rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=cabc/1/0x4000000000000000 softirq=74968/74968 fqs=0 rcu: (detected by 0, t=10505 jiffies, g=82273, q=909 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13344 Comm: syz.3.2369 Not tainted 6.14.0-syzkaller-05877-g1a9239bb4253 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:arch_local_irq_save arch/x86/include/asm/irqflags.h:124 [inline] RIP: 0010:lock_release+0x8f/0x2f0 kernel/locking/lockdep.c:5883 Code: 01 00 00 65 4c 8b 35 d8 3f 06 12 41 8b b6 ec 0a 00 00 85 f6 0f 85 ff 00 00 00 48 81 3b 80 fb a4 93 0f 84 f2 00 00 00 9c 41 5d 48 c7 c7 5f 7a ca 8d e8 34 6b ca 09 65 ff 05 15 7d 06 12 8b 0d RSP: 0018:ffffc90000a08cc0 EFLAGS: 00000006 RAX: 0000000000000000 RBX: ffffffff9ad6ab98 RCX: 1ffff1100aeac1a6 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000002 R08: 0000000000000001 R09: fffff52000141192 R10: 0000000000000002 R11: ffffffff9ad6ab80 R12: ffffffff84cc923c R13: 0000000000000006 R14: ffff88802a7ba440 R15: 1ffff920001411a8 FS: 0000555568076500(0000) GS:ffff888124b3d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000000afc0 CR3: 000000002a40e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x1a/0x80 kernel/locking/spinlock.c:194 debug_object_activate+0x2ec/0x4c0 lib/debugobjects.c:836 debug_hrtimer_activate kernel/time/hrtimer.c:445 [inline] debug_activate kernel/time/hrtimer.c:486 [inline] enqueue_hrtimer+0x23/0x3b0 kernel/time/hrtimer.c:1090 __run_hrtimer kernel/time/hrtimer.c:1808 [inline] __hrtimer_run_queues+0x8ff/0xad0 kernel/time/hrtimer.c:1855 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1917 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x108/0x3f0 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:194 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 36 0a 33 f6 48 89 df e8 ae 5d 33 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 85 d2 23 f6 65 8b 05 6e 4a 39 08 85 c0 74 16 5b RSP: 0018:ffffc9000520fc18 EFLAGS: 00000246 RAX: 0000000000000006 RBX: ffffffff9acbe1a0 RCX: ffffffff81c2c6cf RDX: 0000000000000000 RSI: ffffffff8dbb7ded RDI: ffffffff8bf377c0 RBP: 0000000000000206 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff9082de17 R11: ffffffff9acbe1a0 R12: 0000000000000001 R13: ffff888028a5dc80 R14: dffffc0000000000 R15: 1ffff92000a41f8a debug_object_activate+0x2ec/0x4c0 lib/debugobjects.c:836 debug_rcu_head_queue kernel/rcu/rcu.h:224 [inline] __call_rcu_common.constprop.0+0x2c/0x9f0 kernel/rcu/tree.c:3067 slab_free_hook mm/slub.c:2340 [inline] slab_free mm/slub.c:4633 [inline] kmem_cache_free+0x173/0x4d0 mm/slub.c:4735 file_free fs/file_table.c:76 [inline] __fput+0x68d/0xb70 fs/file_table.c:478 task_work_run+0x14d/0x240 kernel/task_work.c:227 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/0x260 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f421d18d169 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:00007fff0e839068 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 000000000008e55f RCX: 00007f421d18d169 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f421d3a7ba0 R08: 0000000000000001 R09: 0000001e0e83935f R10: 00007f421d000000 R11: 0000000000000246 R12: 00007f421d3a5fac R13: 00007f421d3a5fa0 R14: ffffffffffffffff R15: 00007fff0e839180 rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g82273 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=48850 rcu: rcu_preempt kthread starved for 10505 jiffies! g82273 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:28056 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5366 [inline] __schedule+0x1129/0x5c00 kernel/sched/core.c:6747 __schedule_loop kernel/sched/core.c:6824 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6839 schedule_timeout+0x123/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248 kthread+0x3a4/0x760 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245