On 03/05/2015 02:25 PM, walt wrote: > Downgrading Virtualbox to 4.3.20-r1 fixes the problem on one ~amd64 > machine but, of course, not the other one <sigh>.
For reasons I don't know, the gentoo devs split the "guest-additions" into two parts: they put the vboxvideo kernel module into the gentoo xf86-video-virtualbox package, and the vboxguest+vboxsf kernel modules into the virtualbox-guest-additions package. Anyway, starting with a vbox gentoo snapshot from Mar 3 (before the update to vbox-4.3.24) I upgraded only the virtualbox-guest-additions (not the xf86-video-virtualbox package) and found that everything still works normally. I then upgraded the xf86-video-virtualbox package and discovered that 3D video acceleration was broken, just as before. I then downgraded the xf86-video-virtualbox package to 4.3.20 (leaving the virtualbox-guest-additions at 4.3.24) and found the 3D acceleration working normally again. That clearly implicates the vboxvideo.ko kernel module as the cause of the breakage, I think. Opinions/comments are most welcome.
