On Sun, 13 Jan 2002, Dr Andrew C Aitchison wrote: > You can use drivers like fbdev, in which case I believe dga can (perhaps > this is still theoretical) use /dev/fbdev instead of /dev/mem, and not > need SUID root.
Yes, and someone else (Mark V?) was saying that this could be easily done with DGA instead of using /dev/mem, if framebuffer devices were more universally available. > The other reason that dga is not a good idea is : > "Why should XFree86 provide a mechanism for direct framebuffer access anyway ?" > If the app isn't interested in using the X protocol to drive the screen > (and DRI and XV show that that can be plenty fast enough), the app should > just chvt to a free virtual terminal and use svgalib instead. Because yes, then you get access to the framebuffer, but then that's one more library that has to be maintained for (mainly initialization) supporting the different boards out there. Is anyone even maintaining SVGAlib anymore? And SVGAlib still doesn't avert the whole SUID root issue. Fact is, once a program starts using DGA, and gets access to the framebuffer, from its perspective one video card works the same as another. That's the advantage of DGA. Unfortunately, as you mentioned, the SUID root thing is a serious downside. > Games developers need big control over their machines, and must surely > be trusted with the machine ? Perhaps making /dev/mem group writable > by the user of each machine might be sensible in that sort of restricted > environment ? I really doubt that anyone's going to be playing a 2D sidescroller on a multiuser system, physically at the console. It'd probably be (a) a home box, in which case, they have root and can install it themselves, or (b) it's probably a workstation/lab type scenario, and stuff like that shouldn't be running on a machine like that anyhow. Of course, with most modern game titles aiming toward 3D hardware (OpenGL on Linux, OGL/D3D on Win32), Linux 3D game titles just use DRI outright, which doesn't require that nasty SUID bit at all. Derrik Pates | Sysadmin, Douglas School | #linuxOS on EFnet [EMAIL PROTECTED] | District (dsdk12.net) | #linuxOS on OPN _______________________________________________ Xpert mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xpert
