GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=0fbc/1/0x4000000000000000 softirq=42120/42120 fqs=0
rcu: 	(detected by 0, t=10502 jiffies, g=33161, q=272 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 10784 Comm: syz.3.1253 Not tainted 6.15.0-rc4-syzkaller-00296-ge8ab83e34bdc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x41/0xc0 kernel/rcu/tree.c:736
Code: a5 93 89 c5 83 f8 07 0f 87 82 00 00 00 48 8d 3c ed 00 cd ce 8d 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <75> 5c 48 03 1c ed 00 cd ce 8d 48 b8 00 00 00 00 00 fc ff df 48 89
RSP: 0018:ffffc90000a08d78 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffffffff93a53de8 RCX: ffffffff89817f89
RDX: 1ffffffff1b9d9a1 RSI: ffffffff8bf48260 RDI: ffffffff8dcecd08
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 184a1063fe84177b
R13: 184a1063fe84177b R14: 0000000000000002 R15: ffff88805cec9810
FS:  00007fe7690316c0(0000) GS:ffff888124adf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2d288d CR3: 000000005cd03000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_read_lock include/linux/rcupdate.h:842 [inline]
 advance_sched+0x93c/0xc80 net/sched/sch_taprio.c:985
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 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
 </IRQ>
 <TASK>
 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 e6 9e 28 f6 48 89 df e8 8e f2 28 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 e5 5e 19 f6 65 8b 05 1e a4 34 08 85 c0 74 16 5b
RSP: 0018:ffffc9000c66f3a8 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff888029edb098 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffffffff8dbe1239 RDI: ffffffff8bf482e0
RBP: 0000000000000286 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90850517 R11: 0000000000000000 R12: 000000000000001f
R13: dffffc0000000000 R14: ffff8880b8532eb0 R15: ffff8880b8532fb0
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1526 [inline]
 folio_batch_move_lru+0x2b4/0x3b0 mm/swap.c:174
 __folio_batch_add_and_move+0x369/0xc90 mm/swap.c:196
 shmem_alloc_and_add_folio+0x83b/0xc20 mm/shmem.c:1952
 shmem_get_folio_gfp+0x687/0x1530 mm/shmem.c:2533
 shmem_fault+0x1fe/0xa30 mm/shmem.c:2734
 __do_fault+0x10a/0x490 mm/memory.c:5098
 do_read_fault mm/memory.c:5518 [inline]
 do_fault mm/memory.c:5652 [inline]
 do_pte_missing+0x1031/0x3fb0 mm/memory.c:4160
 handle_pte_fault mm/memory.c:5997 [inline]
 __handle_mm_fault+0x103d/0x2a40 mm/memory.c:6140
 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309
 faultin_page mm/gup.c:1193 [inline]
 __get_user_pages+0x771/0x36f0 mm/gup.c:1491
 populate_vma_page_range+0x278/0x3a0 mm/gup.c:1929
 __mm_populate+0x1d8/0x380 mm/gup.c:2032
 mm_populate include/linux/mm.h:3487 [inline]
 vm_mmap_pgoff+0x362/0x450 mm/util.c:584
 ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:607
 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
 __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
 __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe76818e969
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:00007fe769031038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fe7683b5fa0 RCX: 00007fe76818e969
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007fe768210ab1 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe7683b5fa0 R15: 00007fff01867cf8
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g33161 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:27192 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x116f/0x5de0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6860
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 10786 Comm: syz.2.1252 Not tainted 6.15.0-rc4-syzkaller-00296-ge8ab83e34bdc #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4a5/0x1290 kernel/smp.c:885
Code: 89 ee e8 be 12 0c 00 85 ed 74 48 48 8b 44 24 20 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 f4 83 c5 03 e8 5d 17 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 de 0b 00 00 8b 43 08 31
RSP: 0018:ffffc9000c2f7720 EFLAGS: 00000246
RAX: 0000000000080000 RBX: ffff8880b853f740 RCX: ffffc9000c721000
RDX: 0000000000080000 RSI: ffffffff81af1b93 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170a7ee9
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b843b040
FS:  00007f4746e3b6c0(0000) GS:ffff8881249df000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3f0c76 CR3: 000000003364e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1052
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:2455 [inline]
 text_poke_bp_batch+0x220/0x760 arch/x86/kernel/alternative.c:2665
 text_poke_flush arch/x86/kernel/alternative.c:2856 [inline]
 text_poke_flush arch/x86/kernel/alternative.c:2853 [inline]
 text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2863
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 jump_label_update+0x376/0x550 kernel/jump_label.c:919
 static_key_slow_inc_cpuslocked kernel/jump_label.c:168 [inline]
 static_key_slow_inc_cpuslocked+0x82/0x120 kernel/jump_label.c:151
 static_key_slow_inc+0x1a/0x30 kernel/jump_label.c:191
 kvm_create_lapic+0x37b/0x4d0 arch/x86/kvm/lapic.c:2894
 kvm_arch_vcpu_create+0x27a/0xac0 arch/x86/kvm/x86.c:12290
 kvm_vm_ioctl_create_vcpu virt/kvm/kvm_main.c:4124 [inline]
 kvm_vm_ioctl+0xf25/0x3d40 virt/kvm/kvm_main.c:5070
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl fs/ioctl.c:892 [inline]
 __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4745f8e969
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:00007f4746e3b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f47461b5fa0 RCX: 00007f4745f8e969
RDX: 0000000000000002 RSI: 000000000000ae41 RDI: 0000000000000008
RBP: 00007f4746010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f47461b5fa0 R15: 00007fff8c4f27e8
 </TASK>
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog