rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P844/1:b..l P848/1:b..l rcu: (detected by 0, t=10502 jiffies, g=179657, q=113 ncpus=2) task:syz.7.6966 state:R running task stack:24208 pid:848 tgid:846 ppid:29461 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17fa/0x4bd0 kernel/sched/core.c:6690 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6869 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6893 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] zap_pte_range mm/memory.c:1691 [inline] zap_pmd_range mm/memory.c:1739 [inline] zap_pud_range mm/memory.c:1768 [inline] zap_p4d_range mm/memory.c:1789 [inline] unmap_page_range+0x36b1/0x40e0 mm/memory.c:1810 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900 exit_mmap+0x275/0xc40 mm/mmap.c:1913 __mmput+0x115/0x380 kernel/fork.c:1348 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x28e0 kernel/exit.c:926 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 get_signal+0x16a3/0x1740 kernel/signal.c:2917 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:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff98d17e719 RSP: 002b:00007ff98dfa40e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007ff98d335f88 RCX: 00007ff98d17e719 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007ff98d335f8c RBP: 00007ff98d335f80 R08: 7fffffffffffffff R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff98d335f8c R13: 0000000000000000 R14: 00007ffe69bed8f0 R15: 00007ffe69bed9d8 task:syz.3.6963 state:R running task stack:26640 pid:844 tgid:844 ppid:837 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17fa/0x4bd0 kernel/sched/core.c:6690 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6869 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6893 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] zap_pte_range mm/memory.c:1691 [inline] zap_pmd_range mm/memory.c:1739 [inline] zap_pud_range mm/memory.c:1768 [inline] zap_p4d_range mm/memory.c:1789 [inline] unmap_page_range+0x36b1/0x40e0 mm/memory.c:1810 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900 exit_mmap+0x275/0xc40 mm/mmap.c:1913 __mmput+0x115/0x380 kernel/fork.c:1348 exit_mm+0x220/0x310 kernel/exit.c:571 do_exit+0x9b2/0x28e0 kernel/exit.c:926 __do_sys_exit kernel/exit.c:1055 [inline] __se_sys_exit kernel/exit.c:1053 [inline] __x64_sys_exit+0x40/0x40 kernel/exit.c:1053 x64_sys_call+0x2622/0x2640 arch/x86/include/generated/asm/syscalls_64.h:61 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: 0033:0x7fc0e5d7e719 RSP: 002b:00007fc0e6bbafe8 EFLAGS: 00000246 ORIG_RAX: 000000000000003c RAX: ffffffffffffffda RBX: 00007fc0e5f35f80 RCX: 00007fc0e5d7e719 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fc0e5df139e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc0e5f35f80 R15: 00007ffef5ce48c8 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g179657 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=151864 rcu: rcu_preempt kthread starved for 10502 jiffies! g179657 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:25920 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17fa/0x4bd0 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6782 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 849 Comm: syz.2.6967 Not tainted 6.12.0-rc6-syzkaller-00272-gda4373fbcf00 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4826 [inline] RIP: 0010:__lock_acquire+0x4dc/0x2050 kernel/locking/lockdep.c:5152 Code: 13 00 00 44 89 3b 44 89 c3 48 89 d8 48 c1 e8 06 48 8d 3c c5 00 88 29 94 be 08 00 00 00 e8 2c 2c 8b 00 48 0f a3 1d 44 35 b9 12 <73> 27 48 69 c3 c8 00 00 00 48 8d 98 c0 06 c1 93 48 ba 00 00 00 00 RSP: 0018:ffffc90000a18a30 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000022 RCX: ffffffff817052b4 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff94298800 RBP: 000000000000000f R08: ffffffff94298807 R09: 1ffffffff2853100 R10: dffffc0000000000 R11: fffffbfff2853101 R12: ffff88802f690000 R13: 0000000000000022 R14: 00000000000a4022 R15: 0000000000000000 FS: 00007fc20cc646c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000003fd7a000 CR4: 00000000003526f0 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] advance_sched+0xa1e/0xca0 net/sched/sch_taprio.c:985 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x59b/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 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:unwind_next_frame+0x315/0x22d0 arch/x86/kernel/unwind_orc.c:505 Code: 64 48 01 d2 48 01 f2 0f 84 42 01 00 00 48 8d 5a 04 4c 8d 72 05 48 89 d8 48 c1 e8 03 48 bd 00 00 00 00 00 fc ff df 0f b6 04 28 <84> c0 0f 85 58 18 00 00 4c 89 f0 48 c1 e8 03 0f b6 04 28 84 c0 0f RSP: 0018:ffffc9000ca56a30 EFLAGS: 00000a03 RAX: 0000000000000000 RBX: ffffffff91467616 RCX: ffffffff909a4c7c RDX: ffffffff91467612 RSI: ffffffff91467612 RDI: 0000000000000001 RBP: dffffc0000000000 R08: 0000000000000021 R09: ffffc9000ca56bf0 R10: ffffc9000ca56b50 R11: ffffffff81809260 R12: 0000000000000000 R13: ffffc9000ca56b00 R14: ffffffff91467617 R15: ffffffff8be0012f arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __set_page_owner+0x92/0x800 mm/page_owner.c:320 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x3033/0x3180 mm/page_alloc.c:3457 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 get_free_pages_noprof+0xc/0x30 mm/page_alloc.c:4780 tlb_next_batch mm/mmu_gather.c:35 [inline] __tlb_remove_folio_pages_size+0x2a5/0x590 mm/mmu_gather.c:196 zap_present_folio_ptes mm/memory.c:1525 [inline] zap_present_ptes mm/memory.c:1579 [inline] zap_pte_range mm/memory.c:1621 [inline] zap_pmd_range mm/memory.c:1739 [inline] zap_pud_range mm/memory.c:1768 [inline] zap_p4d_range mm/memory.c:1789 [inline] unmap_page_range+0x1aca/0x40e0 mm/memory.c:1810 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900 exit_mmap+0x275/0xc40 mm/mmap.c:1913 __mmput+0x115/0x380 kernel/fork.c:1348 copy_process+0x28da/0x3d50 kernel/fork.c:2635 kernel_clone+0x223/0x880 kernel/fork.c:2786 __do_sys_clone kernel/fork.c:2929 [inline] __se_sys_clone kernel/fork.c:2913 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2913 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: 0033:0x7fc20bd7e719 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:00007fc20cc63fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fc20bf35f80 RCX: 00007fc20bd7e719 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000001000 RBP: 00007fc20bdf139e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc20bf35f80 R15: 00007ffeef9b7e78