sched: DL replenish lagged too much rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=6474/1/0x4000000000000000 softirq=20574/20575 fqs=1 rcu: (detected by 1, t=10505 jiffies, g=16709, q=437 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6950 Comm: sed Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:do_raw_write_seqcount_barrier include/linux/seqlock.h:576 [inline] RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1803 [inline] RIP: 0010:__hrtimer_run_queues+0x696/0xc60 kernel/time/hrtimer.c:1841 Code: 24 18 48 8b 74 24 30 42 0f b6 04 2e 84 c0 48 8b 54 24 20 0f 85 9c 01 00 00 ff 02 42 0f b6 04 2e 84 c0 0f 85 b6 01 00 00 ff 02 <48> 8b 44 24 48 42 80 3c 28 00 74 08 48 89 df e8 76 90 76 00 4c 39 RSP: 0018:ffffc90000007d40 EFLAGS: 00000006 RAX: 0000000000000000 RBX: ffff8880b8627bc8 RCX: 0000000000000000 RDX: ffff8880b8627b90 RSI: 1ffff110170c4f72 RDI: ffff88802bdae340 RBP: ffffc90000007e90 R08: ffff88802bdae357 R09: 0000000000000000 R10: ffff88802bdae340 R11: ffffed10057b5c6b R12: ffff88802bdae340 R13: dffffc0000000000 R14: ffff8880b8627bd8 R15: ffff8880b8627b80 FS: 0000000000000000(0000) GS:ffff8881259e8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb442e62368 CR3: 000000000e138000 CR4: 00000000003526f0 Call Trace: hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline] __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:331 [inline] RIP: 0010:rcu_read_lock include/linux/rcupdate.h:841 [inline] RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1169 [inline] RIP: 0010:unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 Code: 00 e8 c2 52 33 00 4c 8d 3d 00 00 00 00 48 c7 c7 20 c8 33 8e 31 f6 31 d2 b9 02 00 00 00 45 31 c0 45 31 c9 41 57 e8 5e 9e 29 00 <48> 83 c4 08 e8 95 4b 0f 0a 85 c0 74 3a e8 fc 98 32 00 84 c0 75 31 RSP: 0018:ffffc9001c11f290 EFLAGS: 00000282 RAX: a3e2df1b464f7500 RBX: ffffffff8173e5c8 RCX: a3e2df1b464f7500 RDX: 0000000000000000 RSI: ffffffff8ddae1af RDI: ffffffff8c036f00 RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff8173bd25 R10: ffffc9001c11f3c8 R11: fffff52003823e85 R12: 1ffff92003823e79 R13: ffffc9001c11f400 R14: ffffc9001c11f3c8 R15: ffffffff8173bd25 __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x3d5/0x6f0 mm/slub.c:5457 kmalloc_noprof include/linux/slab.h:956 [inline] slab_free_hook mm/slub.c:2426 [inline] slab_free mm/slub.c:6181 [inline] kmem_cache_free+0x171/0x690 mm/slub.c:6292 anon_vma_free mm/rmap.c:136 [inline] __put_anon_vma+0x12b/0x2d0 mm/rmap.c:2781 put_anon_vma include/linux/rmap.h:117 [inline] unlink_anon_vmas+0x503/0x670 mm/rmap.c:443 free_pgtables+0x72b/0x9c0 mm/memory.c:413 exit_mmap+0x43c/0xb40 mm/mmap.c:1291 __mmput+0x118/0x430 kernel/fork.c:1148 exit_mm+0x1da/0x2c0 kernel/exit.c:582 do_exit+0x648/0x2300 kernel/exit.c:954 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107 __do_sys_exit_group kernel/exit.c:1118 [inline] __se_sys_exit_group kernel/exit.c:1116 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1116 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd72f54d6c5 Code: Unable to access opcode bytes at 0x7fd72f54d69b. RSP: 002b:00007ffe03b16308 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007fd72f64efe8 RCX: 00007fd72f54d6c5 RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd72f64d680 R15: 00007fd72f64f000 rcu: rcu_preempt kthread starved for 10500 jiffies! g16709 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:27528 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7046 [inline] schedule+0x165/0x360 kernel/sched/core.c:7061 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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: CPU: 1 UID: 0 PID: 6002 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:__sanitizer_cov_trace_pc+0x5d/0x70 kernel/kcov.c:235 Code: 58 16 00 00 83 fa 02 75 21 48 8b 91 60 16 00 00 48 8b 32 48 8d 7e 01 8b 89 5c 16 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 8e 2e c6 09 cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 RSP: 0018:ffffc90004b17918 EFLAGS: 00000293 RAX: ffffffff81b443cb RBX: 1ffff110170c8355 RCX: ffff888033b91e40 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90004b17aa0 R08: ffffffff8fc3f337 R09: 1ffffffff1f87e66 R10: dffffc0000000000 R11: fffffbfff1f87e67 R12: ffff8880b8641aa8 R13: dffffc0000000000 R14: ffff8880b873b1c0 R15: 0000000000000000 FS: 00007f94ea957880(0000) GS:ffff888125ae8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f94ea956000 CR3: 0000000032ec8000 CR4: 00000000003526f0 Call Trace: csd_lock_wait kernel/smp.c:342 [inline] smp_call_function_many_cond+0xd4b/0x12d0 kernel/smp.c:877 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline] flush_tlb_mm_range+0x6b1/0x12d0 arch/x86/mm/tlb.c:1451 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline] tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497 do_mprotect_pkey+0x9f5/0xcd0 mm/mprotect.c:999 __do_sys_mprotect mm/mprotect.c:1012 [inline] __se_sys_mprotect mm/mprotect.c:1009 [inline] __x64_sys_mprotect+0x80/0x90 mm/mprotect.c:1009 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f94eaa59fe7 Code: ef e8 3d fa ff ff 84 c0 75 b9 31 db 48 83 c4 08 48 89 d8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 0f 1f 44 00 00 b8 0a 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 2d 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007ffeb8df4e98 EFLAGS: 00000246 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 0000000000000200 RCX: 00007f94eaa59fe7 RDX: 0000000000000001 RSI: 0000000000000200 RDI: 00007f94ea956000 RBP: 000055ff0bfc2050 R08: 0000000000000000 R09: 0000000000000200 R10: 000055ff0bfc20b0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000ff0000 R14: 000055ff0bfc41f8 R15: 00007f94eabfc39c