User-space device drivers

Posted Jan 30, 2004 14:20 UTC (Fri) by forthy (guest, #1525)
Parent article: User-space device drivers

The interrupt delivery part is something that has been necessary for years, because X still can't give you any way to syncronize to VBL interrupts (except OpenGL).

On the other hand, I don't feel too happy with user land directly accessing IO ports. This is still dangerous, and buggy X drivers often can hang the machine, too. Memory mapped IO pages should be ok, given that the kernel would allow to map the PCI memory per device, not from /dev/mem. I suggets to keep the IO port part of a device driver inside kernel space.