======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.8.3804/18596 is trying to acquire lock:
ffff88804b508a38 (&trie->lock){-...}-{2:2}, at: trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467
but task is already holding lock:
ffff8880b902a258 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_interrupt+0xf8/0x8d0 kernel/time/hrtimer.c:1792
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (hrtimer_bases.lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
lock_hrtimer_base kernel/time/hrtimer.c:168 [inline]
hrtimer_start_range_ns+0xff/0xc20 kernel/time/hrtimer.c:1284
hrtimer_start include/linux/hrtimer.h:420 [inline]
run_page_cache_worker kernel/rcu/tree.c:3492 [inline]
kvfree_call_rcu+0x61b/0x7d0 kernel/rcu/tree.c:3603
rtnl_register_internal+0x489/0x590 net/core/rtnetlink.c:225
rtnl_register+0x2e/0x70 net/core/rtnetlink.c:275
ip_rt_init+0x2e0/0x3a0 net/ipv4/route.c:3755
ip_init+0xa/0x20 net/ipv4/ip_output.c:1758
inet_init+0x28b/0x3a0 net/ipv4/af_inet.c:2007
do_one_initcall+0x272/0x730 init/main.c:1316
do_initcall_level+0x137/0x1f0 init/main.c:1389
do_initcalls+0x4b/0x90 init/main.c:1405
kernel_init_freeable+0x3e9/0x570 init/main.c:1629
kernel_init+0x19/0x1b0 init/main.c:1520
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
-> #1 (krc.lock){..-.}-{2:2}:
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
krc_this_cpu_lock kernel/rcu/tree.c:3203 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3510 [inline]
kvfree_call_rcu+0x18d/0x7d0 kernel/rcu/tree.c:3601
trie_update_elem+0x86c/0xc50 kernel/bpf/lpm_trie.c:396
bpf_map_update_value+0x57d/0x650 kernel/bpf/syscall.c:223
generic_map_update_batch+0x52d/0x7d0 kernel/bpf/syscall.c:1430
bpf_map_do_batch+0x466/0x600 kernel/bpf/syscall.c:-1
__sys_bpf+0x671/0x6f0 kernel/bpf/syscall.c:-1
__do_sys_bpf kernel/bpf/syscall.c:4761 [inline]
__se_sys_bpf kernel/bpf/syscall.c:4759 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4759
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
-> #0 (&trie->lock){-...}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467
bpf_prog_2c29ac5cdc6b1842+0x3a/0x7a8
bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline]
__bpf_prog_run include/linux/filter.h:621 [inline]
bpf_prog_run include/linux/filter.h:635 [inline]
BPF_PROG_RUN_ARRAY include/linux/bpf.h:1439 [inline]
trace_call_bpf+0x32d/0x5b0 kernel/trace/bpf_trace.c:127
perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:10016
perf_trace_lock_acquire+0x340/0x3e0 include/trace/events/lock.h:13
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0x3d7/0x400 kernel/locking/lockdep.c:5594
seqcount_lockdep_reader_access+0xcd/0x1d0 include/linux/seqlock.h:103
ktime_get_update_offsets_now+0x44/0x3e0 kernel/time/timekeeping.c:2300
hrtimer_update_base kernel/time/hrtimer.c:621 [inline]
hrtimer_interrupt+0x130/0x8d0 kernel/time/hrtimer.c:1793
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194
try_to_wake_up+0x69d/0x1050 kernel/sched/core.c:4167
wake_up_process kernel/sched/core.c:4234 [inline]
wake_up_q+0x78/0xc0 kernel/sched/core.c:953
futex_wake+0x4a9/0x540 kernel/futex/core.c:1702
do_futex+0xd73/0x12b0 kernel/futex/core.c:3988
__do_sys_futex kernel/futex/core.c:4060 [inline]
__se_sys_futex+0x389/0x420 kernel/futex/core.c:4041
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
other info that might help us debug this:
Chain exists of:
&trie->lock --> krc.lock --> hrtimer_bases.lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(hrtimer_bases.lock);
