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Re: Using wsdisplay from the Xserver

der Mouse wrote:
Can we run Xorg as unprivileged with this?
We already do on macppc and sparc(64), although arguably we probably
shouldn't allow mapping PCI resources without INSECURE.

Probably?  There's no `probably' about it, to me.  But then, I also
think the X server has no business mapping PCI resources, per se, at
all; it should be going through the display device's driver, which will
constrain what userland can map to what userland has business mapping -
and will do so regardless of the bus type; the X server also has no
business caring whether the display device is behind PCI, ISA, SBus,
Qbus, or something else.  That's what drivers are for: to insulate
userland from that mess.

Of course, this may be considered a heretical point of view.  But I
still maintain that moving a device driver's job into userland is a
very wrong thing to do in multiple respects.

This makes sense until you start to realize that graphics hardware has come a long way since cg14, and the amount of code required to support modern graphics hardware in the kernel would cause you to instead complain about bloat in the kernel.

And of course, when you're dealing with that much code, there are bound to be some bugs, and it's nice for it to not take the entire machine down when it falls over; even Microsoft has learned this lesson.

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