============================================ WARNING: possible recursive locking detected 5.15.164-syzkaller #0 Not tainted -------------------------------------------- syz.1.430/4795 is trying to acquire lock: ffff8880b9a35bb8 (lock#9){+.+.}-{2:2}, at: local_lock_acquire+0xd/0x170 include/linux/local_lock_internal.h:28 but task is already holding lock: ffff8880b9a35bb8 (lock#9){+.+.}-{2:2}, at: local_lock_acquire+0xd/0x170 include/linux/local_lock_internal.h:28 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(lock#9); lock(lock#9); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by syz.1.430/4795: #0: ffff88807df77828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #0: ffff88807df77828 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault arch/x86/mm/fault.c:1298 [inline] #0: ffff88807df77828 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fault arch/x86/mm/fault.c:1445 [inline] #0: ffff88807df77828 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault+0x181/0x700 arch/x86/mm/fault.c:1501 #1: ffff8880b9a35bb8 (lock#9){+.+.}-{2:2}, at: local_lock_acquire+0xd/0x170 include/linux/local_lock_internal.h:28 #2: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 #3: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 #4: ffff88807df77828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline] #4: ffff88807df77828 (&mm->mmap_lock){++++}-{3:3}, at: stack_map_get_build_id_offset+0x23e/0x930 kernel/bpf/stackmap.c:185 stack backtrace: CPU: 0 PID: 4795 Comm: syz.1.430 Not tainted 5.15.164-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2946 [inline] check_deadlock kernel/locking/lockdep.c:2989 [inline] validate_chain+0x46d2/0x5930 kernel/locking/lockdep.c:3775 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 local_lock_acquire+0x29/0x170 include/linux/local_lock_internal.h:29 __mmap_lock_do_trace_acquire_returned+0x7c/0x340 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:137 [inline] stack_map_get_build_id_offset+0x612/0x930 kernel/bpf/stackmap.c:185 __bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:496 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1490 [inline] bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1480 bpf_prog_ec3b2eefa702d8d3+0x3a/0xb50 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline] bpf_trace_run4+0x1ea/0x390 kernel/trace/bpf_trace.c:1919 trace_mmap_lock_acquire_returned include/trace/events/mmap_lock.h:44 [inline] __mmap_lock_do_trace_acquire_returned+0x2d6/0x340 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:137 [inline] do_user_addr_fault arch/x86/mm/fault.c:1298 [inline] handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x564/0x700 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0033:0x7f843de8c766 Code: ff 48 83 e8 01 48 89 d6 bf 01 00 00 00 48 c1 e0 0e 48 c1 ee 06 48 01 c8 48 89 d1 81 e6 ff 3f 00 00 48 c1 e9 03 83 e1 07 d3 e7 <40> 84 bc 06 20 20 00 00 0f 85 27 fd ff ff e9 ce fd ff ff e8 22 5e RSP: 002b:00007ffe7b169a20 EFLAGS: 00010202 RAX: 000000110c2f4000 RBX: 00007f843ec79720 RCX: 0000000000000006 RDX: ffffffff843194f2 RSI: 0000000000000653 RDI: 0000000000000040 RBP: 0000000000000000 R08: 00007f843e134000 R09: 00007f843e136000 R10: 00000000843194f6 R11: 0000000000000005 R12: ffffffff84319c3d R13: 00007f843e14a018 R14: 0000000000000008 R15: 000000000000030e