Like the last line suggested, that's harmless if your linux box has no secureboot enabled currently. If so, you need to enroll your own key in BIOS, and use it to sign your own build of kernel modules. See https://wiki.ubuntu.com/UEFI/SecureBoot/DKMS.
** Changed in: linux (Ubuntu) Status: Incomplete => Invalid -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1902083 Title: v4l2loopback Status in linux package in Ubuntu: Invalid Bug description: make && sudo make install Building v4l2-loopback driver... make -C /lib/modules/`uname -r`/build M=/home/rama/Downloads/VirtualWebcam/v4l2loopback modules make[1]: Entering directory '/usr/src/linux-headers-5.8.0-25-generic' make[1]: Leaving directory '/usr/src/linux-headers-5.8.0-25-generic' make -C /lib/modules/`uname -r`/build M=/home/rama/Downloads/VirtualWebcam/v4l2loopback modules_install make[1]: Entering directory '/usr/src/linux-headers-5.8.0-25-generic' INSTALL /home/rama/Downloads/VirtualWebcam/v4l2loopback/v4l2loopback.ko At main.c:160: - SSL error:02001002:system library:fopen:No such file or directory: ../crypto/bio/bss_file.c:69 - SSL error:2006D080:BIO routines:BIO_new_file:no such file: ../crypto/bio/bss_file.c:76 sign-file: certs/signing_key.pem: No such file or directory DEPMOD 5.8.0-25-generic Warning: modules_install: missing 'System.map' file. Skipping depmod. make[1]: Leaving directory '/usr/src/linux-headers-5.8.0-25-generic' SUCCESS (if you got 'SSL errors' above, you can safely ignore them) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1902083/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp