I have the same problem in Windows Subsystem for Linux, Ubuntu 20.04 
I have a CIFS share containing 24 DFS folders.
Opening any subfolder in the share causes an instant kernel panic.
I do not have this problem on embedded hardware reading from the same share running the xilinx 4.6.0 kernel and 16.04LTS derivative (Petalinux 2016).


'Virtual Machine' has encountered a fatal error.  The guest operating system reported that it failed with the following error codes: ErrorCode0: 0x0, ErrorCode1: 0x0, ErrorCode2: 0x0, ErrorCode3: 0x0, ErrorCode4: 0x0.  If the problem persists, contact Product Support for the guest operating system.  (Virtual machine ID 2AE8F1B1-E89F-426B-867C-E089D530D127)

Guest message:
[ 5664.306032] CR2: ffffffffffffffd6 CR3: 00000001844ee004 CR4: 00000000003706a0
[ 5664.306033] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 5664.306035] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 5664.306036] Call Trace:
[ 5664.306549]  __traverse_mounts+0x8f/0x220
[ 5664.306885]  step_into+0x430/0x6c0
[ 5664.307085]  ? cifs_d_revalidate+0x49/0xd0
[ 5664.307088]  walk_component+0x72/0x1b0
[ 5664.307107]  path_lookupat.isra.0+0x6e/0x150
[ 5664.307109]  ? cifs_revalidate_dentry_attr+0x3f/0x230
[ 5664.307111]  filename_lookup+0xae/0x140
[ 5664.307157]  ? __check_object_size+0x136/0x150
[ 5664.307337]  ? strncpy_from_user+0x4e/0x140
[ 5664.307340]  __x64_sys_chdir+0x3e/0xe0
[ 5664.307621]  do_syscall_64+0x33/0x80
[ 5664.307846]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 5664.307906] RIP: 0033:0x7f03cf10ba1b
[ 5664.307908] Code: c3 48 8b 15 77 d4 0d 00 f7 d8 64 89 02 b8 ff ff ff ff eb c6 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 50 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 45 d4 0d 00 f7 d8 64 89 01 48
[ 5664.307911] RSP: 002b:00007ffdfac2d908 EFLAGS: 00000246 ORIG_RAX: 0000000000000050
[ 5664.307913] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f03cf10ba1b
[ 5664.307914] RDX: 0000561b7d79f360 RSI: 0000561b7d88e310 RDI: 0000561b7d892df0
[ 5664.307915] RBP: 0000561b7d892df0 R08: 0000000000000003 R09: 0000000000000001
[ 5664.307917] R10: 0000000000000000 R11: 0000000000000246 R12: 0000561b7d98e1d0
[ 5664.307918] R13: 0000000000000000 R14: 000000000000000a R15: 0000000000000000
[ 5664.307982] Modules linked in:
[ 5664.308086] CR2: 0000000000000000
[ 5664.308088] ---[ end trace d8722f6ff345c4cf ]---
[ 5664.308289] RIP: 0010:0x0
[ 5664.308291] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[ 5664.308292] RSP: 0018:ffffc90002b8bca0 EFLAGS: 00010293
[ 5664.308312] RAX: 0000000000000000 RBX: ffffc90002b8bd10 RCX: 0000000000000001
[ 5664.308314] RDX: 0000000000000000 RSI: 0000000000020000 RDI: ffffc90002b8bd10
[ 5664.308316] RBP: ffffc90002b8be40 R08: 0000000000000002 R09: 0000000000000064
[ 5664.308317] R10: ffff8883e1b9ba80 R11: 432f6b6300000061 R12: 0000000000000002
[ 5664.308318] R13: 0000000000000000 R14: 00000000002a0044 R15: 0000000000000000
[ 5664.308320] FS:  00007f03ceffa740(0000) GS:ffff8883f7d00000(0000) knlGS:0000000000000000
[ 5664.308322] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 5664.308323] CR2: ffffffffffffffd6 CR3: 00000001844ee004 CR4: 00000000003706a0
[ 5664.308325] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 5664.308326] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 5664.308327] Kernel panic - not syncing: Fatal exception