rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=e714/1/0x4000000000000000 softirq=86403/86406 fqs=86
rcu: 	(detected by 0, t=10502 jiffies, g=64485, q=132 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 16358 Comm: syz.1.2631 Not tainted 6.15.0-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x5c/0xc0 kernel/rcu/tree.c:736
Code: 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 5c 48 03 1c ed 20 0d cf 8d 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <0f> b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 24 8b
RSP: 0018:ffffc90000a08e28 EFLAGS: 00000806
RAX: dffffc0000000000 RBX: ffff8880b8532de8 RCX: ffffffff81a87276
RDX: 1ffff110170a65bd RSI: ffffffff8bf4a420 RDI: ffffffff8dcf0d28
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880b8527840
R13: 0000000000000001 R14: ffff88804e697340 R15: 0000000000000001
FS:  00007f2d12dd56c0(0000) GS:ffff888124ada000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000025030 CR3: 000000005fcf7000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 trace_hrtimer_expire_exit include/trace/events/timer.h:306 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1764 [inline]
 __hrtimer_run_queues+0x7fe/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 b6 43 28 f6 48 89 df e8 5e 97 28 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 b5 03 19 f6 65 8b 05 fe 83 34 08 85 c0 74 16 5b
RSP: 0018:ffffc9000dc77818 EFLAGS: 00000246
RAX: 0000000000000006 RBX: ffff8880299a61c0 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffffffff8dbe444d RDI: ffffffff8bf4a4a0
RBP: 0000000000000286 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff90853117 R11: 0000000000000000 R12: 0000000000000002
R13: ffff8880299a6030 R14: ffff8880299a6200 R15: ffff8880299a5ba8
 __unix_dgram_recvmsg+0x326/0xee0 net/unix/af_unix.c:2447
 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2522
 sock_recvmsg_nosec net/socket.c:1017 [inline]
 ____sys_recvmsg+0x5f9/0x6b0 net/socket.c:2784
 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2828
 do_recvmmsg+0x2fe/0x740 net/socket.c:2923
 __sys_recvmmsg net/socket.c:2997 [inline]
 __do_sys_recvmmsg net/socket.c:3020 [inline]
 __se_sys_recvmmsg net/socket.c:3013 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3013
 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: 0033:0x7f2d14f8e969
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:00007f2d12dd5038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f2d151b6080 RCX: 00007f2d14f8e969
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f2d15010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f2d151b6080 R15: 00007ffdfde060d8
 </TASK>
rcu: rcu_preempt kthread starved for 10330 jiffies! g64485 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:27304 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: 13439 Comm: syz-executor Not tainted 6.15.0-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0x4af/0x1290 kernel/smp.c:885
Code: 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 7d 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 ff 83 e0 01 41 89 c5 89 c6 e8
RSP: 0000:ffffc9001cecf968 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffff8880b853f740 RCX: ffffffff81af2e99
RDX: ffff88807f422440 RSI: ffffffff81af2e73 RDI: 0000000000000005
RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffed10170a7ee9
R13: 0000000000000001 R14: dffffc0000000000 R15: ffff8880b843b040
FS:  00005555925d5500(0000) GS:ffff8881249da000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555925f05c8 CR3: 000000006a2a9000 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
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1291 [inline]
 flush_tlb_mm_range+0x322/0x1780 arch/x86/mm/tlb.c:1381
 flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
 ptep_clear_flush+0x136/0x180 mm/pgtable-generic.c:101
 wp_page_copy mm/memory.c:3544 [inline]
 do_wp_page+0x17cb/0x5930 mm/memory.c:3939
 handle_pte_fault mm/memory.c:6013 [inline]
 __handle_mm_fault+0x1ada/0x2a40 mm/memory.c:6140
 handle_mm_fault+0x3fe/0xad0 mm/memory.c:6309
 do_user_addr_fault+0x60c/0x1370 arch/x86/mm/fault.c:1337
 handle_page_fault arch/x86/mm/fault.c:1480 [inline]
 exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7fb9acd4cdbf
Code: 8d 34 19 48 39 d5 48 89 75 60 0f 95 c2 48 29 d8 48 83 c1 10 0f b6 d2 48 83 c8 01 48 c1 e2 02 48 09 da 48 83 ca 01 48 89 51 f8 <48> 89 46 08 eb 80 48 8d 0d 01 d1 0e 00 48 8d 15 05 e3 0e 00 bf 01
RSP: 002b:00007ffc27414210 EFLAGS: 00010206
RAX: 0000000000018a41 RBX: 0000000000008040 RCX: 00005555925e8590
RDX: 0000000000008041 RSI: 00005555925f05c0 RDI: 0000000000000004
RBP: 00007fb9acf83ca0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000802 R12: 0000000000008030
R13: 0000000000000076 R14: 00007fb9acf83d00 R15: 0000000000000000
 </TASK>
vkms_vblank_simulate: vblank timer overrun