rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=385c/1/0x4000000000000000 softirq=12986/12987 fqs=5 rcu: (detected by 0, t=10502 jiffies, g=16617, q=463 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 6144 Comm: syz.1.229 Not tainted 6.11.0-rc2-syzkaller-00011-geb5e56d14912 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:__lock_acquire+0xa/0x2040 kernel/locking/lockdep.c:4995 Code: c1 7c 8f 48 8b 3c 24 e8 94 ef 8a 00 eb 84 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 41 55 41 54 53 <48> 81 ec 90 00 00 00 44 89 4c 24 40 45 89 c5 89 cb 89 f5 49 89 ff RSP: 0018:ffffc90000a189e0 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffffc90000a18aa0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff95108300 RBP: ffffc90000a18b88 R08: 0000000000000001 R09: 0000000000000001 R10: dffffc0000000000 R11: fffffbfff202f82e R12: 1ffff92000143150 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000046 FS: 00005555826bb500(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32214ff8 CR3: 0000000024948000 CR4: 0000000000350ef0 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 __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:764 debug_hrtimer_deactivate kernel/time/hrtimer.c:428 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:484 __run_hrtimer kernel/time/hrtimer.c:1657 [inline] __hrtimer_run_queues+0x305/0xd50 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x112/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:arch_stack_walk+0x114/0x1b0 arch/x86/kernel/stacktrace.c:24 Code: 02 f4 5b 00 48 89 e9 48 8d bd 70 ff ff ff 4c 89 e6 4c 89 fa e8 0d c4 09 00 8b 9d 70 ff ff ff 31 ff 89 de e8 1e f8 5b 00 85 db <74> 4b 4c 8d bd 70 ff ff ff 4c 89 ff e8 6b 92 09 00 48 89 c3 31 ff RSP: 0018:ffffc900090f7960 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff888018770000 RDX: ffff888018770000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900090f79f0 R08: ffffffff81378312 R09: ffffffff814130bf R10: 0000000000000003 R11: ffff888018770000 R12: ffff888018770000 R13: ffffffff817f1d10 R14: ffffc900090f7a40 R15: 0000000000000000 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2252 [inline] slab_free mm/slub.c:4473 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4548 file_free+0x24/0x1f0 fs/file_table.c:65 task_work_run+0x251/0x310 kernel/task_work.c:228 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:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fca099779f9 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:00007ffe396afa68 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 000000000002a10f RCX: 00007fca099779f9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007ffe396afb40 R08: 0000000000000001 R09: 00007ffe396afd4f R10: 00007fca09800000 R11: 0000000000000246 R12: 0000000000000032 R13: 00007ffe396afb60 R14: 00007ffe396afb80 R15: ffffffffffffffff rcu: rcu_preempt kthread starved for 10492 jiffies! g16617 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:24464 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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: 0 UID: 0 PID: 2521 Comm: kworker/u8:6 Not tainted 6.11.0-rc2-syzkaller-00011-geb5e56d14912 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:312 [inline] RIP: 0010:smp_call_function_many_cond+0x1865/0x29d0 kernel/smp.c:856 Code: 89 e6 83 e6 01 31 ff e8 99 14 0c 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 44 10 0c 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 28 10 0c 00 eb e4 44 RSP: 0018:ffffc90008f77700 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 1ffff110172688f9 RCX: ffff888029d73c00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90008f778e0 R08: ffffffff81876697 R09: 1ffffffff26e5900 R10: dffffc0000000000 R11: fffffbfff26e5901 R12: dffffc0000000000 R13: ffff8880b93447c8 R14: ffff8880b923fb80 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6e76307a8c CR3: 000000000e734000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2085 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2295 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2493 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+0xb5/0x250 mm/kfence/core.c:833 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244