rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=d344/1/0x4000000000000000 softirq=82943/82944 fqs=2 rcu: (detected by 1, t=10506 jiffies, g=63177, q=415 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 24242 Comm: syz.1.8204 Not tainted 6.13.0-rc7-syzkaller-00043-g619f0b6fad52 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:__kasan_check_read+0x0/0x20 mm/kasan/shadow.c:30 Code: c3 cc cc cc cc 48 83 c4 60 48 c7 c7 98 88 7c 8d 5b 5d 41 5c e9 01 85 7c ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 0c 24 89 f6 31 d2 e9 1f f1 ff ff 66 66 2e 0f 1f RSP: 0018:ffffc90000007e08 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81874c8e RDX: ffff888060bc8000 RSI: 0000000000000008 RDI: ffffffff905f4990 RBP: ffff8880668fd340 R08: 0000000000000005 R09: 0000000000000007 R10: 0000000000000000 R11: 00000000000d1fba R12: ffff8880668fd340 R13: ffff8880b862cc00 R14: ffff8880b862ca00 R15: ffffffff8941a970 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020006680 CR3: 000000000df7e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:570 [inline] cpu_online include/linux/cpumask.h:1117 [inline] trace_hrtimer_cancel+0x57/0x220 include/trace/events/timer.h:317 debug_deactivate kernel/time/hrtimer.c:476 [inline] __run_hrtimer kernel/time/hrtimer.c:1707 [inline] __hrtimer_run_queues+0x484/0xae0 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:vma_has_recency include/linux/mm_inline.h:610 [inline] RIP: 0010:vma_has_recency include/linux/mm_inline.h:605 [inline] RIP: 0010:zap_present_folio_ptes mm/memory.c:1510 [inline] RIP: 0010:zap_present_ptes mm/memory.c:1585 [inline] RIP: 0010:zap_pte_range mm/memory.c:1627 [inline] RIP: 0010:zap_pmd_range mm/memory.c:1753 [inline] RIP: 0010:zap_pud_range mm/memory.c:1782 [inline] RIP: 0010:zap_p4d_range mm/memory.c:1803 [inline] RIP: 0010:unmap_page_range+0x145b/0x3d10 mm/memory.c:1824 Code: fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 44 28 00 00 45 8b 6d 48 31 ff 41 81 e5 00 00 80 00 44 89 ee 90 77 b6 ff 45 85 ed 75 0f e8 86 7c b6 ff 48 8b 7c 24 40 e8 dc RSP: 0018:ffffc900045ef668 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff81e3a794 RDX: 1ffff1100fe71ce9 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 8000000029b48027 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000005f89 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffffc900045efaa8 unmap_single_vma+0x194/0x2b0 mm/memory.c:1870 unmap_vmas+0x22f/0x490 mm/memory.c:1914 exit_mmap+0x1c6/0xb20 mm/mmap.c:1672 __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: 0033:0x7f5413185d29 Code: Unable to access opcode bytes at 0x7f5413185cff. RSP: 002b:00007f5413fa00e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f5413376088 RCX: 00007f5413185d29 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5413376088 RBP: 00007f5413376080 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f541337608c R13: 0000000000000000 R14: 00007ffca1558450 R15: 00007ffca1558538 rcu: rcu_preempt kthread starved for 10495 jiffies! g63177 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:28120 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: 61 Comm: kworker/u8:4 Not tainted 6.13.0-rc7-syzkaller-00043-g619f0b6fad52 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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 aa 0b 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 RSP: 0018:ffffc9000212f998 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b86469c0 RCX: ffffffff818e191c RDX: ffff88801bfba440 RSI: ffffffff818e18f6 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170c8d39 R13: 0000000000000001 R14: ffff8880b86469c8 R15: ffff8880b873fe40 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007efc9c977bac 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:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 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 vkms_vblank_simulate: vblank timer overrun