rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (0 ticks this GP) idle=4e7c/1/0x4000000000000000 softirq=65453/65458 fqs=501 rcu: (detected by 1, t=10502 jiffies, g=52529, q=665 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 16157 Comm: syz.5.2260 Not tainted 6.13.0-rc1-syzkaller-00025-gfeffde684ac2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:separate_irq_context kernel/locking/lockdep.c:5087 [inline] RIP: 0010:__lock_acquire+0x1589/0x3c40 kernel/locking/lockdep.c:5210 Code: e8 0e 85 ff 0f 84 64 0b 00 00 90 31 d2 e9 10 f9 ff ff c7 44 24 58 fe ff ff ff c7 44 24 68 ff ff ff ff c7 44 24 60 ff ff ff ff 44 24 40 ff ff ff ff c7 84 24 84 00 00 00 01 00 00 00 e9 d2 f5 RSP: 0018:ffffc90000007b38 EFLAGS: 00000002 RAX: 0000000000000000 RBX: 98dd3d2fa28c38ba RCX: ffffffff81767932 RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff8880303d0b51 RBP: 0000000000000040 R08: 0000000000000000 R09: fffffbfff2dca3cc R10: ffffffff96e51e67 R11: 0000000000000003 R12: ffff8880303d0b29 R13: ffff8880303d0000 R14: 0000000000000003 R15: ffff8880303d0b30 FS: 00005555751ba500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000012390000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] advance_sched+0xd8/0xc60 net/sched/sch_taprio.c:924 __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire.part.0+0x155/0x380 kernel/locking/lockdep.c:5814 Code: b8 ff ff ff ff 65 0f c1 05 f0 cf 8b 7e 83 f8 01 0f 85 d0 01 00 00 9c 58 f6 c4 02 0f 85 e5 01 00 00 48 85 ed 0f 85 b6 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc9000cbc7a90 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff92001978f53 RCX: ffffffff8175c37e RDX: 0000000000000001 RSI: ffffffff8b6cdb40 RDI: ffffffff8bd1b4a0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dca39c R10: ffffffff96e51ce7 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88807e5b23d0 R14: 0000000000000000 R15: 0000000000000000 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] _atomic_dec_and_lock+0xd2/0x120 lib/dec_and_lock.c:28 iput fs/inode.c:1964 [inline] iput+0xc7/0x890 fs/inode.c:1958 dentry_unlink_inode+0x29c/0x480 fs/dcache.c:422 __dentry_kill+0x1d0/0x600 fs/dcache.c:625 dput.part.0+0x4b1/0x9b0 fs/dcache.c:867 dput+0x1f/0x30 fs/dcache.c:857 find_next_child fs/libfs.c:611 [inline] simple_recursive_removal+0x131/0x8e0 fs/libfs.c:626 debugfs_remove+0x5d/0x80 fs/debugfs/inode.c:812 kvm_destroy_vm_debugfs+0xc6/0x250 virt/kvm/kvm_main.c:987 kvm_destroy_vm virt/kvm/kvm_main.c:1266 [inline] kvm_put_kvm+0xf1/0xb40 virt/kvm/kvm_main.c:1340 kvm_vm_release+0x3c/0x50 virt/kvm/kvm_main.c:1363 __fput+0x3f8/0xb60 fs/file_table.c:450 task_work_run+0x14e/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x27b/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f034037ff19 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:00007ffd15e352e8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00000000000d8606 RCX: 00007f034037ff19 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f0340547ba0 R08: 0000000000000001 R09: 00007ffd15e355cf R10: 00007f0340200000 R11: 0000000000000246 R12: 00000000000d8caa R13: 00007f0340545fa0 R14: 0000000000000032 R15: ffffffffffffffff rcu: rcu_preempt kthread starved for 7995 jiffies! g52529 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:28424 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 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: 0 Comm: swapper/1 Not tainted 6.13.0-rc1-syzkaller-00025-gfeffde684ac2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:92 [inline] RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 d8 f4 d9 74 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 48 68 b3 00 fb f4 c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc900001a7d58 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8b29c759 RDX: 0000000000000001 RSI: ffff888144ea8800 RDI: ffff888144ea8864 RBP: ffff888144ea8864 R08: 0000000000000001 R09: ffffed10170e6fed R10: ffff8880b8737f6b R11: 0000000000000000 R12: ffff88801f741800 R13: ffffffff8ee14960 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000564cefccf060 CR3: 0000000029ffa000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:699 cpuidle_enter_state+0xaa/0x4f0 drivers/cpuidle/cpuidle.c:268 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:389 cpuidle_idle_call kernel/sched/idle.c:230 [inline] do_idle+0x310/0x3f0 kernel/sched/idle.c:325 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423 start_secondary+0x222/0x2b0 arch/x86/kernel/smpboot.c:314 common_startup_64+0x13e/0x148