====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc6-next-20240501-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/9038 is trying to acquire lock: ffff8880b9429430 (krc.lock){-.-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:3329 [inline] ffff8880b9429430 (krc.lock){-.-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3728 [inline] ffff8880b9429430 (krc.lock){-.-.}-{2:2}, at: kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3813 but task is already holding lock: ffff8880b942c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: lock_hrtimer_base kernel/time/hrtimer.c:175 [inline] ffff8880b942c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_start_range_ns+0xdf/0xc60 kernel/time/hrtimer.c:1298 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:1298 hrtimer_start include/linux/hrtimer.h:275 [inline] run_page_cache_worker kernel/rcu/tree.c:3710 [inline] kvfree_call_rcu+0x5e6/0x790 kernel/rcu/tree.c:3815 rtnl_register_internal+0x482/0x590 net/core/rtnetlink.c:265 rtnl_register+0x36/0x80 net/core/rtnetlink.c:315 ip_rt_init+0x2fc/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:1265 do_initcall_level+0x157/0x210 init/main.c:1327 do_initcalls+0x3f/0x80 init/main.c:1343 kernel_init_freeable+0x435/0x5d0 init/main.c:1576 kernel_init+0x1d/0x2b0 init/main.c:1465 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:3329 [inline] add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3728 [inline] kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3813 trie_delete_elem+0x546/0x6a0 kernel/bpf/lpm_trie.c:540 bpf_prog_2c29ac5cdc6b1842+0x42/0x46 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:1085 __hrtimer_start_range_ns kernel/time/hrtimer.c:1260 [inline] hrtimer_start_range_ns+0xaa0/0xc60 kernel/time/hrtimer.c:1300 common_timer_set+0x3d2/0x4e0 kernel/time/posix-timers.c:895 do_timer_settime+0x257/0x340 kernel/time/posix-timers.c:925 __do_sys_timer_settime kernel/time/posix-timers.c:954 [inline] __se_sys_timer_settime kernel/time/posix-timers.c:940 [inline] __x64_sys_timer_settime+0x19e/0x240 kernel/time/posix-timers.c:940 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 *** 3 locks held by syz-executor.2/9038: #0: ffff88802cefc1b0 (&new_timer->it_lock){-...}-{2:2}, at: __lock_timer+0x2ae/0x3f0 kernel/time/posix-timers.c:595 #1: ffff8880b942c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: lock_hrtimer_base kernel/time/hrtimer.c:175 [inline] #1: ffff8880b942c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: hrtimer_start_range_ns+0xdf/0xc60 kernel/time/hrtimer.c:1298 #2: ffffffff8e333da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #2: ffffffff8e333da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8e333da0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2402 [inline] #2: ffffffff8e333da0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1fc/0x540 kernel/trace/bpf_trace.c:2444 stack backtrace: CPU: 0 PID: 9038 Comm: syz-executor.2 Not tainted 6.9.0-rc6-next-20240501-syzkaller #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:3329 [inline] add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3728 [inline] kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3813 trie_delete_elem+0x546/0x6a0 kernel/bpf/lpm_trie.c:540 bpf_prog_2c29ac5cdc6b1842+0x42/0x46 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:1085 __hrtimer_start_range_ns kernel/time/hrtimer.c:1260 [inline] hrtimer_start_range_ns+0xaa0/0xc60 kernel/time/hrtimer.c:1300 common_timer_set+0x3d2/0x4e0 kernel/time/posix-timers.c:895 do_timer_settime+0x257/0x340 kernel/time/posix-timers.c:925 __do_sys_timer_settime kernel/time/posix-timers.c:954 [inline] __se_sys_timer_settime kernel/time/posix-timers.c:940 [inline] __x64_sys_timer_settime+0x19e/0x240 kernel/time/posix-timers.c:940 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: 0033:0x7fa44747dea9 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:00007fa4481050c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000df RAX: ffffffffffffffda RBX: 00007fa4475abf80 RCX: 00007fa44747dea9 RDX: 0000000020000200 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fa4474ca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fa4475abf80 R15: 00007ffe5614a4d8