rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P296/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=46637, q=481 ncpus=2)
task:kworker/u8:6    state:R  running task     stack:23544 pid:296   tgid:296   ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: kvfree_rcu_reclaim kfree_rcu_monitor
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0xb59/0x20b0 arch/x86/kernel/unwind_orc.c:598
Code: 3d 75 30 00 e9 c0 f7 ff ff e8 53 ff bb 00 e9 f4 f4 ff ff 4c 89 f7 e8 e6 fe bb 00 e9 19 f6 ff ff e8 0c ff bb 00 e9 d6 f5 ff ff <49> 8d 76 f8 ba 08 00 00 00 4d 8d 7d 34 4c 89 ef 4c 89 44 24 28 48
RSP: 0018:ffffc90003157630 EFLAGS: 00000246
RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff912fbd62
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffc900031576e8 R08: ffffffff912fbd66 R09: 000000001a54d674
R10: 0000000000000002 R11: 000000000001288a R12: ffffc900031576f0
R13: ffffc900031576a0 R14: ffffc90003157a00 R15: ffffc900031579f0
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2540 [inline]
 slab_free_freelist_hook mm/slub.c:2569 [inline]
 slab_free_bulk mm/slub.c:6703 [inline]
 kmem_cache_free_bulk mm/slub.c:7390 [inline]
 kmem_cache_free_bulk+0x2bf/0x680 mm/slub.c:7369
 kfree_bulk include/linux/slab.h:830 [inline]
 kvfree_rcu_bulk+0x1b7/0x1e0 mm/slab_common.c:1523
 kvfree_rcu_drain_ready mm/slab_common.c:1728 [inline]
 kfree_rcu_monitor+0x1d0/0x2f0 mm/slab_common.c:1801
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
 process_scheduled_works kernel/workqueue.c:3340 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g46637 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=24212
rcu: rcu_preempt kthread starved for 10502 jiffies! g46637 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28440 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6960
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13911 Comm: syz.2.1541 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:preempt_count_sub+0x0/0x160 kernel/sched/core.c:5746
Code: 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 c7 c7 60 5c b9 93 e9 a0 ee 6b 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 c7 c0 80 32 c2 9a 53 89 fb 48 ba 00 00 00 00 00 fc
RSP: 0018:ffffc90000007d30 EFLAGS: 00000046
RAX: 0000000000000046 RBX: ffffffff9ae77b48 RCX: ffffffff819a47b3
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: 0000000000000001
RBP: 0000000000000002 R08: 0000000000000000 R09: fffffbfff35cef69
R10: ffffffff9ae77b4b R11: ffff8880285454b0 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff888054efc300 R15: 1ffff92000000fac
FS:  00007fc835f926c0(0000) GS:ffff8881248f5000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000033f030 CR3: 000000004a85c000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x3b/0x80 kernel/locking/spinlock.c:194
 debug_object_deactivate+0x1ec/0x3a0 lib/debugobjects.c:888
 debug_hrtimer_deactivate kernel/time/hrtimer.c:443 [inline]
 debug_deactivate kernel/time/hrtimer.c:483 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1745 [inline]
 __hrtimer_run_queues+0x46f/0xc40 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
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 c6 0d 1f f6 48 89 df e8 7e 60 1f f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 <bf> 01 00 00 00 e8 85 63 0f f6 65 8b 05 2e c9 37 08 85 c0 74 16 5b
RSP: 0018:ffffc9001b8e7760 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff888069a75880 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffffffff8dacdf23 RDI: ffffffff8bf2b400
RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff9088b4d7 R11: ffff8880285454b0 R12: ffff88801eb87640
R13: 0000000000000246 R14: ffff888069a75868 R15: ffffc9001b8e78e8
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __skb_try_recv_datagram+0x172/0x4f0 net/core/datagram.c:267
 __unix_dgram_recvmsg+0x1bc/0xc30 net/unix/af_unix.c:2576
 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2675
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 ____sys_recvmsg+0x5f9/0x6b0 net/socket.c:2810
 ___sys_recvmsg+0x114/0x1a0 net/socket.c:2854
 do_recvmmsg+0x2fe/0x750 net/socket.c:2949
 __sys_recvmmsg net/socket.c:3023 [inline]
 __do_sys_recvmmsg net/socket.c:3046 [inline]
 __se_sys_recvmmsg net/socket.c:3039 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3039
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc83518f749
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:00007fc835f92038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fc8353e6090 RCX: 00007fc83518f749
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007fc835213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc8353e6128 R14: 00007fc8353e6090 R15: 00007ffc37f45878
 </TASK>