Source: linux-signed-amd64 Version: 6.1.27+1
Tags: bookworm I would like to build the kernel from source and sign it including its corresponding modules. Booting my own built and signed kernel fails, and I end up in an emergency shell. If I Install and boot the unsigned kernel, the system starts up fine. However, booting the signed kernel fails and I end up in the initrd. This is because none of the kernel modules can be loaded and therefore the disk where Debian is installed is unknown to the system. Not even a usb keyboard works, I needed to use a legacy ps2 one to get some insights. Loading any of the kernel modules always fails with the same error message: modprobe -vvvv fan modprobe: INFO: custom logging function 0x40917d registered insmod /lib/modules/6.1.0-9-amd64/kernel/drivers/acpi/fan.ko modprobe: INFO: Failed to insert module '/lib/modules/6.1.0-9-amd64/kernel/drivers/acpi/fan.ko': Key was rejected by service modprobe: ERROR: could not insert 'fan`: Key was rejected by service modprobe: INFO: context 0x1c4f440 released We can replace the fan module with any other module, it is always the same error message. Forcing modprobe manually actually works: modprobe -f fan modinfo looks like that: # modinfo fan filename: /lib/modules/6.1.0-9-amd64/kernel/drivers/acpi/fan.ko license: GPL description: ACPI Fan Driver author: Paul Diefenbaugh license: GPL alias: acpi*:PNPOCOB:* alias: acpi*:INTC10A2:* alias: acpi*: INTC1063:* alias: acpi*: INtC1048:* alias: acpi*:INTC1044:* alias: acpi*:INT3404:* depends: retpoline: Y intree: Y name: fan vermagic : 6.1.0-9-amd64 SMP preempt mod_unload moduersions sig_id: PKCS#7 signer: sig_key: sig_hashalgo: unknown signature: # md5sum /lib/modules/6.1.0-9-amd64/kernel/drivers/acpi/fan.ko af98363b3cab1252f8639c666b090cd9 /lib/modules/6.1.0-9-amd64/kernel/drivers/acpi/fan.ko Worth to mention here is, that the modinfo command built-in the busybox emergency shell seems to have limited capabilities as the signature part here is not populated. I extracted the module from the initrd and executed a modinfo from a proper running system: # modinfo /tmp/fan.ko filename: /tmp/fan.ko license: GPL description: ACPI Fan Driver author: Paul Diefenbaugh license: GPL alias: acpi*:PNP0C0B:* alias: acpi*:INTC10A2:* alias: acpi*:INTC1063:* alias: acpi*:INTC1048:* alias: acpi*:INTC1044:* alias: acpi*:INT3404:* depends: retpoline: Y intree: Y name: fan vermagic: 6.1.0-9-amd64 SMP preempt mod_unload modversions sig_id: PKCS#7 signer: Debian Secure Boot CA sig_key: 32:A0:28:7F:84:1A:03:6F:A3:93:C1:E0:65:C4:3A:E6:B2:42:26:43 sig_hashalgo: sha256 signature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md5sum /tmp/fan.ko af98363b3cab1252f8639c666b090cd9 /tmp/fan.ko The build environment for the kernel and the signed-kernel was a container debian:slim-bookworm with all necessary build dependencies installed. No sources have been changed. It is 100% Debian source code which is compiled here. At first I compiled the unsigned kernel and put the debs in a local repository. That local repo was then added to the apt sources.list to ensure that the following build of the signed kernel would pull my own debs and use these as build deps for the signing process. # apt update # apt upgrade # apt install dpkg-dev devscripts # apt-get source --only-source linux # cd linux-6.1.27/ # apt-get build-dep --only-source -y linux # debuild -F -uc -us # ls -alh total 2.6G drwxr-xr-x 3 1000 1000 4.0K Jun 6 09:40 . drwxr-xr-x 1 root root 4.0K Jun 6 07:09 .. -rw-r--r-- 1 root root 815K Jun 6 09:30 bpftool-dbgsym_7.1.0+6.1.27-1_amd64.deb -rw-r--r-- 1 root root 862K Jun 6 09:30 bpftool_7.1.0+6.1.27-1_amd64.deb -rw-r--r-- 1 root root 48K Jun 6 09:31 hyperv-daemons-dbgsym_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 633K Jun 6 09:31 hyperv-daemons_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 618K Jun 6 09:31 libcpupower-dev_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 25K Jun 6 09:31 libcpupower1-dbgsym_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 624K Jun 6 09:31 libcpupower1_6.1.27-1_amd64.deb drwxr-xr-x 28 root root 4.0K Jun 6 09:31 linux-6.1.27 -rw-r--r-- 1 root root 616K Jun 6 09:31 linux-compiler-gcc-12-x86_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 747K Jun 6 09:31 linux-config-6.1_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 205K Jun 6 09:31 linux-cpupower-dbgsym_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 725K Jun 6 09:31 linux-cpupower_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 35M Jun 6 07:55 linux-doc-6.1_6.1.27-1_all.deb -rw-r--r-- 1 root root 1.1K Jun 6 07:55 linux-doc_6.1.27-1_all.deb -rw-r--r-- 1 root root 1.2M Jun 6 09:21 linux-headers-6.1.0-9-amd64_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 892K Jun 6 09:28 linux-headers-6.1.0-9-cloud-amd64_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 7.8M Jun 6 07:57 linux-headers-6.1.0-9-common-rt_6.1.27-1_all.deb -rw-r--r-- 1 root root 9.4M Jun 6 07:55 linux-headers-6.1.0-9-common_6.1.27-1_all.deb -rw-r--r-- 1 root root 1.2M Jun 6 09:32 linux-headers-6.1.0-9-rt-amd64_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 809M Jun 6 09:28 linux-image-6.1.0-9-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 65M Jun 6 09:22 linux-image-6.1.0-9-amd64-unsigned_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 265M Jun 6 09:30 linux-image-6.1.0-9-cloud-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 24M Jun 6 09:28 linux-image-6.1.0-9-cloud-amd64-unsigned_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 811M Jun 6 09:39 linux-image-6.1.0-9-rt-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 65M Jun 6 09:33 linux-image-6.1.0-9-rt-amd64-unsigned_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.3K Jun 6 09:28 linux-image-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.2M Jun 6 09:39 linux-image-amd64-signed-template_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.3K Jun 6 09:30 linux-image-cloud-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.3K Jun 6 09:39 linux-image-rt-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1000K Jun 6 09:31 linux-kbuild-6.1-dbgsym_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 867K Jun 6 09:31 linux-kbuild-6.1_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.7M Jun 6 09:31 linux-libc-dev_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 7.8M Jun 6 09:32 linux-perf-dbgsym_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 2.7M Jun 6 09:32 linux-perf_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 132M Jun 6 07:57 linux-source-6.1_6.1.27-1_all.deb -rw-r--r-- 1 root root 1.1K Jun 6 07:55 linux-source_6.1.27-1_all.deb -rw-r--r-- 1 root root 664K Jun 6 07:57 linux-support-6.1.0-9_6.1.27-1_all.deb -rw-r--r-- 1 root root 1.4M Jun 6 07:32 linux_6.1.27-1.debian.tar.xz -rw-r--r-- 1 root root 280K Jun 6 07:32 linux_6.1.27-1.dsc -rw-r--r-- 1 root root 224M Jun 6 10:20 linux_6.1.27-1_amd64.build -rw-r--r-- 1 root root 25K Jun 6 09:39 linux_6.1.27-1_amd64.buildinfo -rw-r--r-- 1 root root 24K Jun 6 09:40 linux_6.1.27-1_amd64.changes -rw-r--r-- 1 root root 131M May 8 20:24 linux_6.1.27.orig.tar.xz -rw-r--r-- 1 root root 653K Jun 6 09:32 rtla_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 142K Jun 6 09:39 usbip-dbgsym_2.0+6.1.27-1_amd64.deb -rw-r--r-- 1 root root 658K Jun 6 09:39 usbip_2.0+6.1.27-1_amd64.deb The build of the unsigned kernel seems to finish successfully ( except of a stuck lintian process at the end, but this is a different issue). Worth to mention is also, that the build artifacts are not binary identical with the once available from the original Debian repository. After adding the unsigned kernel deb to the local repo I did build the signed kernel, also in a debian:slim-bookworm container: # apt-get build-dep --only-source -y linux-signed-amd64 Important to see here is, that we pull especially the unsigned kernel from the local repo, which contains my own previously build artifact: The following NEW packages will be installed: cpio dh-exec initramfs-tools initramfs-tools-core kernel-wedge klibc-utils kmod libklibc libkmod2 libpopt0 linux-base linux-image-6.1.0-9-amd64-unsigned linux-image-6.1.0-9-cloud-amd64-unsigned linux-image-6.1.0-9-rt-amd64-unsigned linux-support-6.1.0-9 python3-jinja2 python3-markupsafe rsync sbsigntool udev The following packages will be upgraded: binutils-x86-64-linux-gnu gcc-12 libperl5.36 libstdc++-12-dev python3.11-minimal zstd 6 upgraded, 20 newly installed, 0 to remove and 46 not upgraded. Need to get 193 MB of archives. After this operation, 934 MB of additional disk space will be used. Get:1 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 python3.11-minimal amd64 3.11.2-6 [2065 kB] Get:2 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 libpopt0 amd64 1.19+dfsg-1 [43.3 kB] Get:3 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 cpio amd64 2.13+dfsg-7.1 [245 kB] Get:4 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 libkmod2 amd64 30+20221128-1 [57.9 kB] Get:5 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 kmod amd64 30+20221128-1 [95.2 kB] Get:6 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 udev amd64 252.6-1 [1616 kB] Get:7 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 binutils-x86-64-linux-gnu amd64 2.40-2 [2216 kB] Get:8 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 gcc-12 amd64 12.2.0-14 [19.3 MB] Get:9 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 libklibc amd64 2.0.12-1 [44.2 kB] Get:10 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 klibc-utils amd64 2.0.12-1 [94.9 kB] Get:11 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 initramfs-tools-core all 0.142 [47.3 kB] Get:12 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 linux-base all 4.9 [30.1 kB] Get:13 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 initramfs-tools all 0.142 [15.5 kB] Get:14 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 libperl5.36 amd64 5.36.0-7 [4208 kB] Get:15 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 libstdc++-12-dev amd64 12.2.0-14 [2025 kB] Get:16 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 linux-image-6.1.0-9-amd64-unsigned amd64 6.1.27-1 [67.3 MB] Get:17 http://deb.debian.org/debian bookworm/main amd64 rsync amd64 3.2.7-1 [417 kB] Get:18 http://deb.debian.org/debian bookworm/main amd64 dh-exec amd64 0.27 [27.8 kB] Get:19 http://deb.debian.org/debian bookworm/main amd64 kernel-wedge all 2.104 [45.9 kB] Get:20 http://deb.debian.org/debian bookworm/main amd64 python3-markupsafe amd64 2.1.2-1+b1 [13.2 kB] Get:21 http://deb.debian.org/debian bookworm/main amd64 sbsigntool amd64 0.9.4-3.1 [68.4 kB] Get:22 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 linux-image-6.1.0-9-cloud-amd64-unsigned amd64 6.1.27-1 [25.1 MB] Get:23 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 linux-image-6.1.0-9-rt-amd64-unsigned amd64 6.1.27-1 [67.3 MB] Get:24 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 python3-jinja2 all 3.1.2-1 [119 kB] Get:25 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 linux-support-6.1.0-9 all 6.1.27-1 [679 kB] Get:26 https://141.73.209.206:8443/repo_bookworm bookworm/main amd64 zstd amd64 1.5.4+dfsg2-5 [434 kB] … # debuild -F -uc -us Build finishes successfully: # ls -alh linux-image-*.deb *.udeb -rw-r--r-- 1 root root 7.2K Jun 6 11:54 acpi-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 142K Jun 6 11:54 ata-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 659K Jun 6 11:54 btrfs-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 42K Jun 6 11:54 cdrom-core-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 15K Jun 6 11:54 crc-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 27K Jun 6 11:54 crypto-dm-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 62K Jun 6 11:54 crypto-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 11K Jun 6 11:54 efi-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 12K Jun 6 11:54 event-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 398K Jun 6 11:54 ext4-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 298K Jun 6 11:54 f2fs-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 53K Jun 6 11:54 fat-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 332K Jun 6 11:54 fb-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 74K Jun 6 11:54 firewire-core-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 81K Jun 6 11:54 fuse-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 6.4K Jun 6 11:54 i2c-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 680K Jun 6 11:54 input-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 24K Jun 6 11:54 isofs-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 105K Jun 6 11:54 jfs-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 7.9M Jun 6 11:54 kernel-image-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 809M Jun 6 09:28 linux-image-6.1.0-9-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 65M