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WARNING: kernel/rcu/tree_stall.h:1049 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049, CPU#0: syz.0.3193/20098
Modules linked in:
CPU: 0 UID: 0 PID: 20098 Comm: syz.0.3193 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049
Code: ff ff 48 c7 c7 20 95 48 9a be 04 00 00 00 e8 b3 92 85 00 4c 89 f7 b8 01 00 00 00 87 05 75 2d 9d 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 00 29 96 8e 74 47 48 c7 c0 c0 da 30 90 48 c1 e8
RSP: 0018:ffffc90000007d98 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff81ab679d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8e962900
RBP: ffffc90000007f18 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff34912a4 R12: 0000000000002904
R13: dffffc0000000000 R14: ffffffff8e962900 R15: dffffc0000000000
FS: 00007f2d8e6356c0(0000) GS:ffff888125290000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3421cff8 CR3: 0000000057e33000 CR4: 0000000000350ef0
Call Trace:
rcu_core+0x3fe/0x1070 kernel/rcu/tree.c:2864
handle_softirqs+0x22a/0x840 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfd4/0x13d0 kernel/smp.c:892
Code: 89 ee 83 e6 01 31 ff e8 7a 05 0c 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 25 01 0c 00 eb 37 f3 90 43 0f b6 04 2c <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 0a 01 0c 00 eb e5 44 89
RSP: 0018:ffffc900037bf9c0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff8880b863c148 RCX: 0000000000080000
RDX: ffffc90003c2a000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc900037bfb00 R08: ffffffff9030a7f7 R09: 1ffffffff20614fe
R10: dffffc0000000000 R11: fffffbfff20614ff R12: 1ffff110170e8169
R13: dffffc0000000000 R14: ffff8880b8740b48 R15: 0000000000000001
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
on_each_cpu include/linux/smp.h:72 [inline]
smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2773 [inline]
smp_text_poke_batch_finish+0x5f5/0x1160 arch/x86/kernel/alternative.c:2983
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
static_key_enable+0x1a/0x20 kernel/jump_label.c:223
__sched_core_enable kernel/sched/core.c:475 [inline]
sched_core_get+0xaf/0x170 kernel/sched/core.c:499
sched_core_alloc_cookie+0x71/0xa0 kernel/sched/core_sched.c:20
sched_core_share_pid+0x31a/0x7a0 kernel/sched/core_sched.c:187
__do_sys_prctl kernel/sys.c:2808 [inline]
__se_sys_prctl+0x89b/0x1980 kernel/sys.c:2534
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2d8d79cdd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2d8e635028 EFLAGS: 00000246 ORIG_RAX: 000000000000009d
RAX: ffffffffffffffda RBX: 00007f2d8da15fa0 RCX: 00007f2d8d79cdd9
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 000000000000003e
RBP: 00007f2d8d832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2d8da16038 R14: 00007f2d8da15fa0 R15: 00007fff68677788
----------------
Code disassembly (best guess):
0: 89 ee mov %ebp,%esi
2: 83 e6 01 and $0x1,%esi
5: 31 ff xor %edi,%edi
7: e8 7a 05 0c 00 call 0xc0586
c: 41 83 e5 01 and $0x1,%r13d
10: 49 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%r13
17: fc ff df
1a: 75 07 jne 0x23
1c: e8 25 01 0c 00 call 0xc0146
21: eb 37 jmp 0x5a
23: f3 90 pause
25: 43 0f b6 04 2c movzbl (%r12,%r13,1),%eax
* 2a: 84 c0 test %al,%al <-- trapping instruction
2c: 75 10 jne 0x3e
2e: 41 f7 06 01 00 00 00 testl $0x1,(%r14)
35: 74 1e je 0x55
37: e8 0a 01 0c 00 call 0xc0146
3c: eb e5 jmp 0x23
3e: 44 rex.R
3f: 89 .byte 0x89