USB-4 / Thunderbolt cable between two Framework Laptops

Has anyone successfully connected two Framework 16 laptops to each other via the USB4 / Thunderbolt ports?

When I connect them, I get the following errors in dmesg, regardless of the cable I put between them :

[  x.y] ucsi_acpi USBC000:00: unknown error 0
[  x.y] ucsi_acpi USBC000:00: GET_CABLE_PROPERTY failed (-5)

Keen for any approach that might work, I’ve tried various cables.

Which Linux distro are you using?

Bluefin / Ublue

Which release version?

> lsb-release -a
LSB Version:	n/a
Distributor ID:	Bluefin
Description:	Bluefin (Version: latest-42.20250924.1)
Release:	42
Codename:	Deinonychus

Which kernel are you using?

> uname -a
Linux framey 6.16.7-200.fc42.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Sep 11 17:46:54 UTC 2025 x86_64 GNU/Linux

Which BIOS version are you using?

> sudo dmidecode -t bios
# dmidecode 3.6

Getting SMBIOS data from sysfs.
SMBIOS 3.6.0 present.

Handle 0x0000, DMI type 0, 26 bytes
BIOS Information
Vendor: INSYDE Corp.
Version: 03.03
Release Date: 03/27/2024
Address: 0xE0000
Runtime Size: 128 kB
ROM Size: 32 MB
Characteristics:
PCI is supported
BIOS is upgradeable
BIOS shadowing is allowed
Boot from CD is supported
Selectable boot is supported
8042 keyboard services are supported (int 9h)
CGA/mono video services are supported (int 10h)
ACPI is supported
USB legacy is supported
BIOS boot specification is supported
Targeted content distribution is supported
UEFI is supported
BIOS Revision: 3.3

Which Framework Laptop 16 model are you using? (AMD Ryzen™ 7040 Series)

7040 Series

That message shouldn’t prevent thunderbolt networking from working.

You should just need to load the kernel module on both ends (thunderbolt_net)

My favorite red herring, I do wish they’d fix that at some point.