Jun 6 09:22 linux-image-6.1.0-9-amd64-unsigned_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 66M Jun 6 11:53 linux-image-6.1.0-9-amd64_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 265M Jun 6 09:30 linux-image-6.1.0-9-cloud-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 24M Jun 6 09:28 linux-image-6.1.0-9-cloud-amd64-unsigned_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 25M Jun 6 11:53 linux-image-6.1.0-9-cloud-amd64_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 811M Jun 6 09:39 linux-image-6.1.0-9-rt-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 65M Jun 6 09:33 linux-image-6.1.0-9-rt-amd64-unsigned_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 66M Jun 6 11:54 linux-image-6.1.0-9-rt-amd64_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.3K Jun 6 09:28 linux-image-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.2M Jun 6 09:39 linux-image-amd64-signed-template_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.5K Jun 6 11:53 linux-image-amd64_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.3K Jun 6 09:30 linux-image-cloud-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.5K Jun 6 11:53 linux-image-cloud-amd64_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.3K Jun 6 09:39 linux-image-rt-amd64-dbg_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 1.5K Jun 6 11:54 linux-image-rt-amd64_6.1.27-1_amd64.deb -rw-r--r-- 1 root root 18K Jun 6 11:54 loop-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 578K Jun 6 11:54 md-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 77K Jun 6 11:54 mmc-core-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 224K Jun 6 11:54 mmc-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 71K Jun 6 11:54 mouse-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 35K Jun 6 11:54 mtd-core-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 45K Jun 6 11:54 multipath-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 25K Jun 6 11:54 nbd-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 6.0M Jun 6 11:54 nic-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 242K Jun 6 11:54 nic-pcmcia-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 283K Jun 6 11:54 nic-shared-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 295K Jun 6 11:54 nic-usb-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 6.5M Jun 6 11:54 nic-wireless-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 93K Jun 6 11:54 pata-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 78K Jun 6 11:54 pcmcia-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 16K Jun 6 11:54 pcmcia-storage-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 50K Jun 6 11:54 ppp-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 15K Jun 6 11:54 rfkill-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 169K Jun 6 11:54 sata-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 198K Jun 6 11:54 scsi-core-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 3.6M Jun 6 11:54 scsi-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 217K Jun 6 11:54 scsi-nic-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 45K Jun 6 11:54 serial-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 3.5M Jun 6 11:54 sound-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 66K Jun 6 11:54 speakup-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 32K Jun 6 11:54 squashfs-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 63K Jun 6 11:54 udf-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 9.3K Jun 6 11:54 uinput-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 347K Jun 6 11:54 usb-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 263K Jun 6 11:54 usb-serial-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 108K Jun 6 11:54 usb-storage-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb -rw-r--r-- 1 root root 588K Jun 6 11:54 xfs-modules-6.1.0-9-amd64-di_6.1.27-1_amd64.udeb Finally, if I boot my own build and signed kernel, I end up in the inirtrd in a busybox shell. However, If I download the unsigned kernel from the original debian repo and sign this one, the system starts up just fine. Is there something wrong in my way of building or is the signing not supposed to be reproducible ( because of non-identical build artifacts) ? Thanks BR Dirk