======================================================
WARNING: possible circular locking dependency detected
6.6.94-syzkaller #0 Not tainted
------------------------------------------------------
syz.4.558/7498 is trying to acquire lock:
ffff8880b8f295a8 (krc.lock){-.-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:2955 [inline]
ffff8880b8f295a8 (krc.lock){-.-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3364 [inline]
ffff8880b8f295a8 (krc.lock){-.-.}-{2:2}, at: kvfree_call_rcu+0x15a/0x780 kernel/rcu/tree.c:3449
but task is already holding lock:
ffff8880b8f2b958 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1759 [inline]
ffff8880b8f2b958 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x5e3/0xc40 kernel/time/hrtimer.c:1819
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (hrtimer_bases.lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162
lock_hrtimer_base kernel/time/hrtimer.c:181 [inline]
hrtimer_start_range_ns+0xf3/0x1000 kernel/time/hrtimer.c:1354
hrtimer_start include/linux/hrtimer.h:421 [inline]
run_page_cache_worker kernel/rcu/tree.c:3346 [inline]
kvfree_call_rcu+0x5d5/0x780 kernel/rcu/tree.c:3451
rtnl_register_internal+0x486/0x590 net/core/rtnetlink.c:264
rtnl_register+0x32/0x70 net/core/rtnetlink.c:314
ip_rt_init+0x2ec/0x390 net/ipv4/route.c:3789
ip_init+0xe/0x20 net/ipv4/ip_output.c:1663
inet_init+0x2c1/0x3e0 net/ipv4/af_inet.c:2024
do_one_initcall+0x1fd/0x750 init/main.c:1238
do_initcall_level+0x137/0x1f0 init/main.c:1300
do_initcalls+0x69/0xd0 init/main.c:1316
kernel_init_freeable+0x3d2/0x570 init/main.c:1553
kernel_init+0x1d/0x1c0 init/main.c:1443
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
-> #0 (krc.lock){-.-.}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
krc_this_cpu_lock kernel/rcu/tree.c:2955 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3364 [inline]
kvfree_call_rcu+0x15a/0x780 kernel/rcu/tree.c:3449
trie_delete_elem+0x535/0x6a0 kernel/bpf/lpm_trie.c:545
bpf_prog_5186c38a4019a4cb+0x4a/0x4e
bpf_dispatcher_nop_func include/linux/bpf.h:1213 [inline]
__bpf_prog_run include/linux/filter.h:612 [inline]
bpf_prog_run include/linux/filter.h:619 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline]
bpf_trace_run2+0x1d1/0x3c0 kernel/trace/bpf_trace.c:2361
__bpf_trace_hrtimer_start+0xfb/0x150 include/trace/events/timer.h:202
trace_hrtimer_start include/trace/events/timer.h:202 [inline]
debug_activate kernel/time/hrtimer.c:506 [inline]
enqueue_hrtimer+0x318/0x370 kernel/time/hrtimer.c:1113
__run_hrtimer kernel/time/hrtimer.c:1772 [inline]
__hrtimer_run_queues+0x637/0xc40 kernel/time/hrtimer.c:1819
hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1881
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
__sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
_compound_head include/linux/page-flags.h:246 [inline]
PageAnon include/linux/page-flags.h:684 [inline]
zap_pte_range mm/memory.c:1440 [inline]
zap_pmd_range mm/memory.c:1570 [inline]
zap_pud_range mm/memory.c:1599 [inline]
zap_p4d_range mm/memory.c:1620 [inline]
unmap_page_range+0xe6b/0x2fe0 mm/memory.c:1641
unmap_vmas+0x25e/0x3a0 mm/memory.c:1731
exit_mmap+0x200/0xb50 mm/mmap.c:3292
__mmput+0x118/0x3c0 kernel/fork.c:1355
copy_process+0x294b/0x3d70 kernel/fork.c:2765
kernel_clone+0x21b/0x840 kernel/fork.c:2914
__do_sys_clone kernel/fork.c:3057 [inline]
__se_sys_clone kernel/fork.c:3041 [inline]
__x64_sys_clone+0x18c/0x1e0 kernel/fork.c:3041
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(hrtimer_bases.lock);
lock(krc.lock);
lock(hrtimer_bases.lock);
lock(krc.lock);
*** DEADLOCK ***
5 locks held by syz.4.558/7498:
#0: ffff8880323c14a0 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:146 [inline]
#0: ffff8880323c14a0 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x14a/0xb50 mm/mmap.c:3277
#1: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#1: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#1: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: __pte_offset_map+0x2c/0x2c0 mm/pgtable-generic.c:287
#2: ffff888017866618 (ptlock_ptr(ptdesc)#2){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff888017866618 (ptlock_ptr(ptdesc)#2){+.+.}-{2:2}, at: __pte_offset_map_lock+0x107/0x1e0 mm/pgtable-generic.c:375
#3: ffff8880b8f2b958 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1759 [inline]
#3: ffff8880b8f2b958 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x5e3/0xc40 kernel/time/hrtimer.c:1819
#4: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#4: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#4: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2321 [inline]
#4: ffffffff8cd2f760 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xde/0x3c0 kernel/trace/bpf_trace.c:2361
stack backtrace:
CPU: 1 PID: 7498 Comm: syz.4.558 Not tainted 6.6.94-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
check_noncircular+0x2bd/0x3c0 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
krc_this_cpu_lock kernel/rcu/tree.c:2955 [inline]
add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3364 [inline]
kvfree_call_rcu+0x15a/0x780 kernel/rcu/tree.c:3449
trie_delete_elem+0x535/0x6a0 kernel/bpf/lpm_trie.c:545
bpf_prog_5186c38a4019a4cb+0x4a/0x4e
bpf_dispatcher_nop_func include/linux/bpf.h:1213 [inline]
__bpf_prog_run include/linux/filter.h:612 [inline]
bpf_prog_run include/linux/filter.h:619 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2322 [inline]
bpf_trace_run2+0x1d1/0x3c0 kernel/trace/bpf_trace.c:2361
__bpf_trace_hrtimer_start+0xfb/0x150 include/trace/events/timer.h:202
trace_hrtimer_start include/trace/events/timer.h:202 [inline]
debug_activate kernel/time/hrtimer.c:506 [inline]
enqueue_hrtimer+0x318/0x370 kernel/time/hrtimer.c:1113
__run_hrtimer kernel/time/hrtimer.c:1772 [inline]
__hrtimer_run_queues+0x637/0xc40 kernel/time/hrtimer.c:1819
hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1881
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
__sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:_compound_head include/linux/page-flags.h:246 [inline]
RIP: 0010:PageAnon include/linux/page-flags.h:684 [inline]
RIP: 0010:zap_pte_range mm/memory.c:1440 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1570 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1599 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:1620 [inline]
RIP: 0010:unmap_page_range+0xe6b/0x2fe0 mm/memory.c:1641
Code: 0f 85 e6 0a 00 00 80 0a 10 4d 85 f6 0f 84 2f 09 00 00 49 8d 5e 08 48 89 d8 48 c1 e8 03 48 89 84 24 e8 00 00 00 42 80 3c 28 00 <74> 08 48 89 df e8 cb 9b 15 00 4c 8b 3b 4c 89 fe 48 83 e6 01 31 ff
RSP: 0018:ffffc90003a374e0 EFLAGS: 00000246
RAX: 1ffffd400035c2d9 RBX: ffffea0001ae16c8 RCX: 00007fd48bc46000
RDX: ffffc90003a378e0 RSI: 000000000007ffff RDI: ffffc90003a378d8
RBP: ffffc90003a376d0 R08: ffffffff8e49ab2f R09: 1ffffffff1c93565
R10: dffffc0000000000 R11: fffffbfff1c93566 R12: 00007fd48be00000
R13: dffffc0000000000 R14: ffffea0001ae16c0 R15: ffffffffffffffff
unmap_vmas+0x25e/0x3a0 mm/memory.c:1731
exit_mmap+0x200/0xb50 mm/mmap.c:3292
__mmput+0x118/0x3c0 kernel/fork.c:1355
copy_process+0x294b/0x3d70 kernel/fork.c:2765
kernel_clone+0x21b/0x840 kernel/fork.c:2914
__do_sys_clone kernel/fork.c:3057 [inline]
__se_sys_clone kernel/fork.c:3041 [inline]
__x64_sys_clone+0x18c/0x1e0 kernel/fork.c:3041
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd48d78e929
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:00007fd48e692fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fd48d9b5fa0 RCX: 00007fd48d78e929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000630c1000
RBP: 00007fd48d810b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd48d9b5fa0 R15: 00007ffe4bfa0658
----------------
Code disassembly (best guess):
0: 0f 85 e6 0a 00 00 jne 0xaec
6: 80 0a 10 orb $0x10,(%rdx)
9: 4d 85 f6 test %r14,%r14
c: 0f 84 2f 09 00 00 je 0x941
12: 49 8d 5e 08 lea 0x8(%r14),%rbx
16: 48 89 d8 mov %rbx,%rax
19: 48 c1 e8 03 shr $0x3,%rax
1d: 48 89 84 24 e8 00 00 mov %rax,0xe8(%rsp)
24: 00
25: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1)
* 2a: 74 08 je 0x34 <-- trapping instruction
2c: 48 89 df mov %rbx,%rdi
2f: e8 cb 9b 15 00 call 0x159bff
34: 4c 8b 3b mov (%rbx),%r15
37: 4c 89 fe mov %r15,%rsi
3a: 48 83 e6 01 and $0x1,%rsi
3e: 31 ff xor %edi,%edi