rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=7b94/1/0x4000000000000000 softirq=65651/65652 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6154/1:b..l P11824/1:b..l rcu: (detected by 1, t=10505 jiffies, g=63749, q=2054 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11838 Comm: syz.7.1678 Not tainted 6.14.0-rc4-syzkaller-00199-g76544811c850 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:lock_acquire+0x113/0x550 kernel/locking/lockdep.c:5824 Code: 4d 28 89 0e 00 0f 84 f9 02 00 00 48 c7 c0 10 f6 3b 90 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 ff 02 00 00 83 3d ad 43 9f 0e 00 <0f> 84 42 01 00 00 65 8b 05 10 d8 65 7e 85 c0 0f 85 8f 01 00 00 65 RSP: 0018:ffffc90000007b40 EFLAGS: 00000002 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff819cb224 RDX: 0000000000000000 RSI: ffffffff8c801b20 RDI: ffffffff8c801ae0 RBP: ffffc90000007c88 R08: ffffffff903bc377 R09: 1ffffffff207786e R10: dffffc0000000000 R11: fffffbfff207786f R12: 1ffff92000000f70 R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000 FS: 00007f8388bc86c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f815ff8 CR3: 000000005a226000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1805 [inline] __hrtimer_run_queues+0x670/0xd30 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 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+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 2e 2d 23 f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 13 1e 8c f5 65 8b 05 54 90 00 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc90004f67ba0 EFLAGS: 00000206 RAX: f93cfb8124f73500 RBX: 1ffff920009ecf78 RCX: ffffffff819d2aaa RDX: dffffc0000000000 RSI: ffffffff8c2aa4a0 RDI: 0000000000000001 RBP: ffffc90004f67c30 R08: ffffffff94513847 R09: 1ffffffff28a2708 R10: dffffc0000000000 R11: fffffbfff28a2709 R12: dffffc0000000000 R13: 1ffff920009ecf74 R14: ffffc90004f67bc0 R15: 0000000000000246 clock_was_set+0x686/0x810 kernel/time/hrtimer.c:984 do_settimeofday64+0x343/0x5e0 kernel/time/timekeeping.c:1381 __do_sys_clock_settime kernel/time/posix-timers.c:1135 [inline] __se_sys_clock_settime kernel/time/posix-timers.c:1119 [inline] __x64_sys_clock_settime+0x23a/0x280 kernel/time/posix-timers.c:1119 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8387d8d169 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:00007f8388bc8038 EFLAGS: 00000246 ORIG_RAX: 00000000000000e3 RAX: ffffffffffffffda RBX: 00007f8387fa6160 RCX: 00007f8387d8d169 RDX: 0000000000000000 RSI: 0000400000000180 RDI: 0000000000000000 RBP: 00007f8387e0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8387fa6160 R15: 00007ffc8647eca8 task:syz.5.1675 state:R running task stack:23824 pid:11824 tgid:11821 ppid:5975 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x18bc/0x4c40 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] finish_fault+0xa76/0x11d0 mm/memory.c:5273 do_read_fault mm/memory.c:5407 [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+0x4c6f/0x70f0 mm/memory.c:6043 handle_mm_fault+0x2c1/0x7e0 mm/memory.c:6212 faultin_page mm/gup.c:1196 [inline] __get_user_pages+0x1a92/0x4140 mm/gup.c:1491 populate_vma_page_range+0x264/0x330 mm/gup.c:1929 __mm_populate+0x27a/0x460 mm/gup.c:2032 mm_populate include/linux/mm.h:3386 [inline] vm_mmap_pgoff+0x303/0x430 mm/util.c:580 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efc93d8d169 RSP: 002b:00007efc94ba6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007efc93fa6160 RCX: 00007efc93d8d169 RDX: 000000000000000c RSI: 0000000000800000 RDI: 0000400000800000 RBP: 00007efc93e0e2a0 R08: ffffffffffffffff R09: 0000000000000000 R10: 000000000000a031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007efc93fa6160 R15: 00007ffddf5e5c38 task:syz-executor state:R running task stack:20544 pid:6154 tgid:6154 ppid:6138 task_flags:0x400140 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x18bc/0x4c40 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] copy_pte_range mm/memory.c:1201 [inline] copy_pmd_range+0x6ddc/0x77b0 mm/memory.c:1262 copy_pud_range mm/memory.c:1299 [inline] copy_p4d_range mm/memory.c:1323 [inline] copy_page_range+0x99f/0xe90 mm/memory.c:1421 dup_mmap kernel/fork.c:748 [inline] dup_mm kernel/fork.c:1700 [inline] copy_mm+0x1269/0x2160 kernel/fork.c:1752 copy_process+0x17d1/0x3cf0 kernel/fork.c:2403 kernel_clone+0x223/0x870 kernel/fork.c:2815 __do_sys_clone kernel/fork.c:2958 [inline] __se_sys_clone kernel/fork.c:2942 [inline] __x64_sys_clone+0x267/0x2e0 kernel/fork.c:2942 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5bccf839d3 RSP: 002b:00007ffdf9586f18 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5bccf839d3 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000555568d957d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000927c0 R14: 000000000007dd4f R15: 00007ffdf95870b0 rcu: rcu_preempt kthread starved for 10505 jiffies! g63749 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:24944 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x18bc/0x4c40 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 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 8361 Comm: kworker/u8:11 Not tainted 6.14.0-rc4-syzkaller-00199-g76544811c850 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1ba4/0x2d30 kernel/smp.c:885 Code: 03 84 c0 75 7e 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 30 f5 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 e0 f0 0b 00 eb 41 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 11 41 f7 45 00 RSP: 0018:ffffc90002f77640 EFLAGS: 00000293 RAX: ffffffff81b5ce25 RBX: 1ffff110170c8c75 RCX: ffff888026211e00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90002f77840 R08: ffffffff81b5cdf0 R09: 1ffffffff28a2708 R10: dffffc0000000000 R11: fffffbfff28a2709 R12: ffff8880b873f9c8 R13: ffff8880b86463a8 R14: ffff8880b873f9c0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0197a3967b CR3: 000000000e938000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 00000000ffff000b DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2118 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2328 text_poke_flush arch/x86/kernel/alternative.c:2519 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2526 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x136/0x260 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xbc/0x260 mm/kfence/core.c:850 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd30 kernel/workqueue.c:3400 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