rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=fcc4/1/0x4000000000000000 softirq=91395/91407 fqs=1 rcu: (detected by 1, t=10505 jiffies, g=70765, q=1518 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 22501 Comm: syz.3.3871 Not tainted 6.13.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:validate_chain+0xed/0x5920 kernel/locking/lockdep.c:3871 Code: f3 48 89 b4 24 b0 00 00 00 4c 8d 6e 20 4c 89 e8 48 c1 e8 03 48 89 44 24 60 42 0f b6 04 20 84 c0 0f 85 ef 4c 00 00 41 8b 5d 00 <89> d8 25 00 80 04 00 3d 00 00 04 00 0f 85 80 04 00 00 81 e3 ff 1f RSP: 0018:ffffc90000007200 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 00000000000c6000 RCX: 1ffff92000000e60 RDX: 0000000000000000 RSI: ffff88807ea48b80 RDI: ffff88807ea48000 RBP: ffffc90000007500 R08: ffffffff94271887 R09: 1ffffffff284e310 R10: dffffc0000000000 R11: fffffbfff284e311 R12: dffffc0000000000 R13: ffff88807ea48ba0 R14: 71a5d68fa1cc311c R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2d1d57 CR3: 000000000e736000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 debug_object_deactivate+0x158/0x390 lib/debugobjects.c:873 debug_hrtimer_deactivate kernel/time/hrtimer.c:433 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:475 __run_hrtimer kernel/time/hrtimer.c:1707 [inline] __hrtimer_run_queues+0x305/0xd30 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 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+0x52/0xc0 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_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202 Code: 90 f3 0f 1e fa 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 0a 09 b7 f5 48 89 df e8 42 50 b8 f5 e8 7d 5e e3 f5 fb bf 01 00 00 00 62 b5 a9 f5 65 8b 05 e3 06 40 74 85 c0 74 06 5b c3 cc cc cc cc RSP: 0018:ffffc90000007c90 EFLAGS: 00000286 RAX: 007427c5b4330000 RBX: ffff8880b862a700 RCX: ffffffff817b27ea RDX: dffffc0000000000 RSI: ffffffff8c0a9840 RDI: 0000000000000001 RBP: ffffc90000007df0 R08: ffffffff94271887 R09: 1ffffffff284e310 R10: dffffc0000000000 R11: fffffbfff284e311 R12: ffffffff89ac9610 R13: ffffc90000007d40 R14: ffff88807d0ea830 R15: ffff88807d0ea810 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2418 [inline] __run_timer_base+0x65a/0x8e0 kernel/time/timer.c:2430 run_timer_base kernel/time/timer.c:2439 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2449 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:kasan_check_range+0x7/0x290 mm/kasan/generic.c:188 Code: 06 8e e8 6c b6 e3 ff 90 0f 0b 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 41 57 <41> 56 41 54 53 b0 01 48 85 f6 0f 84 a0 01 00 00 4c 8d 04 37 49 39 RSP: 0018:ffffc9000ebc7278 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81dc1162 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea000141e480 RBP: 0000000000000000 R08: ffffffff81dc114b R09: 1ffffd4000283c90 R10: dffffc0000000000 R11: fffff94000283c91 R12: dffffc0000000000 R13: ffffea000141e480 R14: ffffea000141e488 R15: 1ffffd4000283c91 instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] folio_test_lru include/linux/page-flags.h:516 [inline] folio_mark_accessed+0x1d2/0x9c0 mm/swap.c:450 zap_present_folio_ptes mm/memory.c:1511 [inline] zap_present_ptes mm/memory.c:1585 [inline] zap_pte_range mm/memory.c:1627 [inline] zap_pmd_range mm/memory.c:1753 [inline] zap_pud_range mm/memory.c:1782 [inline] zap_p4d_range mm/memory.c:1803 [inline] unmap_page_range+0x18de/0x4040 mm/memory.c:1824 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1914 exit_mmap+0x275/0xc20 mm/mmap.c:1672 __mmput+0x115/0x3b0 kernel/fork.c:1348 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+0x16b2/0x1750 kernel/signal.c:3017 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_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdf8cb85d29 Code: Unable to access opcode bytes at 0x7fdf8cb85cff. RSP: 002b:00007fdf8d9a90e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007fdf8cd76168 RCX: 00007fdf8cb85d29 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fdf8cd76168 RBP: 00007fdf8cd76160 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdf8cd7616c R13: 0000000000000000 R14: 00007fffe5d1cd50 R15: 00007fffe5d1ce38 rcu: rcu_preempt kthread starved for 10500 jiffies! g70765 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:25208 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 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: 3556 Comm: kworker/u8:10 Not tainted 6.13.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x19f3/0x2c60 kernel/smp.c:884 Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 c6 e6 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 71 e2 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 55 e2 RSP: 0018:ffffc9000d5b76e0 EFLAGS: 00000293 RAX: ffffffff81938f8b RBX: 1ffff110170c8c65 RCX: ffff888032578000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9000d5b78e0 R08: ffffffff81938f5a R09: 1ffffffff284e310 R10: dffffc0000000000 R11: fffffbfff284e311 R12: dffffc0000000000 R13: ffff8880b8646328 R14: ffff8880b873f940 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f964ea3ab08 CR3: 000000000e736000 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:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2114 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522 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:849 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244