One of the earliest pull requests sent in for the now-open Linux 5.15 cycle was proposing KSMBD land as the in-kernel SMB3 file server as an alternative on Linux systems to running Samba in user-space. At the time it wasn't clear if Linus Torvalds would pull in this file server code to the Linux kernel but now he has indeed landed it.

As noted in prior articles, KSMBD as developed by Samsung for some time now is focused on delivering speedy SMB3 file serving performance and also supporting features more implemented in kernel-space, like RDMA support for SMB Direct. KSMBD doesn't aim to be as comprehensive as well known Samba for CIFS/SMB support in user-space but is just focused on the performance and kernel feature angle.

KSMBD in its initial form is some 32k lines of new kernel code and is GPLv2 licensed.

A short time ago KSMBD was merged for Linux 5.15. More details on it via the documentation . Enabling KSMBD can be done via the CONFIG_SMB_SERVER Kconfig option.