#1146689 displaylink-driver: DisplayLinkManager fails without libevdi-dev on Trixie

Package:
displaylink-driver
Source:
displaylink-driver
Submitter:
Nedyalko Tenev
Date:
2026-09-04 11:57:02 UTC
Severity:
normal
#1146689#5
Date:
2026-09-04 11:52:40 UTC
From:
To:
Dear Maintainer,

On Debian 13 Trixie, displaylink-driver 6.1-2 fails to provide video output on
my Lenovo ThinkPad Hybrid USB-C with USB-A Dock (40AF).

The dock itself is detected correctly, power, Ethernet and USB works, the evdi
kernel module loads successfully, and displaylink-driver.service is active.
However, DisplayLinkManager doesn't attach to the EVDI DRM devices and
DisplayPort & HDMI don't output anything.

Running DisplayLinkManager under strace showed that version 6.1-2 attempts to
load the unversioned library "libevdi.so":

    openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libevdi.so", O_RDONLY|O_CLOEXEC) =
-1 ENOENT (No such file or directory)
    openat(AT_FDCWD, "/usr/lib/x86_64-linux-gnu/libevdi.so",
O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
    openat(AT_FDCWD, "/usr/lib/libevdi.so", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No
such file or directory)

Installing libevdi-dev provides the missing symlink:

    $ dpkg -S /usr/lib/libevdi.so
    libevdi-dev: /usr/lib/libevdi.so

    $ ls -l /usr/lib/libevdi.so*
    /usr/lib/libevdi.so -> libevdi.so.1
    /usr/lib/libevdi.so.1 -> libevdi.so.1.14.8
    /usr/lib/libevdi.so.1.14.8

After installing libevdi-dev and restarting, DisplayLink video output works
correctly.

I also tested Debian's displaylink-driver 6.3-1. The issue is fixed (i think)
there: strace shows DisplayLinkManager loading libevdi.so.1 successfully
instead of attempting to load libevdi.so:

    openat(AT_FDCWD, "/lib/libevdi.so.1", O_RDONLY|O_CLOEXEC) = 10

Regards,
Nedyalko Tenev