rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (4 ticks this GP) idle=f034/1/0x4000000000000000 softirq=45526/45526 fqs=1 rcu: (detected by 0, t=10502 jiffies, g=41761, q=109 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 11836 Comm: syz.6.1477 Not tainted 6.13.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__this_cpu_preempt_check+0x0/0x20 lib/smp_processor_id.c:65 Code: c6 a0 ec d1 8b 48 c7 c7 e0 ec d1 8b e9 f9 fe ff ff 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 89 fe 48 c7 c7 20 ed d1 8b e9 cd fe ff ff 66 2e 0f RSP: 0018:ffffc90000a18c90 EFLAGS: 00000082 RAX: 0000000000000001 RBX: 1ffff92000143194 RCX: 00000000d439196c RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff8b6cdc40 RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff2dca398 R10: ffffffff96e51cc7 R11: 0000000000000004 R12: 0000000000000000 R13: ffffffff8e1bb900 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9ef2bfef98 CR3: 000000003052c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline] lock_acquire.part.0+0x12b/0x380 kernel/locking/lockdep.c:5851 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] advance_sched+0x67f/0xc60 net/sched/sch_taprio.c:985 __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:kasan_check_range+0x158/0x1a0 mm/kasan/generic.c:190 Code: 74 11 80 38 00 74 ef 4d 8d 1c 2c 48 85 c0 48 89 c2 75 93 48 89 da 4c 89 d8 4c 29 da e9 2c ff ff ff 5b b8 01 00 00 00 5d 41 5c cc cc cc cc b8 01 00 00 00 c3 cc cc cc cc 48 29 c3 48 89 da 49 RSP: 0018:ffffc9000fab7588 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffff88801da75eb8 RCX: ffffffff82086866 RDX: ffffed1003b4ebd8 RSI: 0000000000000004 RDI: ffff88801da75eb8 RBP: ffff88801da75e70 R08: 0000000000000000 R09: ffffed1003b4ebd7 R10: ffff88801da75ebb R11: 0000000000000003 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000000 R15: dffffc0000000000 instrument_atomic_read include/linux/instrumented.h:68 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] page_table_check_clear.part.0+0x316/0x540 mm/page_table_check.c:89 page_table_check_clear mm/page_table_check.c:70 [inline] __page_table_check_pte_clear+0x328/0x580 mm/page_table_check.c:169 page_table_check_pte_clear include/linux/page_table_check.h:49 [inline] ptep_get_and_clear_full arch/x86/include/asm/pgtable.h:1337 [inline] get_and_clear_full_ptes include/linux/pgtable.h:705 [inline] zap_present_folio_ptes mm/memory.c:1502 [inline] zap_present_ptes mm/memory.c:1585 [inline] zap_pte_range mm/memory.c:1627 [inline] zap_pmd_range mm/memory.c:1753 [inline] zap_pud_range mm/memory.c:1782 [inline] zap_p4d_range mm/memory.c:1803 [inline] unmap_page_range+0x22f6/0x3d10 mm/memory.c:1824 unmap_single_vma+0x194/0x2b0 mm/memory.c:1870 unmap_vmas+0x22f/0x490 mm/memory.c:1914 exit_mmap+0x1c6/0xb20 mm/mmap.c:1668 __mmput+0x12a/0x4c0 kernel/fork.c:1348 mmput+0x62/0x70 kernel/fork.c:1370 exit_mm kernel/exit.c:570 [inline] do_exit+0x9ba/0x2d70 kernel/exit.c:925 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x24ed/0x26c0 kernel/signal.c:3017 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [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+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9ef1d85d29 Code: Unable to access opcode bytes at 0x7f9ef1d85cff. RSP: 002b:00007f9ef2c200e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f9ef1f75fa8 RCX: 00007f9ef1d85d29 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f9ef1f75fa8 RBP: 00007f9ef1f75fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9ef1f75fac R13: 0000000000000000 R14: 00007fff237e2dd0 R15: 00007fff237e2eb8 rcu: rcu_preempt kthread starved for 10497 jiffies! g41761 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: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: 0 UID: 0 PID: 12 Comm: kworker/u8:1 Not tainted 6.13.0-rc4-syzkaller #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+0x45d/0x1300 kernel/smp.c:884 Code: 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 ba 0e 0c 00 f3 90 41 0f b6 04 24 <40> 38 c5 7c 08 84 c0 0f 85 a7 0c 00 00 8b 43 08 31 ff 83 e0 01 41 RSP: 0018:ffffc90000117998 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b8744a40 RCX: ffffffff818e071c RDX: ffff88801cef4880 RSI: ffffffff818e06f6 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000006 R12: ffffed10170e8949 R13: 0000000000000001 R14: ffff8880b8744a48 R15: ffff8880b863fe40 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd874657d58 CR3: 000000000df7e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 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:2114 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_flush arch/x86/kernel/alternative.c:2512 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2522 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