Linux Frame-Buffer Console To Drop Accelerated Scrolling Since It's Full Of Bugs
The Linux kernel's frame-buffer console (FBCON) is set to drop accelerated scrolling support since it isn't widely used and now found to be "full of bugs" plaguing the code-base.
Google's Syzbot that continuously fuzzes the Linux kernel using Syzkaller recently began fuzzing the FBCON code within the kernel. As a result of that exposure, the developers are now well aware with "solid proof that it's full of bugs."
The best solution from the developer perspective has been to delete the code / faulty features, such as with the recent deleting of soft scrollback support. Given the use-cases for FBCON and only a few drivers supporting accelerated scrolling, it's the latest feature now slated for removal.
Nouveau is the main DRM driver that supports FBCON accelerated scrolling while OMAPDRM and GMA500 also support accelerated support in some conditions. But the other drivers are not offering any accelerated FBCON support.
As such, open-source Intel Linux developer Daniel Vetter who is also a DRM co-maintainer proposed dropping the accelerated scrolling support from the kernel.
Vetter submitted a patch that initially disables the acceleration code within FBCON. Ultimately though the plan is to delete the code in which case "we could garbage collect fairly enormous amounts of code if we kill this," in dropping the accelerated scrolling code completely.
Following initial discussions it looks like this change could happen for Linux 5.11 where Nouveau / OMAPDRM / GMA500 would be affected and resort to always redrawing the console when scrolling. Approximately one year after merging would be when they plan to actually delete all of the then useless code.
Google's Syzbot that continuously fuzzes the Linux kernel using Syzkaller recently began fuzzing the FBCON code within the kernel. As a result of that exposure, the developers are now well aware with "solid proof that it's full of bugs."
The best solution from the developer perspective has been to delete the code / faulty features, such as with the recent deleting of soft scrollback support. Given the use-cases for FBCON and only a few drivers supporting accelerated scrolling, it's the latest feature now slated for removal.
Nouveau is the main DRM driver that supports FBCON accelerated scrolling while OMAPDRM and GMA500 also support accelerated support in some conditions. But the other drivers are not offering any accelerated FBCON support.
As such, open-source Intel Linux developer Daniel Vetter who is also a DRM co-maintainer proposed dropping the accelerated scrolling support from the kernel.
Vetter submitted a patch that initially disables the acceleration code within FBCON. Ultimately though the plan is to delete the code in which case "we could garbage collect fairly enormous amounts of code if we kill this," in dropping the accelerated scrolling code completely.
Following initial discussions it looks like this change could happen for Linux 5.11 where Nouveau / OMAPDRM / GMA500 would be affected and resort to always redrawing the console when scrolling. Approximately one year after merging would be when they plan to actually delete all of the then useless code.
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