The RISC-V code in Linux 6.0 improves its Svpbmt support, which is the RISC-V extension for Page-Based Memory Types. Svpbmt has been worked on for the Linux kernel since earlier in the year with this extension defining behavior around non-cacheable pages, I/O memory pages, etc. Svpbmt was added in Linux 5.19 and now further improved upon for the 6.0 cycle.
The Linux 6.0 RISC-V changes also include a more useful default configuration "defconfig" . The Linux 6.0 RISC-V defconfig now enables enough features out-of-the-box that Docker can be run without issues. Additionally, more of the kernel features needed for Ubuntu's Snaps are also present. That earlier article has more details on the particular kernel features now flipped on for the RISC-V defconfig.
Other RISC-V patches for Linux 6.0 include CPU topology bindings for a few more systems, support for systems with 64-bit hart IDs, and other clean-ups and improvements.
All the details on the RISC-V code churn for Linux 6.0 via this pull request that has already landed in master.