PANIC: cache destroy: still has partial slabs
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Thread 1320 "mountvolume" running on CPU 0
stack trace for thread 1320 "mountvolume"
    kernel stack: 0xffffffff80729000 to 0xffffffff8072e000
      user stack: 0x00007f54d1c75000 to 0x00007f54d2c75000
frame                       caller             <image>:function + offset
 0 ffffffff8072daf8 (+  16) ffffffff8014133d   <kernel_x86_64> arch_debug_stack_trace + 0x13
 1 ffffffff8072db08 (+  16) ffffffff800a7823   <kernel_x86_64> stack_trace_trampoline(void*) + 0x09
 2 ffffffff8072db18 (+  24) ffffffff8013903c   <kernel_x86_64> arch_debug_call_with_fault_handler + 0x16
 3 ffffffff8072db30 (+  96) ffffffff800a820f   <kernel_x86_64> debug_call_with_fault_handler + 0x8b
 4 ffffffff8072db90 (+  96) ffffffff800a926b   <kernel_x86_64> kernel_debugger_loop(char const*, char const*, __va_list_tag*, int) + 0x10a
 5 ffffffff8072dbf0 (+  80) ffffffff800a96d4   <kernel_x86_64> kernel_debugger_internal(char const*, char const*, __va_list_tag*, int) + 0x1a2
 6 ffffffff8072dc40 (+ 240) ffffffff800a98d3   <kernel_x86_64> panic + 0xba
 7 ffffffff8072dd30 (+  64) ffffffff80113d6c   <kernel_x86_64> delete_object_cache_internal(ObjectCache*) + 0x67
 8 ffffffff8072dd70 (+  48) ffffffff80114e80   <kernel_x86_64> delete_object_cache + 0x169
 9 ffffffff8072dda0 (+  32) ffffffff80049634   <kernel_x86_64> _GLOBAL__N_1::block_cache::~block_cache(???, block_cache, Ev) + 0x62
10 ffffffff8072ddc0 (+  80) ffffffff8004f082   <kernel_x86_64> block_cache_delete + 0x322
11 ffffffff8072de10 (+  32) ffffffff8139d28a   <bfs> Volume::Unmount() + 0x8e
12 ffffffff8072de30 (+  32) ffffffff8139f944   <bfs> bfs_unmount(fs_volume*) + 0x13
13 ffffffff8072de50 (+ 128) ffffffff800f835f   <kernel_x86_64> fs_unmount(char*, int, unsigned int, bool) + 0x38b
14 ffffffff8072ded0 (+  80) ffffffff800fc884   <kernel_x86_64> _user_unmount + 0x7c
15 ffffffff8072df20 (+  16) ffffffff8013aae8   <kernel_x86_64> x86_64_syscall_entry + 0xfb
user iframe at 0xffffffff8072df30 (end = 0xffffffff8072dff8)
 rax 0x63                  rbx 0x0                   rcx 0x20922d412cc
 rdx 0x133214aa420         rsi 0x0                   rdi 0x1d14a88fe40
 rbp 0x7f54d2c74330         r8 0x0                    r9 0xd
 r10 0x20922d41609         r11 0x3246                r12 0x1d14a89ef80
 r13 0x0                   r14 0x1d14a8f0d6c         r15 0x7f54d2c74480
 rip 0x20922d412cc         rsp 0x7f54d2c74328     rflags 0x3246
 vector: 0x63, error code: 0x0
16 ffffffff8072df30 (+140004430210048) 0000020922d412cc   <libroot.so> _kern_unmount + 0x0c
17 00007f54d2c74330 (+ 208) 00000133211f02b0   <libbe.so> BPartition::Unmount(unsigned int) + 0x54
18 00007f54d2c74400 (+ 192) 000000b180c976d1   <_APP_> MountVisitor::Visit(BPartition*, int) + 0x487
19 00007f54d2c744c0 (+  16) 000000b180c96837   <_APP_> MountVisitor::Visit(BDiskDevice*) + 0x0f
20 00007f54d2c744d0 (+  32) 00000133211eb77f   <libbe.so> BPrivate::PartitionFilterVisitor::Visit(BDiskDevice*) + 0x33
21 00007f54d2c744f0 (+  16) 00000133211e873d   <libbe.so> BDiskDevice::_AcceptVisitor(BDiskDeviceVisitor*, int) + 0x13
22 00007f54d2c74500 (+  48) 00000133211eef7d   <libbe.so> BPartition::_VisitEachDescendant(BDiskDeviceVisitor*, int) + 0x27
23 00007f54d2c74530 (+  16) 00000133211eefdf   <libbe.so> BPartition::VisitEachDescendant const(BDiskDeviceVisitor*) + 0x13
24 00007f54d2c74540 (+  48) 00000133211eaa22   <libbe.so> BDiskDeviceList::VisitEachPartition(BDiskDeviceVisitor*) + 0x38
25 00007f54d2c74570 (+  80) 00000133211eab27   <libbe.so> BDiskDeviceList::VisitEachMountablePartition(BDiskDeviceVisitor*) + 0x37
26 00007f54d2c745c0 (+ 656) 000000b180c9622b   <_APP_> MountVolume::ArgvReceived(int, char**) + 0x527
27 00007f54d2c74850 (+  96) 00000133210daaf0   <libbe.so> BApplication::_ArgvReceived(BMessage*) + 0xa8
28 00007f54d2c748b0 (+ 576) 00000133210dd61f   <libbe.so> BApplication::DispatchMessage(BMessage*, BHandler*) + 0x12d
29 00007f54d2c74af0 (+  96) 00000133210e452e   <libbe.so> BLooper::task_looper() + 0x200
30 00007f54d2c74b50 (+  32) 00000133210da558   <libbe.so> BApplication::Run() + 0x46
31 00007f54d2c74b70 (+ 400) 000000b180c95984   <_APP_> main + 0x23
32 00007f54d2c74d00 (+  48) 000000b180c957ce   <_APP_> _start + 0x54
33 00007f54d2c74d30 (+  48) 0000015b497028a0   </boot/system/runtime_loader@0x0000015b496ef000> <unknown> + 0x138a0
34 00007f54d2c74d60 (+   0) 00007fff4850f260   <commpage> commpage_thread_exit + 0x00
kdebug> es