my setup was working as far as matrix is regarded. However I ran an apt upgrade and it tried to install the last version of matrixio-kernel-modules from 0.1.7 to 0.1.8. That failed and I couldn’t restore it in any way.
I purged the package as well as the raspberrypi-kernel-headers. Ran apt upgrade and there were - as expected - no more available packages. Then tried the matrix installation again, but it seems to fail for the same reason as the original update.
Does anybody have an idea?
pi@raspberrypi10:~ $ sudo apt install matrixio-kernel-modules Reading package lists... Done Building dependency tree Reading state information... Done The following additional packages will be installed: dkms raspberrypi-kernel-headers Suggested packages: python3-apport menu The following NEW packages will be installed: dkms matrixio-kernel-modules raspberrypi-kernel-headers 0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded. Need to get 16.7 MB/16.8 MB of archives. After this operation, 109 MB of additional disk space will be used. Do you want to continue? [Y/n] y Get:1 http://archive.raspberrypi.org/debian stretch/main armhf raspberrypi-kerne Fetched 16.7 MB in 12s (1,381 kB/s) Selecting previously unselected package dkms. (Reading database ... 46082 files and directories currently installed.) Preparing to unpack .../archives/dkms_2.3-2_all.deb ... Unpacking dkms (2.3-2) ... Selecting previously unselected package raspberrypi-kernel-headers. Preparing to unpack .../raspberrypi-kernel-headers_1.20190517-1_armhf.deb ... Unpacking raspberrypi-kernel-headers (1.20190517-1) ... Selecting previously unselected package matrixio-kernel-modules. Preparing to unpack .../matrixio-kernel-modules_0.1.8_armhf.deb ... Unpacking matrixio-kernel-modules (0.1.8) ... Setting up raspberrypi-kernel-headers (1.20190517-1) ... run-parts: executing /etc/kernel/header_postinst.d/dkms 4.19.42+ run-parts: executing /etc/kernel/header_postinst.d/dkms 4.19.42-v7+ Setting up dkms (2.3-2) ... Setting up matrixio-kernel-modules (0.1.8) ... Enabling firmware loading at startup Creating symlink /var/lib/dkms/matrixio/0.1/source -> /usr/src/matrixio-0.1 DKMS: add completed. Error! echo Your kernel headers for kernel 4.19.56-v7+ cannot be found at /lib/modules/4.19.56-v7+/build or /lib/modules/4.19.56-v7+/source. dpkg: error processing package matrixio-kernel-modules (--configure): subprocess installed post-installation script returned error exit status 1 Processing triggers for man-db (220.127.116.11-2) ... Errors were encountered while processing: matrixio-kernel-modules E: Sub-process /usr/bin/dpkg returned an error code (1) pi@raspberrypi10:~ $