====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc5-syzkaller-01452-ga9e7715ce8b3 #0 Not tainted ------------------------------------------------------ syz-executor.0/5309 is trying to acquire lock: ffff8880b9529430 (krc.lock){..-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:2960 [inline] ffff8880b9529430 (krc.lock){..-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3359 [inline] ffff8880b9529430 (krc.lock){..-.}-{2:2}, at: kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3444 but task is already holding lock: ffff8880b952c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: lock_hrtimer_base kernel/time/hrtimer.c:175 [inline] ffff8880b952c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_start_range_ns+0xdf/0xc60 kernel/time/hrtimer.c:1303 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (hrtimer_bases.lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 lock_hrtimer_base kernel/time/hrtimer.c:175 [inline] hrtimer_start_range_ns+0xdf/0xc60 kernel/time/hrtimer.c:1303 hrtimer_start include/linux/hrtimer.h:275 [inline] run_page_cache_worker kernel/rcu/tree.c:3341 [inline] kvfree_call_rcu+0x5e6/0x790 kernel/rcu/tree.c:3446 rtnl_register_internal+0x482/0x590 net/core/rtnetlink.c:265 rtnl_register+0x36/0x80 net/core/rtnetlink.c:315 ip_rt_init+0x2f5/0x3a0 net/ipv4/route.c:3708 ip_init+0xe/0x20 net/ipv4/ip_output.c:1663 inet_init+0x3d8/0x580 net/ipv4/af_inet.c:2023 do_one_initcall+0x248/0x880 init/main.c:1245 do_initcall_level+0x157/0x210 init/main.c:1307 do_initcalls+0x3f/0x80 init/main.c:1323 kernel_init_freeable+0x435/0x5d0 init/main.c:1555 kernel_init+0x1d/0x2b0 init/main.c:1444 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #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+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 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:2960 [inline] add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3359 [inline] kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3444 trie_delete_elem+0x546/0x6a0 kernel/bpf/lpm_trie.c:540 bpf_prog_98d5f67702aee616+0x42/0x4b bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2403 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2444 trace_hrtimer_start include/trace/events/timer.h:222 [inline] debug_activate kernel/time/hrtimer.c:479 [inline] enqueue_hrtimer+0x35a/0x3c0 kernel/time/hrtimer.c:1090 __hrtimer_start_range_ns kernel/time/hrtimer.c:1265 [inline] hrtimer_start_range_ns+0xaa0/0xc60 kernel/time/hrtimer.c:1305 futex_wait_queue+0xb0/0x1d0 kernel/futex/waitwake.c:357 __futex_wait+0x17f/0x320 kernel/futex/waitwake.c:669 futex_wait+0x101/0x360 kernel/futex/waitwake.c:697 do_futex+0x33b/0x560 kernel/futex/syscalls.c:102 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex+0x3f9/0x480 kernel/futex/syscalls.c:160 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f 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 *** 2 locks held by syz-executor.0/5309: #0: ffff8880b952c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: lock_hrtimer_base kernel/time/hrtimer.c:175 [inline] #0: ffff8880b952c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_start_range_ns+0xdf/0xc60 kernel/time/hrtimer.c:1303 #1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2402 [inline] #1: ffffffff8e334e20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1fc/0x540 kernel/trace/bpf_trace.c:2444 stack backtrace: CPU: 1 PID: 5309 Comm: syz-executor.0 Not tainted 6.9.0-rc5-syzkaller-01452-ga9e7715ce8b3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 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+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 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:2960 [inline] add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3359 [inline] kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3444 trie_delete_elem+0x546/0x6a0 kernel/bpf/lpm_trie.c:540 bpf_prog_98d5f67702aee616+0x42/0x4b bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2403 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2444 trace_hrtimer_start include/trace/events/timer.h:222 [inline] debug_activate kernel/time/hrtimer.c:479 [inline] enqueue_hrtimer+0x35a/0x3c0 kernel/time/hrtimer.c:1090 __hrtimer_start_range_ns kernel/time/hrtimer.c:1265 [inline] hrtimer_start_range_ns+0xaa0/0xc60 kernel/time/hrtimer.c:1305 futex_wait_queue+0xb0/0x1d0 kernel/futex/waitwake.c:357 __futex_wait+0x17f/0x320 kernel/futex/waitwake.c:669 futex_wait+0x101/0x360 kernel/futex/waitwake.c:697 do_futex+0x33b/0x560 kernel/futex/syscalls.c:102 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex+0x3f9/0x480 kernel/futex/syscalls.c:160 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4b0767dca9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff467626c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00000000000156df RCX: 00007f4b0767dca9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4b077ac12c RBP: 00007fff467627d0 R08: 00007f4b082f80b0 R09: 000000000000007c R10: 00007fff467627b0 R11: 0000000000000246 R12: 0000000000015711 R13: 00007f4b077ac12c R14: 00007fff467627b0 R15: 0000000000000032