====================================================== WARNING: possible circular locking dependency detected 6.12.0-rc4-syzkaller-g87cb58aebdf7 #0 Not tainted ------------------------------------------------------ syz.0.8/5929 is trying to acquire lock: ffff8880b8629430 (krc.lock){-.-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:3312 [inline] ffff8880b8629430 (krc.lock){-.-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3725 [inline] ffff8880b8629430 (krc.lock){-.-.}-{2:2}, at: kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3811 but task is already holding lock: ffff8880b862c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1695 [inline] ffff8880b862c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x670/0xd50 kernel/time/hrtimer.c:1755 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:5825 __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+0x109/0xca0 kernel/time/hrtimer.c:1300 hrtimer_start include/linux/hrtimer.h:275 [inline] run_page_cache_worker kernel/rcu/tree.c:3707 [inline] kvfree_call_rcu+0x5e6/0x790 kernel/rcu/tree.c:3813 pwq_release_workfn+0x664/0x800 kernel/workqueue.c:5078 kthread_worker_fn+0x500/0xb70 kernel/kthread.c:844 kthread+0x2f0/0x390 kernel/kthread.c:389 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:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __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:3312 [inline] add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3725 [inline] kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3811 trie_delete_elem+0x546/0x6a0 kernel/bpf/lpm_trie.c:540 bpf_prog_2c29ac5cdc6b1842+0x43/0x47 bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline] __bpf_prog_run include/linux/filter.h:701 [inline] bpf_prog_run include/linux/filter.h:708 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2340 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2381 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 __run_hrtimer kernel/time/hrtimer.c:1708 [inline] __hrtimer_run_queues+0x6cb/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 orc_ip arch/x86/kernel/unwind_orc.c:80 [inline] __orc_find arch/x86/kernel/unwind_orc.c:102 [inline] orc_find arch/x86/kernel/unwind_orc.c:227 [inline] unwind_next_frame+0x6dc/0x22d0 arch/x86/kernel/unwind_orc.c:494 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kmem_cache_free+0x1a2/0x420 mm/slub.c:4681 vma_lock_free kernel/fork.c:458 [inline] __vm_area_free+0xe3/0x110 kernel/fork.c:514 exit_mmap+0x5c6/0xc40 mm/mmap.c:1898 __mmput+0x115/0x390 kernel/fork.c:1347 mmput kernel/fork.c:1369 [inline] dup_mm kernel/fork.c:1690 [inline] copy_mm+0x1a27/0x1f40 kernel/fork.c:1723 copy_process+0x1845/0x3d50 kernel/fork.c:2372 kernel_clone+0x226/0x8f0 kernel/fork.c:2784 __do_sys_clone kernel/fork.c:2927 [inline] __se_sys_clone kernel/fork.c:2911 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2911 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 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.0.8/5929: #0: ffff888024c59e18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:106 [inline] #0: ffff888024c59e18 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x2bd/0xc40 mm/mmap.c:1882 #1: ffff8880b862c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1695 [inline] #1: ffff8880b862c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x670/0xd50 kernel/time/hrtimer.c:1755 #2: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #2: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2339 [inline] #2: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1fc/0x540 kernel/trace/bpf_trace.c:2381 stack backtrace: CPU: 0 UID: 0 PID: 5929 Comm: syz.0.8 Not tainted 6.12.0-rc4-syzkaller-g87cb58aebdf7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __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:3312 [inline] add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3725 [inline] kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3811 trie_delete_elem+0x546/0x6a0 kernel/bpf/lpm_trie.c:540 bpf_prog_2c29ac5cdc6b1842+0x43/0x47 bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline] __bpf_prog_run include/linux/filter.h:701 [inline] bpf_prog_run include/linux/filter.h:708 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2340 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2381 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 __run_hrtimer kernel/time/hrtimer.c:1708 [inline] __hrtimer_run_queues+0x6cb/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:80 [inline] RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:102 [inline] RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline] RIP: 0010:unwind_next_frame+0x6dc/0x22d0 arch/x86/kernel/unwind_orc.c:494 Code: c1 e8 3f 48 01 c8 48 83 e0 fe 49 8d 1c 46 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 48 63 03 <48> 01 d8 48 8d 4b 04 4c 39 f8 4c 0f 46 f1 48 8d 43 fc 48 0f 47 e8 RSP: 0018:ffffc900043bf110 EFLAGS: 00000246 RAX: fffffffff126e2ee RBX: ffffffff902df75c RCX: dffffc0000000000 RDX: 00000000000b0001 RSI: ffffffff90a38d14 RDI: ffffffff814156e0 RBP: ffffffff902df75c R08: 0000000000000001 R09: ffffc900043bf2d0 R10: ffffc900043bf230 R11: ffffffff818090c0 R12: ffffffff902df75c R13: ffffffff902df75c R14: ffffffff902df75c R15: ffffffff8154db54 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:2342 [inline] slab_free mm/slub.c:4579 [inline] kmem_cache_free+0x1a2/0x420 mm/slub.c:4681 vma_lock_free kernel/fork.c:458 [inline] __vm_area_free+0xe3/0x110 kernel/fork.c:514 exit_mmap+0x5c6/0xc40 mm/mmap.c:1898 __mmput+0x115/0x390 kernel/fork.c:1347 mmput kernel/fork.c:1369 [inline] dup_mm kernel/fork.c:1690 [inline] copy_mm+0x1a27/0x1f40 kernel/fork.c:1723 copy_process+0x1845/0x3d50 kernel/fork.c:2372 kernel_clone+0x226/0x8f0 kernel/fork.c:2784 __do_sys_clone kernel/fork.c:2927 [inline] __se_sys_clone kernel/fork.c:2911 [inline] __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2911 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd31017e719 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:00007fd311015fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fd310335f80 RCX: 00007fd31017e719 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fd3101f132e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd310335f80 R15: 00007ffdf49e5bd8 ---------------- Code disassembly (best guess): 0: c1 e8 3f shr $0x3f,%eax 3: 48 01 c8 add %rcx,%rax 6: 48 83 e0 fe and $0xfffffffffffffffe,%rax a: 49 8d 1c 46 lea (%r14,%rax,2),%rbx e: 48 89 d8 mov %rbx,%rax 11: 48 c1 e8 03 shr $0x3,%rax 15: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 1c: fc ff df 1f: 0f b6 04 08 movzbl (%rax,%rcx,1),%eax 23: 84 c0 test %al,%al 25: 75 27 jne 0x4e 27: 48 63 03 movslq (%rbx),%rax * 2a: 48 01 d8 add %rbx,%rax <-- trapping instruction 2d: 48 8d 4b 04 lea 0x4(%rbx),%rcx 31: 4c 39 f8 cmp %r15,%rax 34: 4c 0f 46 f1 cmovbe %rcx,%r14 38: 48 8d 43 fc lea -0x4(%rbx),%rax 3c: 48 0f 47 e8 cmova %rax,%rbp