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WARNING: CPU: 1 PID: 8735 at kernel/rcu/tree_stall.h:937 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:929
Modules linked in:
CPU: 1 PID: 8735 Comm: syz.0.1168 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:937
Code: ff ff ff 48 c7 c7 20 fc 31 96 be 04 00 00 00 e8 0a df 58 00 48 89 df b8 01 00 00 00 87 05 0c ad cc 14 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 00 2f 32 8c 74 47 48 c7 c0 04 17 8a 8d 48 c1 e8 03
RSP: 0018:ffffc90000dd0bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8c322f00 RCX: ffffffff81654f06
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8c322f00
RBP: ffffc90000dd0e10 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2c63f84 R12: 0000000000002904
R13: ffff8880b913b258 R14: 0000000000000a02 R15: dffffc0000000000
FS: 00007fbfef8286c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbfef7e5ff8 CR3: 0000000053931000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_core+0x62b/0x1670 kernel/rcu/tree.c:2758
handle_softirqs+0x339/0x830 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5671
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc9000352f978 EFLAGS: 00000206
RAX: d194bc17c0021200 RBX: ffff888078d19dc0 RCX: d194bc17c0021200
RDX: 0000000000000000 RSI: ffffffff8a2b3a20 RDI: ffffffff8a79f980
RBP: 0000000000000000 R08: ffff888078d19dc7 R09: 1ffff1100f1a33b8
R10: dffffc0000000000 R11: ffffed100f1a33b9 R12: dffffc0000000000
R13: 0000000000000246 R14: ffffffff8c31eb60 R15: 00000000ffffffff
lock_is_held include/linux/lockdep.h:287 [inline]
___might_sleep+0xea/0x610 kernel/sched/core.c:9624
__might_fault+0x6b/0x110 mm/memory.c:5354
__copy_to_user include/linux/uaccess.h:143 [inline]
save_xstate_epilog arch/x86/kernel/fpu/signal.c:104 [inline]
copy_fpstate_to_sigframe+0x8aa/0xbf0 arch/x86/kernel/fpu/signal.c:217
get_sigframe arch/x86/kernel/signal.c:295 [inline]
__setup_rt_frame arch/x86/kernel/signal.c:471 [inline]
setup_rt_frame arch/x86/kernel/signal.c:780 [inline]
handle_signal arch/x86/kernel/signal.c:824 [inline]
arch_do_signal_or_restart+0x679/0x12c0 arch/x86/kernel/signal.c:869
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fbff15ce797
Code: 83 c8 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
RSP: 002b:00007fbfef828028 EFLAGS: 00000246
RAX: 0000000000000048 RBX: 00007fbff1847fa0 RCX: 00007fbff15ce799
RDX: 0000200000000280 RSI: 0000000000000026 RDI: 0000000000000003
RBP: 00007fbff1664bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbff1848038 R14: 00007fbff1847fa0 R15: 00007ffc758b9608
----------------
Code disassembly (best guess):
0: 75 40 jne 0x42
2: 48 c7 04 24 00 00 00 movq $0x0,(%rsp)
9: 00
a: 9c pushf
b: 8f 04 24 pop (%rsp)
e: f7 04 24 00 02 00 00 testl $0x200,(%rsp)
15: 75 46 jne 0x5d
17: 41 f7 c5 00 02 00 00 test $0x200,%r13d
1e: 74 01 je 0x21
20: fb sti
21: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax
28: 00 00
* 2a: 48 3b 44 24 08 cmp 0x8(%rsp),%rax <-- trapping instruction
2f: 75 3c jne 0x6d
31: 89 e8 mov %ebp,%eax
33: 48 83 c4 10 add $0x10,%rsp
37: 5b pop %rbx
38: 41 5c pop %r12
3a: 41 5d pop %r13
3c: 41 5e pop %r14
3e: 41 5f pop %r15