rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P61/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=36937, q=1164 ncpus=2)
task:kworker/u8:4    state:R  running task     stack:21248 pid:61    tgid:61    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: iou_exit io_ring_exit_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x14bc/0x5000 kernel/sched/core.c:6863
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190
 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__asan_memset+0x22/0x50 mm/kasan/shadow.c:84
Code: 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 7e e4 ff ff <84> c0 74 11 4c 89 f7 89 ee 48 89 da 5b 41 5e 5d e9 29 0c 34 09 31
RSP: 0018:ffffc9000212f318 EFLAGS: 00000256
RAX: ffffc9000212f801 RBX: 0000000000000010 RCX: ffffffff81744d8e
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc9000212f458
RBP: 0000000000000000 R08: ffffc9000212f467 R09: 1ffff92000425e8c
R10: dffffc0000000000 R11: fffff52000425e8d R12: ffffc9000212f458
R13: 1ffff92000425e83 R14: ffffc9000212f458 R15: ffffc9000212f450
 unwind_next_frame+0xeae/0x23d0 arch/x86/kernel/unwind_orc.c:607
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5776
 kmalloc_noprof include/linux/slab.h:957 [inline]
 slab_free_hook mm/slub.c:2492 [inline]
 slab_free mm/slub.c:6670 [inline]
 kmem_cache_free+0x16b/0x620 mm/slub.c:6781
 __io_req_caches_free+0x1c1/0x270 io_uring/io_uring.c:2826
 io_req_caches_free+0x21/0x60 io_uring/io_uring.c:2838
 io_ring_exit_work+0x3b3/0x8d0 io_uring/io_uring.c:3024
 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3279
 process_scheduled_works kernel/workqueue.c:3362 [inline]
 worker_thread+0x9b0/0xee0 kernel/workqueue.c:3443
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: rcu_preempt kthread starved for 10542 jiffies! g36937 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:27344 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x14bc/0x5000 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6960
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 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 13 50 0c 00 f3 0f 1e fa fb f4 <e9> c8 ed 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0000:ffffc90000197de0 EFLAGS: 000002c6
RAX: 513ef0369f1aa800 RBX: ffffffff8197983a RCX: 513ef0369f1aa800
RDX: 0000000000000001 RSI: ffffffff8d7939c1 RDI: ffffffff8bc08360
RBP: ffffc90000197f10 R08: ffff8880b87336db R09: 1ffff110170e66db
R10: dffffc0000000000 R11: ffffed10170e66dc R12: ffffffff8f822a70
R13: 1ffff110039dcb70 R14: 0000000000000001 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff888125f31000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffe70 CR3: 000000000dd3a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:767
 default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:191 [inline]
 do_idle+0x1ea/0x520 kernel/sched/idle.c:332
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147
 </TASK>