GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 ticks this GP) idle=a684/1/0x4000000000000000 softirq=29239/29239 fqs=3 rcu: (detected by 1, t=10502 jiffies, g=26193, q=150 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9300 Comm: syz.4.1235 Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x90 kernel/kcov.c:313 Code: 10 48 89 74 0a 18 4c 89 44 0a 20 e9 15 d0 50 ff 66 2e 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 4c 8b 04 24 65 48 8b 14 25 40 d6 03 00 65 8b 05 20 65 RSP: 0018:ffffc90000007c68 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff888030aa8000 RDX: ffff888030aa8000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff89f6006b R09: fffff52000000f7c R10: dffffc0000000000 R11: fffff52000000f7c R12: 0000000000000002 R13: ffffffff89f5ffb0 R14: ffff88805ad2f340 R15: ffff888030aa8ad8 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c27c646 CR3: 000000000e738000 CR4: 0000000000350ef0 Call Trace: advance_sched+0xd8/0xca0 net/sched/sch_taprio.c:925 __run_hrtimer kernel/time/hrtimer.c:1738 [inline] __hrtimer_run_queues+0x59d/0xd30 kernel/time/hrtimer.c:1802 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1864 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x112/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5855 Code: 2b 00 74 08 4c 89 f7 e8 3a 2b 8b 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90003def080 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920007bde1c RCX: ffff888030aa8ae8 RDX: dffffc0000000000 RSI: ffffffff8c0aa220 RDI: ffffffff8c603c60 RBP: ffffc90003def1d0 R08: ffffffff942fb847 R09: 1ffffffff285f708 R10: dffffc0000000000 R11: fffffbfff285f709 R12: 1ffff920007bde18 R13: dffffc0000000000 R14: ffffc90003def0e0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock_sched include/linux/rcupdate.h:941 [inline] pfn_valid+0x113/0x450 include/linux/mmzone.h:2067 page_table_check_clear+0x1e/0x550 mm/page_table_check.c:70 get_and_clear_full_ptes include/linux/pgtable.h:712 [inline] zap_present_folio_ptes mm/memory.c:1511 [inline] zap_present_ptes mm/memory.c:1596 [inline] do_zap_pte_range mm/memory.c:1698 [inline] zap_pte_range mm/memory.c:1740 [inline] zap_pmd_range mm/memory.c:1823 [inline] zap_pud_range mm/memory.c:1852 [inline] zap_p4d_range mm/memory.c:1873 [inline] unmap_page_range+0x376d/0x48d0 mm/memory.c:1894 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1984 exit_mmap+0x283/0xd40 mm/mmap.c:1284 __mmput+0x115/0x420 kernel/fork.c:1345 exit_mm+0x220/0x310 kernel/exit.c:570 do_exit+0x9ad/0x28e0 kernel/exit.c:925 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x16b2/0x1750 kernel/signal.c:3036 arch_do_signal_or_restart+0x96/0x860 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+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa74f58cda9 Code: Unable to access opcode bytes at 0x7fa74f58cd7f. RSP: 002b:00007fa7504770e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007fa74f7a5fa8 RCX: 00007fa74f58cda9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fa74f7a5fac RBP: 00007fa74f7a5fa0 R08: 7fffffffffffffff R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 00007fa74f7a5fac R13: 0000000000000000 R14: 00007ffe33b36e00 R15: 00007ffe33b36ee8 rcu: rcu_preempt kthread starved for 10496 jiffies! g26193 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:26104 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7ab/0x920 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148 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: 46 Comm: kworker/1:1 Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: events jump_label_update_timeout RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline] RIP: 0010:smp_call_function_many_cond+0x1bae/0x2d30 kernel/smp.c:885 Code: 89 e6 83 e6 01 31 ff e8 a0 e8 0b 00 41 83 e4 01 4c 8b 64 24 68 75 07 e8 50 e4 0b 00 eb 41 f3 90 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 03 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 2b e4 0b RSP: 0018:ffffc90000b67740 EFLAGS: 00000293 RAX: dffffc0000000000 RBX: 1ffff110170c8c91 RCX: ffff888020e85a00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90000b67940 R08: ffffffff81b38870 R09: 1ffffffff285f708 R10: dffffc0000000000 R11: fffffbfff285f709 R12: ffff8880b873fb08 R13: ffff8880b8646488 R14: ffff8880b873fb00 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2aeaf1 CR3: 000000000e738000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2114 [inline] text_poke_bp_batch+0x352/0xb30 arch/x86/kernel/alternative.c:2324 text_poke_flush arch/x86/kernel/alternative.c:2515 [inline] text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2522 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 __static_key_slow_dec_cpuslocked+0xc4/0x110 kernel/jump_label.c:315 __static_key_slow_dec kernel/jump_label.c:321 [inline] jump_label_update_timeout+0x1e/0x30 kernel/jump_label.c:329 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7ab/0x920 kernel/kthread.c:464 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244