===================================== WARNING: bad unlock balance detected! syzkaller #0 Not tainted ------------------------------------- udevd/5621 is trying to release lock (rcu_read_lock) at: [] mmu_notifier_invalidate_range_start include/linux/mmu_notifier.h:475 [inline] [] wp_page_copy mm/memory.c:3890 [inline] [] do_wp_page+0x37b4/0x4cc0 mm/memory.c:4320 but there are no more locks to release! other info that might help us debug this: 1 lock held by udevd/5621: #0: ffff888034782a88 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 stack backtrace: CPU: 1 UID: 0 PID: 5621 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_unlock_imbalance_bug+0xdc/0xf0 kernel/locking/lockdep.c:5298 __lock_release kernel/locking/lockdep.c:5537 [inline] lock_release+0x248/0x3c0 kernel/locking/lockdep.c:5889 rcu_lock_release include/linux/rcupdate.h:310 [inline] rcu_read_unlock include/linux/rcupdate.h:869 [inline] pte_unmap include/linux/pgtable.h:117 [inline] wp_page_copy mm/memory.c:3960 [inline] do_wp_page+0x4076/0x4cc0 mm/memory.c:4320 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault mm/memory.c:6549 [inline] handle_mm_fault+0x151d/0x3170 mm/memory.c:6718 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x55e029c89346 Code: 74 0c 48 8b 8e 88 01 00 00 48 85 c9 75 66 bf 01 00 00 00 48 89 e5 e8 d9 b3 ff ff 48 8d 15 9e d9 00 00 be 16 00 00 00 48 89 ef <48> 89 83 88 01 00 00 48 89 c1 31 c0 e8 59 c8 fd ff c6 83 b4 01 00 RSP: 002b:00007ffd9218b930 EFLAGS: 00010202 RAX: 0000000006aa6d81 RBX: 000055e051c25ba0 RCX: 00000000000cb3c1 RDX: 000055e029c96cdc RSI: 0000000000000016 RDI: 00007ffd9218b930 RBP: 00007ffd9218b930 R08: 0000000006aa6d81 R09: 3fffffffffffffff R10: 4000000000000000 R11: 0000000000000000 R12: 000000000aba9500 R13: 0000000003938700 R14: 000055e029cad100 R15: 000055e029cad140 ------------[ cut here ]------------ rrln < 0 || rrln > RCU_NEST_PMAX WARNING: kernel/rcu/tree_plugin.h:443 at __rcu_read_unlock+0x79/0xe0 kernel/rcu/tree_plugin.h:443, CPU#0: udevd/5621 Modules linked in: CPU: 0 UID: 0 PID: 5621 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:__rcu_read_unlock+0x79/0xe0 kernel/rcu/tree_plugin.h:443 Code: 75 66 41 83 3e 00 75 27 43 0f b6 04 3c 84 c0 75 41 8b 03 3d 00 00 00 40 73 0f 5b 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc cc 90 <0f> 0b 90 eb eb e8 6d 00 00 00 eb d2 89 d9 80 e1 07 80 c1 03 38 c1 RSP: 0000:ffffc90003967a50 EFLAGS: 00010286 RAX: 00000000ffffffff RBX: ffff8880373f2384 RCX: 0000000000000046 RDX: 0000000000000000 RSI: ffffffff8e218610 RDI: ffff8880373f1ec0 RBP: ffffc90003967c10 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff1d06d14 R12: 1ffff11006e7e470 R13: dffffc0000000000 R14: ffffea0000499240 R15: dffffc0000000000 FS: 00007fa0d47b6880(0000) GS:ffff888125290000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa0d47b66e8 CR3: 0000000075686000 CR4: 00000000003526f0 Call Trace: rcu_read_unlock include/linux/rcupdate.h:871 [inline] pte_unmap include/linux/pgtable.h:117 [inline] wp_page_copy mm/memory.c:3960 [inline] do_wp_page+0x407b/0x4cc0 mm/memory.c:4320 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault mm/memory.c:6549 [inline] handle_mm_fault+0x151d/0x3170 mm/memory.c:6718 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x55e029c89346 Code: 74 0c 48 8b 8e 88 01 00 00 48 85 c9 75 66 bf 01 00 00 00 48 89 e5 e8 d9 b3 ff ff 48 8d 15 9e d9 00 00 be 16 00 00 00 48 89 ef <48> 89 83 88 01 00 00 48 89 c1 31 c0 e8 59 c8 fd ff c6 83 b4 01 00 RSP: 002b:00007ffd9218b930 EFLAGS: 00010202 RAX: 0000000006aa6d81 RBX: 000055e051c25ba0 RCX: 00000000000cb3c1 RDX: 000055e029c96cdc RSI: 0000000000000016 RDI: 00007ffd9218b930 RBP: 00007ffd9218b930 R08: 0000000006aa6d81 R09: 3fffffffffffffff R10: 4000000000000000 R11: 0000000000000000 R12: 000000000aba9500 R13: 0000000003938700 R14: 000055e029cad100 R15: 000055e029cad140