rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (3 ticks this GP) idle=098c/1/0x4000000000000000 softirq=89283/89283 fqs=3 rcu: (detected by 1, t=10505 jiffies, g=89869, q=341 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 23167 Comm: syz.5.4867 Not tainted 6.12.0-rc6-syzkaller-00099-g7758b206117d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] RIP: 0010:rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:737 Code: 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 53 65 ff 05 eb 59 90 7e e8 ce ea af 09 <48> c7 c3 28 81 03 00 83 f8 07 89 c5 0f 87 82 00 00 00 48 8d 3c ed RSP: 0018:ffffc90000007d38 EFLAGS: 00000086 RAX: 0000000000000000 RBX: 1ffff92000000fac RCX: ffffffff816a9cf9 RDX: fffffbfff20beb22 RSI: ffffffff8bd1b300 RDI: ffffffff8bd1b340 RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff20beb21 R10: ffffffff905f590f R11: 0000000000000000 R12: ffff8880b862c9d8 R13: ffff8880b862cac0 R14: 000000000003dbcc R15: ffffffff893256b0 FS: 00007fc96211f6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c39afca CR3: 0000000060d5a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x4f6/0x6f0 kernel/locking/lockdep.c:5836 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x1a/0x80 kernel/locking/spinlock.c:194 __run_hrtimer kernel/time/hrtimer.c:1687 [inline] __hrtimer_run_queues+0x53d/0xae0 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1817 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:__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 a6 c2 44 f6 48 89 df e8 be 3f 45 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 e5 48 36 f6 65 8b 05 f6 01 de 74 85 c0 74 16 5b RSP: 0018:ffffc900051ef3e8 EFLAGS: 00000246 RAX: 0000000000000006 RBX: ffff88803649a098 RCX: 1ffffffff2dca2e5 RDX: 0000000000000000 RSI: ffffffff8b6cd040 RDI: ffffffff8bd1b380 RBP: 0000000000000246 R08: 0000000000000001 R09: fffffbfff2dc5b93 R10: ffffffff96e2dc9f R11: 0000000000000000 R12: 000000000000001f R13: dffffc0000000000 R14: ffff8880b86381f0 R15: ffff8880b86382f0 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1565 [inline] folio_batch_move_lru+0x2b5/0x3b0 mm/swap.c:219 __folio_batch_add_and_move+0x35b/0xc60 mm/swap.c:241 shmem_alloc_and_add_folio+0x83b/0xc00 mm/shmem.c:1869 shmem_get_folio_gfp+0x689/0x1530 mm/shmem.c:2332 shmem_fault+0x200/0xae0 mm/shmem.c:2533 __do_fault+0x10a/0x490 mm/memory.c:4882 do_read_fault mm/memory.c:5297 [inline] do_fault mm/memory.c:5431 [inline] do_pte_missing+0xec5/0x3e70 mm/memory.c:3965 handle_pte_fault mm/memory.c:5766 [inline] __handle_mm_fault+0x100a/0x2a10 mm/memory.c:5909 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6077 faultin_page mm/gup.c:1187 [inline] __get_user_pages+0x8d9/0x3b50 mm/gup.c:1485 populate_vma_page_range+0x27f/0x3a0 mm/gup.c:1923 __mm_populate+0x1d6/0x380 mm/gup.c:2026 mm_populate include/linux/mm.h:3371 [inline] vm_mmap_pgoff+0x293/0x360 mm/util.c:593 ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:542 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:79 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:79 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc96137e719 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:00007fc96211f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fc961535f80 RCX: 00007fc96137e719 RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007fc9613f139e R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc961535f80 R15: 00007ffec185e558 rcu: rcu_preempt kthread starved for 10485 jiffies! g89869 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:27504 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0xe55/0x5740 kernel/sched/core.c:6690 __schedule_loop kernel/sched/core.c:6767 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6782 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2615 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: 17704 Comm: kworker/u8:8 Not tainted 6.12.0-rc6-syzkaller-00099-g7758b206117d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x458/0x1300 kernel/smp.c:884 Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 8a 1b 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 a4 0c 00 00 8b 43 08 31 RSP: 0018:ffffc90004bb7998 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b8646b80 RCX: ffffffff81815fec RDX: ffff88807c972440 RSI: ffffffff81815fc6 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170c8d71 R13: 0000000000000001 R14: ffff8880b8646b88 R15: ffff8880b8740100 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0332937a8c CR3: 000000000df7c000 CR4: 00000000003526f0 DR0: 0000000000000400 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1051 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2085 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2295 text_poke_flush arch/x86/kernel/alternative.c:2486 [inline] text_poke_flush arch/x86/kernel/alternative.c:2483 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2493 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:920 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate mm/kfence/core.c:849 [inline] toggle_allocation_gate+0xfc/0x260 mm/kfence/core.c:841 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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