------------[ cut here ]------------
WARNING: CPU: 0 PID: 15693 at kernel/rcu/tree_stall.h:1015 rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1015
Modules linked in:
CPU: 0 UID: 0 PID: 15693 Comm: syz.5.3130 Not tainted 6.16.0-rc6-syzkaller-gcd7c97f4584a #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1015
Code: ff ff 48 c7 c7 00 84 af 99 be 04 00 00 00 e8 23 8f 7b 00 4c 89 f7 b8 01 00 00 00 87 05 15 cf 07 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 40 44 14 8e 74 47 48 c7 c0 30 1a a2 8f 48 c1 e8
RSP: 0018:ffffc90000007bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000a02 RCX: ffffffff81a7b4dd
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8e144440
RBP: ffffc90000007e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff335f080 R12: 0000000000002904
R13: 1ffff110170c75fa R14: ffffffff8e144440 R15: dffffc0000000000
FS: 00007fd3fe4506c0(0000) GS:ffff888125c1f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000000 CR3: 000000005dc6e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000200000000300
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
rcu_core+0x5f7/0x1710 kernel/rcu/tree.c:2827
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
sysvec_irq_work+0xa3/0xc0 arch/x86/kernel/irq_work.c:17
asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 cb de 01 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000f17f730 EFLAGS: 00000206
RAX: d5d326bdf02fe100 RBX: 0000000000000000 RCX: d5d326bdf02fe100
RDX: 0000000000000000 RSI: ffffffff8db863d2 RDI: ffffffff8be29f80
RBP: ffffffff84bdae85 R08: 0000000000000000 R09: ffffffff84bdae85
R10: ffff888073e89520 R11: ffff888076f3ceb0 R12: 0000000000000000
R13: ffff888076f3cf80 R14: 0000000000000001 R15: 0000000000000246
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
lockref_get+0x15/0x60 lib/lockref.c:50
dget include/linux/dcache.h:345 [inline]
path_get fs/namei.c:614 [inline]
get_fs_root include/linux/fs_struct.h:31 [inline]
set_root+0x117/0x3b0 fs/namei.c:1020
nd_jump_root+0x2b4/0x430 fs/namei.c:1036
pick_link+0x51f/0xe80 fs/namei.c:1950
step_into+0xc5d/0xf30 fs/namei.c:2008
walk_component fs/namei.c:2144 [inline]
link_path_walk+0x77b/0xea0 fs/namei.c:2506
path_parentat fs/namei.c:2710 [inline]
__filename_parentat+0x246/0x670 fs/namei.c:2734
filename_parentat fs/namei.c:2752 [inline]
filename_create+0xcf/0x470 fs/namei.c:4129
do_mkdirat+0xa0/0x590 fs/namei.c:4400
__do_sys_mkdirat fs/namei.c:4425 [inline]
__se_sys_mkdirat fs/namei.c:4423 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4423
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd3fd58e9a9
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:00007fd3fe450038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fd3fd7b5fa0 RCX: 00007fd3fd58e9a9
RDX: 00000000000001ff RSI: 00002000000000c0 RDI: ffffffffffffff9c
RBP: 00007fd3fd610d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd3fd7b5fa0 R15: 00007ffe7ee7de88
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: 00 00 add %al,(%rax)
4: 9c pushf
5: 8f 44 24 30 pop 0x30(%rsp)
9: f7 44 24 30 00 02 00 testl $0x200,0x30(%rsp)
10: 00
11: 0f 85 cd 00 00 00 jne 0xe4
17: f7 44 24 08 00 02 00 testl $0x200,0x8(%rsp)
1e: 00
1f: 74 01 je 0x22
21: fb sti
22: 65 48 8b 05 cb de 01 mov %gs:0x1101decb(%rip),%rax # 0x1101def5
29: 11
* 2a: 48 3b 44 24 58 cmp 0x58(%rsp),%rax <-- trapping instruction
2f: 0f 85 f2 00 00 00 jne 0x127
35: 48 83 c4 60 add $0x60,%rsp
39: 5b pop %rbx
3a: 41 5c pop %r12
3c: 41 5d pop %r13
3e: 41 5e pop %r14