lock(krc.lock);
lock(hrtimer_bases.lock);
lock(&trie->lock);
*** DEADLOCK ***
2 locks held by syz.8.3804/18596:
#0: ffff8880b902a258 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_interrupt+0xf8/0x8d0 kernel/time/hrtimer.c:1792
#1: ffffffff8c31f360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312
stack backtrace:
CPU: 0 PID: 18596 Comm: syz.8.3804 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
check_noncircular+0x296/0x330 kernel/locking/lockdep.c:2133
check_prev_add kernel/locking/lockdep.c:3053 [inline]
check_prevs_add kernel/locking/lockdep.c:3172 [inline]
validate_chain kernel/locking/lockdep.c:3788 [inline]
__lock_acquire+0x2c42/0x7d10 kernel/locking/lockdep.c:5012
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162
trie_delete_elem+0x90/0x710 kernel/bpf/lpm_trie.c:467
bpf_prog_2c29ac5cdc6b1842+0x3a/0x7a8
bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline]
__bpf_prog_run include/linux/filter.h:621 [inline]
bpf_prog_run include/linux/filter.h:635 [inline]
BPF_PROG_RUN_ARRAY include/linux/bpf.h:1439 [inline]
trace_call_bpf+0x32d/0x5b0 kernel/trace/bpf_trace.c:127
perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:10016
perf_trace_lock_acquire+0x340/0x3e0 include/trace/events/lock.h:13
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0x3d7/0x400 kernel/locking/lockdep.c:5594
seqcount_lockdep_reader_access+0xcd/0x1d0 include/linux/seqlock.h:103
ktime_get_update_offsets_now+0x44/0x3e0 kernel/time/timekeeping.c:2300
hrtimer_update_base kernel/time/hrtimer.c:621 [inline]
hrtimer_interrupt+0x130/0x8d0 kernel/time/hrtimer.c:1793
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 4f 9d 8b f7 65 8b 05 70 86 3b 76 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc9000373fa40 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: 9863929d09daf400
RDX: dffffc0000000000 RSI: ffffffff8a2b3180 RDI: 0000000000000001
RBP: ffffc9000373fac0 R08: ffff888025cd8a13 R09: 1ffff11004b9b142
R10: dffffc0000000000 R11: ffffed1004b9b143 R12: dffffc0000000000
R13: ffff888025cd8000 R14: ffff888025cd8a10 R15: 1ffff920006e7f48
try_to_wake_up+0x69d/0x1050 kernel/sched/core.c:4167
wake_up_process kernel/sched/core.c:4234 [inline]
wake_up_q+0x78/0xc0 kernel/sched/core.c:953
futex_wake+0x4a9/0x540 kernel/futex/core.c:1702
do_futex+0xd73/0x12b0 kernel/futex/core.c:3988
__do_sys_futex kernel/futex/core.c:4060 [inline]
__se_sys_futex+0x389/0x420 kernel/futex/core.c:4041
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f99414f5e59
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:00007f993f72e0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f994176f098 RCX: 00007f99414f5e59
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f994176f09c
RBP: 00007f994176f090 R08: 0009b6eac835f3c4 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f994176f128 R14: 00007ffe57d2eaa0 R15: 00007ffe57d2eb88
----------------
Code disassembly (best guess):
0: c7 44 24 20 00 00 00 movl $0x0,0x20(%rsp)
7: 00
8: 9c pushf
9: 8f 44 24 20 pop 0x20(%rsp)
d: f7 44 24 20 00 02 00 testl $0x200,0x20(%rsp)
14: 00
15: 41 c6 04 07 f8 movb $0xf8,(%r15,%rax,1)
1a: 75 4b jne 0x67
1c: f7 c3 00 02 00 00 test $0x200,%ebx
22: 74 01 je 0x25
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 4f 9d 8b f7 call 0xf78b9d7e <-- trapping instruction
2f: 65 8b 05 70 86 3b 76 mov %gs:0x763b8670(%rip),%eax # 0x763b86a6
36: 85 c0 test %eax,%eax
38: 74 3c je 0x76
3a: 48 rex.W
3b: c7 .byte 0xc7
3c: 04 24 add $0x24,%al
3e: 0e (bad)
3f: 36 ss