rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=33dc/0/0x1 softirq=390085/390085 fqs=5
rcu: 	(detected by 1, t=10503 jiffies, g=336117, q=23324 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:rb_link_node include/linux/rbtree.h:98 [inline]
RIP: 0010:__rb_add include/linux/rbtree.h:238 [inline]
RIP: 0010:rb_add_linked include/linux/rbtree.h:281 [inline]
RIP: 0010:timerqueue_linked_add+0x24a/0x2e0 lib/timerqueue.c:96
Code: 00 74 08 4c 89 ef e8 a5 7b 57 f6 4d 89 75 00 49 8d 7d 08 ba 10 00 00 00 31 f6 e8 71 7d 57 f6 4c 89 f8 48 c1 e8 03 80 3c 28 00 <74> 08 4c 89 ff e8 7c 7b 57 f6 4d 89 2f 4c 89 ef 48 89 de e8 8e 64
RSP: 0018:ffffc90000007d40 EFLAGS: 00000046
RAX: 1ffff110170c50a3 RBX: ffff8880b8628518 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880299c2318
RBP: dffffc0000000000 R08: ffff8880299c2317 R09: 0000000000000000
R10: ffff8880299c2308 R11: ffffed1005338463 R12: 1ffff110170c5098
R13: ffff8880299c2300 R14: 0000000000000000 R15: ffff8880b8628518
FS:  0000000000000000(0000) GS:ffff888124cd8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000012c0 CR3: 0000000074d10000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 enqueue_hrtimer+0x18e/0x2c0 kernel/time/hrtimer.c:1144
 __run_hrtimer kernel/time/hrtimer.c:2083 [inline]
 __hrtimer_run_queues+0x4ce/0xa10 kernel/time/hrtimer.c:2124
 hrtimer_interrupt+0x4cd/0xaa0 kernel/time/hrtimer.c:2243
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 2c 90 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d d3 40 25 00 fb f4 <e9> cc 07 03 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8ea07ca0 EFLAGS: 00000242
RAX: 00000000013ed2d9 RBX: ffffffff819ba090 RCX: 8000000000000001
RDX: 0000000000000001 RSI: ffffffff8e474cae RDI: ffffffff8c6d9480
RBP: ffffffff8ea07d78 R08: ffff8880b8633a1b R09: 1ffff110170c6743
R10: dffffc0000000000 R11: ffffed10170c6744 R12: 0000000000000000
R13: 1ffffffff1d51df0 R14: 1ffffffff1d40f9c R15: dffffc0000000000
 arch_safe_halt arch/x86/kernel/process.c:767 [inline]
 default_idle+0x9/0x20 arch/x86/kernel/process.c:768
 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x2e0/0x540 kernel/sched/idle.c:355
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:454
 rest_init+0x378/0x3a0 init/main.c:727
 start_kernel+0x392/0x3e0 init/main.c:1185
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x137/0x1b0 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x157
 </TASK>
rcu: rcu_preempt kthread starved for 9636 jiffies! g336117 f0x2 RCU_GP_WAIT_FQS(5) ->state=R ->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:27744 pid:17    tgid:17    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5520 [inline]
 __schedule+0x17db/0x58f0 kernel/sched/core.c:7270
 __schedule_loop kernel/sched/core.c:7347 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7362
 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
 kthread+0x38b/0x480 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 29778 Comm: iou-sqp-29775 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x75/0x80 kernel/kcov.c:231
Code: 10 17 00 00 83 fa 02 75 21 48 8b 91 18 17 00 00 48 8b 32 48 8d 7e 01 8b 89 14 17 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 <e9> 06 8d 1f 0a cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000489f1d8 EFLAGS: 00000293
RAX: ffffffff81bb6bfe RBX: ffff8880b8643708 RCX: ffff88802e2bbe80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000489f330 R08: ffff88802e2bd41f R09: 1ffff11005c57a83
R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff110170c86e1
R13: 0000000000000000 R14: ffff8880b8643700 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888124dd8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fee296a68d0 CR3: 00000000778f8000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 csd_lock_wait kernel/smp.c:363 [inline]
 csd_lock kernel/smp.c:396 [inline]
 smp_call_function_many_cond+0x63e/0x1500 kernel/smp.c:944
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
 flush_tlb_mm_range+0x8ff/0x1090 arch/x86/mm/tlb.c:1435
 tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
 tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:509 [inline]
 tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:423
 tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:549
 free_ldt_pgtables+0x192/0x360 arch/x86/kernel/ldt.c:411
 arch_exit_mmap arch/x86/include/asm/mmu_context.h:229 [inline]
 exit_mmap+0x1bf/0x9f0 mm/mmap.c:1300
 __mmput+0x118/0x420 kernel/fork.c:1193
 exit_mm+0x221/0x2d0 kernel/exit.c:614
 do_exit+0x6cd/0x2360 kernel/exit.c:996
 io_sq_thread+0x1bd0/0x1e50 io_uring/sqpoll.c:421
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>