm/page_alloc.c:1861 [inline] get_page_from_freelist+0x11a6/0x3410 mm/page_alloc.c:3941 __alloc_frozen_pages_noprof+0x27c/0x2bc0 mm/page_alloc.c:5221 __alloc_pages_noprof mm/page_alloc.c:5255 [inline] alloc_pages_bulk_noprof+0x649/0x1360 mm/page_alloc.c:5175 ___alloc_pages_bulk mm/kasan/shadow.c:345 [inline] __kasan_populate_vmalloc_do mm/kasan/shadow.c:370 [inline] __kasan_populate_vmalloc+0xf0/0x210 mm/kasan/shadow.c:424 kasan_populate_vmalloc include/linux/kasan.h:580 [inline] alloc_vmap_area+0x95d/0x2b70 mm/vmalloc.c:2123 __get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3226 __vmalloc_node_range_noprof+0x228/0x1630 mm/vmalloc.c:4024 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4124 xt_counters_alloc+0x4c/0x70 net/netfilter/x_tables.c:1474 __do_replace+0x97/0x990 net/ipv4/netfilter/arp_tables.c:906 do_replace net/ipv6/netfilter/ip6_tables.c:1158 [inline] do_ip6t_set_ctl+0x91e/0xba0 net/ipv6/netfilter/ip6_tables.c:1644 nf_setsockopt+0x8d/0xf0 net/netfilter/nf_sockopt.c:101 ipv6_setsockopt+0x135/0x170 net/ipv6/ipv6_sockglue.c:970 tcp_setsockopt+0xa7/0x100 net/ipv4/tcp.c:4182 do_sock_setsockopt+0xf3/0x1d0 net/socket.c:2381 __sys_setsockopt+0x195/0x220 net/socket.c:2406 __do_sys_setsockopt net/socket.c:2412 [inline] __se_sys_setsockopt net/socket.c:2409 [inline] __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2409 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f420d79e69a RSP: 002b:00007ffc6f804408 EFLAGS: 00000206 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007ffc6f804490 RCX: 00007f420d79e69a RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00000000000003b8 R09: 0000000000000000 R10: 00007f420d9e8e60 R11: 0000000000000206 R12: 00007f420d9e8e00 R13: 00007ffc6f80442c R14: 0000000000000000 R15: 00007f420d9eafc0 task:udevd state:R running task stack:24136 pid:4987 tgid:4987 ppid:1 task_flags:0x400140 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline] irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x205/0x970 kernel/entry/common.c:164 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872 Code: 05 3b 45 25 12 83 f8 07 0f 87 d9 02 00 00 48 0f a3 05 46 84 f2 0e 0f 82 a4 02 00 00 8b 35 ce b7 f2 0e 85 f6 0f 85 bf 00 00 00 <48> 8b 44 24 30 65 48 2b 05 dd 44 25 12 0f 85 ed 02 00 00 48 83 c4 RSP: 0018:ffffc9000336f060 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8dee9f9e RDI: ffffffff8c1c4480 RBP: ffffffff8e7e5560 R08: 0000000086db7919 R09: 0000000000000007 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:300 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] class_rcu_constructor include/linux/rcupdate.h:1181 [inline] unwind_next_frame+0xd1/0x2090 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:556 __call_rcu_common.constprop.0+0xa5/0x9b0 kernel/rcu/tree.c:3131 security_inode_free+0xa4/0x170 security/security.c:1253 __destroy_inode+0x1ea/0x710 fs/inode.c:369 destroy_inode+0x91/0x1c0 fs/inode.c:392 evict+0x599/0xad0 fs/inode.c:865 iput_final fs/inode.c:1960 [inline] iput.part.0+0x605/0xf50 fs/inode.c:2009 iput+0x35/0x40 fs/inode.c:1975 dentry_unlink_inode+0x2c0/0x4c0 fs/dcache.c:476 __dentry_kill+0x1d0/0x690 fs/dcache.c:718 shrink_kill fs/dcache.c:1195 [inline] shrink_dentry_list+0x180/0x5e0 fs/dcache.c:1222 shrink_dcache_tree+0x3b1/0x7e0 fs/dcache.c:1653 shrink_dcache_parent fs/dcache.c:1693 [inline] d_invalidate fs/dcache.c:1775 [inline] d_invalidate+0x13a/0x290 fs/dcache.c:1760 lookup_fast+0x3f4/0x600 fs/namei.c:1880 walk_component fs/namei.c:2274 [inline] link_path_walk+0x7d4/0x1cc0 fs/namei.c:2652 path_openat+0x1be/0x31a0 fs/namei.c:4854 do_file_open+0x20e/0x430 fs/namei.c:4887 do_sys_openat2+0x10d/0x1e0 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_openat fs/open.c:1386 [inline] __se_sys_openat fs/open.c:1381 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1381 