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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#1: syz.3.1577/13720
Modules linked in:
CPU: 1 UID: 0 PID: 13720 Comm: syz.3.1577 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:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049
Code: ff ff 48 c7 c7 a0 85 8f 99 be 04 00 00 00 e8 03 90 7f 00 4c 89 f7 b8 01 00 00 00 87 05 25 f8 e7 17 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 80 6e f4 8d 74 47 48 c7 c0 a0 54 82 8f 48 c1 e8
RSP: 0018:ffffc90000a08d98 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000246 RCX: ffffffff81a78d6d
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8df46e80
RBP: ffffc90000a08f30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff331f0b4 R12: 0000000000002904
R13: 1ffff110170e771a R14: ffffffff8df46e80 R15: dffffc0000000000
FS: 00007fe16bbfa6c0(0000) GS:ffff888125f1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000001f8030 CR3: 0000000048864000 CR4: 0000000000350ef0
Call Trace:
rcu_core+0x5f5/0x1720 kernel/rcu/tree.c:2852
handle_softirqs+0x22b/0x7c0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x60/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x222/0x340 kernel/locking/lockdep.c:5872
Code: ff ff ff e8 e0 d0 bb 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 ca 1f e2 10 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 9a 50 72 ff cc 48 8d 3d f7 78 e7
RSP: 0018:ffffc9000dc6fb70 EFLAGS: 00000282
RAX: c6b89a941200ba00 RBX: 0000000000000000 RCX: 0000000000000046
RDX: 000000009c930800 RSI: ffffffff8d976a7d RDI: ffffffff8bc08660
RBP: ffffffff820e8490 R08: ffffffff820e8490 R09: ffff888076c94cc0
R10: dffffc0000000000 R11: fffff52001b8dfc2 R12: 0000000000000001
R13: ffff888076c94cc0 R14: 0000000000000001 R15: 0000000000000246
__might_fault+0xcc/0x130 mm/memory.c:7174
__clear_user arch/x86/include/asm/uaccess_64.h:181 [inline]
clear_user arch/x86/include/asm/uaccess_64.h:205 [inline]
copy_siginfo_to_user+0x80/0xc0 kernel/signal.c:3503
x64_setup_rt_frame+0x776/0xd40 arch/x86/kernel/signal_64.c:194
setup_rt_frame arch/x86/kernel/signal.c:250 [inline]
handle_signal arch/x86/kernel/signal.c:294 [inline]
arch_do_signal_or_restart+0x3d1/0x7a0 arch/x86/kernel/signal.c:339
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop+0x87/0x4e0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe16ad8f747
Code: ff ff 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
RSP: 002b:00007fe16bbfa0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 00000000000000ca RBX: 00007fe16afe5fa8 RCX: 00007fe16ad8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fe16afe5fa8
RBP: 00007fe16afe5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe16afe6038 R14: 00007ffe46748510 R15: 00007ffe467485f8
----------------
Code disassembly (best guess), 3 bytes skipped:
0: e8 e0 d0 bb 09 call 0x9bbd0e5
5: f7 44 24 08 00 02 00 testl $0x200,0x8(%rsp)
c: 00
d: 0f 84 3a ff ff ff je 0xffffff4d
13: 65 48 8b 05 ca 1f e2 mov %gs:0x10e21fca(%rip),%rax # 0x10e21fe5
1a: 10
1b: 48 3b 44 24 58 cmp 0x58(%rsp),%rax
20: 75 33 jne 0x55
22: fb sti
23: 48 83 c4 60 add $0x60,%rsp
* 27: 5b pop %rbx <-- trapping instruction
28: 41 5c pop %r12
2a: 41 5d pop %r13
2c: 41 5e pop %r14
2e: 41 5f pop %r15
30: 5d pop %rbp
31: e9 9a 50 72 ff jmp 0xff7250d0
36: cc int3
37: 48 rex.W
38: 8d .byte 0x8d
39: 3d .byte 0x3d
3a: f7 78 e7 idivl -0x19(%rax)