Package: src:linux Version: 6.0.8-1 Severity: wishlist It has been 6 years (since Linux kernel v4.10) that upstream introduced a rather useful feature for protocols implementing binary message based protocols on top of TCP called KCM. Unfortunately during all those years and even until Debian unstable today, it is not possible to use this feature as the kernels are compiled with CONFIG_AF_KCM disabled.
This creates a rather unfortunate chicken-and-egg situation where there are userspace programs/libraries that would benefit from its related performance, but cannot use it with unmodified Debian kernels and hence are less motivated to enable it. So lack of distribution support hinders adoption by more applications. Background on KCM can be found at https://lwn.net/Articles/657999/ and in the kernel source at Documentation/networking/kcm.rst I would hence like to request enabling CONFIG_AF_KCM in the Debian kernel packages. Since STREAM_PARSER and BPF_SYSCALL are both already enabled, there are no additional dependencies. AF_KCM can be built as module, so it should not affect any systems where no applications use it. It would only be auto-loaded once an AF_KCM socket is being used for the first time. Thanks for your consideration. -- Package-specific info: ** Kernel log: boot messages should be attached -- System Information: Debian Release: bookworm/sid APT prefers unstable-debug APT policy: (500, 'unstable-debug'), (500, 'unstable') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 5.19.0-2-amd64 (SMP w/4 CPU threads; PREEMPT) Kernel taint flags: TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE Locale: LANG=en_US.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8), LANGUAGE not set Shell: /bin/sh linked to /usr/bin/dash Init: systemd (via /run/systemd/system) LSM: AppArmor: enabled Versions of packages linux-image-6.0.0-4-amd64 depends on: it initramfs-tools [linux-initramfs-tool] 0.142 ii kmod 30+20220905-1 ii linux-base 4.9 Versions of packages linux-image-6.0.0-4-amd64 recommends: iu apparmor 3.0.7-1+b2 ii firmware-linux-free 20200122-1 Versions of packages linux-image-6.0.0-4-amd64 suggests: pn debian-kernel-handbook <none> ii extlinux 3:6.04~git20190206.bf6db5b4+dfsg1-3+b1 ii grub-pc 2.06-4 pn linux-doc-6.0 <none> Versions of packages linux-image-6.0.0-4-amd64 is related to: pn firmware-amd-graphics <none> pn firmware-atheros <none> pn firmware-bnx2 <none> pn firmware-bnx2x <none> pn firmware-brcm80211 <none> pn firmware-cavium <none> pn firmware-intel-sound <none> pn firmware-intelwimax <none> pn firmware-ipw2x00 <none> pn firmware-ivtv <none> ii firmware-iwlwifi 20221012-1 pn firmware-libertas <none> pn firmware-linux-nonfree <none> ii firmware-misc-nonfree 20221012-1 pn firmware-myricom <none> pn firmware-netxen <none> pn firmware-qlogic <none> pn firmware-realtek <none> pn firmware-samsung <none> pn firmware-siano <none> pn firmware-ti-connectivity <none> pn xen-hypervisor <none> -- no debconf information