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f64ee6a7407 RSP: 002b:00007ffde58e9e20 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f64eee19880 RCX: 00007f64ee6a7407 RDX: 0000000000080000 RSI: 00007ffde58e9fa0 RDI: ffffffffffffff9c RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055b2196387f5 R13: 000055b2196387f5 R14: 0000000000000001 R15: 0000000000000000 rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g115953 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=61254 rcu: rcu_preempt kthread starved for 10505 jiffies! g115953 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28216 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2297 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 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: 16540 Comm: syz.4.2949 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:__lock_release kernel/locking/lockdep.c:5536 [inline] RIP: 0010:lock_release kernel/locking/lockdep.c:5889 [inline] RIP: 0010:lock_release+0xdb/0x310 kernel/locking/lockdep.c:5875 Code: 0f 84 ad 00 00 00 45 8b bc 24 88 0b 00 00 45 85 ff 0f 84 9c 01 00 00 48 8d 4c 24 0c 44 89 fa 48 89 de 4c 89 e7 e8 75 88 ff ff <48> 85 c0 0f 84 80 01 00 00 8b 50 24 85 d2 0f 85 df 01 00 00 66 83 RSP: 0018:ffffc90000007e28 EFLAGS: 00000002 RAX: ffff88802fd98b90 RBX: ffff8880b84284d8 RCX: ffffc90000007e34 RDX: 0000000000000001 RSI: ffff8880b84284d8 RDI: ffff88802fd98b90 RBP: ffffffff81f47f93 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88802fd98000 R13: 0000000000000001 R14: 0000000000000087 R15: 0000000000000001 FS: 00007f74f8f0e6c0(0000) GS:ffff888124383000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000035118000 CR4: 00000000003526f0 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:176 [inline] _raw_spin_unlock_irqrestore+0x1a/0x80 kernel/locking/spinlock.c:198 __run_hrtimer kernel/time/hrtimer.c:1926 [inline] __hrtimer_run_queues+0x383/0xa00 kernel/time/hrtimer.c:1994 hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2113 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] __sysvec_apic_timer_interrupt+0x10b/0x460 arch/x86/kernel/apic/apic.c:1067 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0x9e/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:ktime_mono_to_any+0x40/0x90 kernel/time/timekeeping.c:1057 Code: 02 77 4d 4a 8d 3c e5 00 e7 b2 8b 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 49 4a 8b 1c e5 00 e7 b2 8b <48> b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 80 3c 02 00 75 RSP: 0018:ffffc90003b0fc48 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffffff9b197f10 RCX: ffffc900060da000 RDX: 1ffffffff1765ce0 RSI: ffffffff81f4efd3 RDI: ffffffff8bb2e700 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000080000000 R11: 0000000000000000 R12: 0000000000000000 R13: 1ffff92000761f9f R14: 0000000000000000 R15: 0000000000000000 ktime_mono_to_real include/linux/timekeeping.h:165 [inline] timerfd_clock_was_set+0x1c/0x310 fs/timerfd.c:97 clock_was_set+0x661/0x870 kernel/time/hrtimer.c:1004 do_settimeofday64+0x330/0x4d0 kernel/time/timekeeping.c:1603 do_sys_settimeofday64+0x1dc/0x260 kernel/time/time.c:195 __do_sys_clock_settime kernel/time/posix-timers.c:1124 [inline] __se_sys_clock_settime kernel/time/posix-timers.c:1108 [inline] __x64_sys_clock_settime+0x1c1/0x2a0 kernel/time/posix-timers.c:1108 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f74f7f9ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f74f8f0e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: ffffffffffffffda RBX: 00007f74f8215fa0 RCX: 00007f74f7f9ce59 RDX: 0000000000000000 RSI: 0000200000000240 RDI: 0000000000000000 RBP: 00007f74f8032d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f74f8216038 R14: 00007f74f8215fa0 R15: 00007ffc99b9bad8