rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=3cd4/1/0x4000000000000000 softirq=211648/211656 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P911/1:b..l rcu: (detected by 1, t=10505 jiffies, g=176641, q=168 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 3995 Comm: syz.0.7462 Not tainted 6.16.0-rc3-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:227 [inline] 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:638 [inline] RIP: 0010:cpu_online include/linux/cpumask.h:1197 [inline] RIP: 0010:trace_hrtimer_expire_entry include/trace/events/timer.h:259 [inline] RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1758 [inline] RIP: 0010:__hrtimer_run_queues+0x459/0xc60 kernel/time/hrtimer.c:1825 Code: 00 00 e8 1a ed 11 00 45 89 ef 41 c1 ed 06 4a 8d 3c ed f0 e0 9f 8f be 08 00 00 00 e8 01 47 73 00 31 f6 4c 0f a3 3d c7 81 f1 0d <41> 0f 92 c7 40 0f 92 c6 bf 02 00 00 00 e8 e5 ef 11 00 45 84 ff 74 RSP: 0018:ffffc90000007d40 EFLAGS: 00000047 RAX: ffffffff81ae5f01 RBX: ffff8880b8627d08 RCX: ffffffff81ae5f1f RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8f9fe0f0 RBP: ffffc90000007e90 R08: ffffffff8f9fe0f7 R09: 1ffffffff1f3fc1e R10: dffffc0000000000 R11: fffffbfff1f3fc1f R12: ffff88803031a340 R13: 0000000000000000 R14: ffffffff897ed730 R15: 0000000000000000 FS: 00007f69499b96c0(0000) GS:ffff888125c85000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2f6fa8 CR3: 000000006b402000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 0000000000000047 DR2: 0000000000000005 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 6b 13 66 f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 33 fe 2e f6 65 8b 05 2c eb 37 07 85 c0 74 40 48 c7 04 24 0e 36 RSP: 0018:ffffc90005217a00 EFLAGS: 00000206 RAX: 6a9832141bf69e00 RBX: 0000000000000a02 RCX: 6a9832141bf69e00 RDX: 0000000000000000 RSI: ffffffff8d96eaae RDI: 0000000000000001 RBP: ffffc90005217a90 R08: ffffffff8f9fe0f7 R09: 1ffffffff1f3fc1e R10: dffffc0000000000 R11: fffffbfff1f3fc1f R12: dffffc0000000000 R13: ffffffff8fa653a5 R14: ffffffff99a935e8 R15: 1ffff92000a42f40 class_raw_spinlock_irqsave_destructor include/linux/spinlock.h:557 [inline] timekeeping_inject_offset+0x351/0x4b0 kernel/time/timekeeping.c:1426 do_adjtimex+0x43f/0x9f0 kernel/time/timekeeping.c:2554 do_clock_adjtime kernel/time/posix-timers.c:1162 [inline] __do_sys_clock_adjtime kernel/time/posix-timers.c:1174 [inline] __se_sys_clock_adjtime kernel/time/posix-timers.c:1165 [inline] __x64_sys_clock_adjtime+0x1f4/0x2b0 kernel/time/posix-timers.c:1165 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6948b8e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f69499b9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000131 RAX: ffffffffffffffda RBX: 00007f6948db6160 RCX: 00007f6948b8e929 RDX: 0000000000000000 RSI: 0000200000000480 RDI: 0000000000000000 RBP: 00007f6948c10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f6948db6160 R15: 00007ffea6eed678 task:kworker/0:3 state:R running task stack:25216 pid:911 tgid:911 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events bpf_prog_free_deferred Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7108 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 2b 8e fb 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0000:ffffc90004d874f8 EFLAGS: 00000206 RAX: bcda88043ad76900 RBX: 0000000000000000 RCX: bcda88043ad76900 RDX: 0000000000000000 RSI: ffffffff8db5a830 RDI: ffffffff8be1b840 RBP: ffffffff81728af5 R08: 0000000000000000 R09: ffffffff81728af5 R10: ffffc90004d876b8 R11: ffffffff81ace5b0 R12: 0000000000000002 R13: ffffffff8e13ee60 R14: 0000000000000000 R15: 0000000000000246 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] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 __bpf_prog_free+0xc5/0x120 kernel/bpf/core.c:283 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 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 10505 jiffies! g176641 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:26464 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 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: CPU: 1 UID: 0 PID: 24040 Comm: kworker/u8:4 Not tainted 6.16.0-rc3-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885 Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 60 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 0b 74 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 f0 73 0b RSP: 0018:ffffc9000c5476a0 EFLAGS: 00000293 RAX: ffffffff81b4d830 RBX: ffff8880b873b040 RCX: ffff8880340d8000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000c547800 R08: ffffffff8f9fe0f7 R09: 1ffffffff1f3fc1e R10: dffffc0000000000 R11: fffffbfff1f3fc1f R12: 1ffff110170c835d R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641ae8 FS: 0000000000000000(0000) GS:ffff888125d85000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff08becc7c CR3: 000000000df38000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2691 [inline] smp_text_poke_batch_finish+0x5e0/0x1100 arch/x86/kernel/alternative.c:2901 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x250 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xad/0x240 mm/kfence/core.c:850 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245