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1
WARNING: kernel/rcu/tree_stall.h:1063 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1063, CPU#0: rcuc/0/20
Modules linked in:
CPU: 0 UID: 0 PID: 20 Comm: rcuc/0 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1063
Code: ff ff 48 c7 c7 a0 56 b3 99 be 04 00 00 00 e8 73 ee 86 00 4c 89 f7 b8 01 00 00 00 87 05 75 6f 07 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff c0 97 1c 8e 74 47 48 c7 c0 c0 3d b2 8f 48 c1 e8
RSP: 0018:ffffc90000197b98 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff81abe71d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8e1c97c0
RBP: ffffc90000197d78 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff3366ad4 R12: 0000000000002904
R13: ffffffff81acdac7 R14: ffffffff8e1c97c0 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888125bc2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055fe71673a38 CR3: 0000000037d60000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 rcu_core kernel/rcu/tree.c:2914 [inline]
 rcu_cpu_kthread+0x7b4/0x1740 kernel/rcu/tree.c:3007
 smpboot_thread_fn+0x565/0xa70 kernel/smpboot.c:160
 kthread+0x38b/0x470 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>