On Tue, 4 Sep 2018, Daniel Vetter wrote: > On Tue, Sep 4, 2018 at 7:04 PM, Mikulas Patocka <mpatocka@xxxxxxxxxx> wrote: > > > > > > On Tue, 4 Sep 2018, Daniel Vetter wrote: > > > >> On Tue, Sep 4, 2018 at 1:41 AM, Dave Airlie <airlied@xxxxxxxxx> wrote: > >> >> > >> >> I've seen that you dropped this patch: > >> >> https://patchwork.kernel.org/patch/10445393/ > >> >> > >> >> Is that patch correct or incorrect? In case it is incorrect, do you have > >> >> an idea how should fbdefio be used properly on KMS drivers? > >> > > >> > I suppose I was wondering what use fbdefio really has, modern code > >> > should be using KMS interface and the KMS dirty handling should be > >> > able to cover those cases. > > > > I use fbdefio with the links 2 web browser and with fbi and fbgs image > > viewers. > > > > I tried to look into modifying the links browser to work without fbdefio - > > but the DRM_IOCTL_MODE_DIRTYFB ioctl requires master mode, which means > > that it is unuseable by an unprivileged process. If you suggest how should > > console applications use the framebuffer without fbdefio, I can implement > > it. > > Well with the console there's really no security. Either you disallow > touching fbdev, or everyone can read&write whatever they want, even if > they're not the currently active vt. So security just doesn't exist > with fbdev. I added myself to the video group, so that I can open /dev/fb0 and run graphics console applications. But I still can't set master mode, so I can't issue DRM_IOCTL_MODE_DIRTYFB to update the screen when fbdefio is turned off. > With kms you need logind or someone like that who orchestrates the vt > switching and makes sure you can read/write other people's stuff. The Links browser registers two signals via vt_mode.acqsig and vt_mode.relsig and repaints the screen or stops painting when they are received. If it should do something else - then what? It would be nice if the kms developers provided a simple graphics console application that describes how to use it. Mikulas _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
