======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc5-syzkaller-g6c52d4da1c74 #0 Not tainted
------------------------------------------------------
syz.7.538/7921 is trying to acquire lock:
ffff8880b8729430 (krc.lock){-.-.}-{2:2}, at: krc_this_cpu_lock kernel/rcu/tree.c:3312 [inline]
ffff8880b8729430 (krc.lock){-.-.}-{2:2}, at: add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3725 [inline]
ffff8880b8729430 (krc.lock){-.-.}-{2:2}, at: kvfree_call_rcu+0x18a/0x790 kernel/rcu/tree.c:3811

but task is already holding lock:
ffff8880b872c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1695 [inline]
ffff8880b872c898 (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:1265 [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:2316 [inline]
       bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2357
       __traceiter_hrtimer_start+0x76/0xd0 include/trace/events/timer.h:222
       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
       check_kcov_mode kernel/kcov.c:185 [inline]
       __sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217
       __page_table_check_pte_clear+0x3f/0x80 mm/page_table_check.c:169
       get_and_clear_full_ptes include/linux/pgtable.h:684 [inline]
       zap_present_folio_ptes mm/memory.c:1496 [inline]
       zap_present_ptes mm/memory.c:1579 [inline]
       zap_pte_range mm/memory.c:1621 [inline]
       zap_pmd_range mm/memory.c:1739 [inline]
       zap_pud_range mm/memory.c:1768 [inline]
       zap_p4d_range mm/memory.c:1789 [inline]
       unmap_page_range+0x2a13/0x40e0 mm/memory.c:1810
       unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900
       exit_mmap+0x275/0xc40 mm/mmap.c:1912
       __mmput+0x115/0x390 kernel/fork.c:1347
       exit_mm+0x220/0x310 kernel/exit.c:571
       do_exit+0x9b2/0x28e0 kernel/exit.c:926
       do_group_exit+0x207/0x2c0 kernel/exit.c:1088
       get_signal+0x16a3/0x1740 kernel/signal.c:2917
       arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
       exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
       __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
       syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
       do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
       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 ***

5 locks held by syz.7.538/7921:
 #0: ffff888011b7cd98 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:144 [inline]
 #0: ffff888011b7cd98 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x165/0xc40 mm/mmap.c:1896
 #1: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #1: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #1: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: __pte_offset_map+0x82/0x380 mm/pgtable-generic.c:287
 #2: ffff888033431c18 (ptlock_ptr(ptdesc)#2){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #2: ffff888033431c18 (ptlock_ptr(ptdesc)#2){+.+.}-{2:2}, at: __pte_offset_map_lock+0x1ba/0x300 mm/pgtable-generic.c:375
 #3: ffff8880b872c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1695 [inline]
 #3: ffff8880b872c898 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x670/0xd50 kernel/time/hrtimer.c:1755
 #4: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #4: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #4: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2315 [inline]
 #4: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1fc/0x540 kernel/trace/bpf_trace.c:2357

stack backtrace:
CPU: 1 UID: 0 PID: 7921 Comm: syz.7.538 Not tainted 6.12.0-rc5-syzkaller-g6c52d4da1c74 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <IRQ>
 __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:1265 [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:2316 [inline]
 bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2357
 __traceiter_hrtimer_start+0x76/0xd0 include/trace/events/timer.h:222
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217
Code: c0 d7 03 00 65 8b 15 90 fd 6e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc
RSP: 0018:ffffc9000473f2d0 EFLAGS: 00000246
RAX: ffffffff820b716f RBX: 0000000000000005 RCX: ffff8880271a5a00
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000005
RBP: ffffc9000473f610 R08: ffffffff820b7160 R09: 1ffffd4000301e30
R10: dffffc0000000000 R11: fffff94000301e31 R12: ffffffff8ea3a180
R13: 1ffff1100536a01f R14: 80000000603c6007 R15: ffff888011b7cc00
 __page_table_check_pte_clear+0x3f/0x80 mm/page_table_check.c:169
 get_and_clear_full_ptes include/linux/pgtable.h:684 [inline]
 zap_present_folio_ptes mm/memory.c:1496 [inline]
 zap_present_ptes mm/memory.c:1579 [inline]
 zap_pte_range mm/memory.c:1621 [inline]
 zap_pmd_range mm/memory.c:1739 [inline]
 zap_pud_range mm/memory.c:1768 [inline]
 zap_p4d_range mm/memory.c:1789 [inline]
 unmap_page_range+0x2a13/0x40e0 mm/memory.c:1810
 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1900
 exit_mmap+0x275/0xc40 mm/mmap.c:1912
 __mmput+0x115/0x390 kernel/fork.c:1347
 exit_mm+0x220/0x310 kernel/exit.c:571
 do_exit+0x9b2/0x28e0 kernel/exit.c:926
 do_group_exit+0x207/0x2c0 kernel/exit.c:1088
 get_signal+0x16a3/0x1740 kernel/signal.c:2917
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2d46b7e719
Code: Unable to access opcode bytes at 0x7f2d46b7e6ef.
RSP: 002b:00007f2d47970038 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: 0000000000000024 RBX: 00007f2d46d35f80 RCX: 00007f2d46b7e719
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000025
RBP: 00007f2d46bf132e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2d46d35f80 R15: 00007ffdbe8da388
 </TASK>
----------------
Code disassembly (best guess):
   0:	c0 d7 03             	rcl    $0x3,%bh
   3:	00 65 8b             	add    %ah,-0x75(%rbp)
   6:	15 90 fd 6e 7e       	adc    $0x7e6efd90,%eax
   b:	81 e2 00 01 ff 00    	and    $0xff0100,%edx
  11:	74 11                	je     0x24
  13:	81 fa 00 01 00 00    	cmp    $0x100,%edx
  19:	75 35                	jne    0x50
  1b:	83 b9 1c 16 00 00 00 	cmpl   $0x0,0x161c(%rcx)
  22:	74 2c                	je     0x50
  24:	8b 91 f8 15 00 00    	mov    0x15f8(%rcx),%edx
* 2a:	83 fa 02             	cmp    $0x2,%edx <-- trapping instruction
  2d:	75 21                	jne    0x50
  2f:	48 8b 91 00 16 00 00 	mov    0x1600(%rcx),%rdx
  36:	48 8b 32             	mov    (%rdx),%rsi
  39:	48 8d 7e 01          	lea    0x1(%rsi),%rdi
  3d:	8b                   	.byte 0x8b
  3e:	89 fc                	mov    %edi,%esp