The Bochs Direct Rendering Manager (DRM) kernel driver is currently being modernized. The Bochs driver is important in that it is often used for virtual VGA output with QEMU for Linux virtualization.
Thomas Zimmermann of SUSE, who has done excellent work on Linux’s upstream DRM code, has taken on improving the state of the Bochs driver and bringing it up to date.
The new patch series released today removes features from the Bochs DRM driver code that have since appeared in the DRM core itself, reworks EDID processing to comply with current best practices, replaces simple display helpers with atomic helpers, and makes other improvements.
The biggest impact for end users is the replacement of GEM VRAM with GEM SHMEM, as the new memory manager is more reliable and allows higher resolutions with this new memory management code. Thomas Zimmermann explained the use of GEM SHMEM for Bochs:
“Patch 8 replaces GEM VRAM with GEM SHMEM. The new memory manager is more reliable and allows higher resolutions. Display updates were so slow that Gnome was unmanageable with a flickering cursor and single FPS. The new memory management at least makes Gnome usable.”
So a nice step forward for everyone who wants to use Bochs’ virtual VGA output with QEMU and operate a modern output.
If you use the Bochs DRM driver, you can currently find the patches on the Linux DRI mailing list.
