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It's hybrid indeed, but far more modular. The driver code is running in kernel mode to avoid costly switching from kernel to user mode and back. This imposed re

It's hybrid indeed, but far more modular. The driver code is running in kernel mode to avoid costly switching from kernel to user mode and back. This imposed requirements on driver code quality as it is critical for the entire system, but it can be replaced (with another version) as a component. For a monolithic kernel like Linux changing a driver like the one for video card means recompiling the entire thing.

gh02t 11y ago
> For a monolithic kernel like Linux changing a driver like the one for video card means recompiling the entire thing. Not necessarily, Linux has loadable kernel modules as well and most drivers are built that way and loaded on demand. The Nvidia proprietary drivers for instance are a loadable kernel module, though they are tied to a specific kernel version. BSD does basically the same thing.
- creshal 11y ago
  There are somewhat more subtle differences: Not only are modules not tied to a particular kernel, they are also (to varying degrees) isolated against the rest of the kernel. WDDM in particular can recover from a driver crash and restart hardware and driver (which you can trivially demonstrate on an AMD card by waiting for an hour or two…), while Linux (and Windows XP with its older driver model, and probably BSDs) will panic the entire kernel on problems like this.
  - gh02t 11y ago
    Yeah, that's what I thought with NT, which is that drivers are much more isolated. If I understand it correctly drivers can still cause a kernel panic, but Microsoft requires that signed drivers pass a formal verification, which has greatly cut down on blue screens. I'm just an armchair observer though, so I'm not an expert. I was always greatly impressed by Windows' recent ability to recover from something like a display driver crash with hardly a hiccup. That's pretty impressive voodoo.

gh02t 11y ago

> For a monolithic kernel like Linux changing a driver like the one for video card means recompiling the entire thing. Not necessarily, Linux has loadable kernel modules as well and most drivers are built that way and loaded on demand. The Nvidia proprietary drivers for instance are a loadable kernel module, though they are tied to a specific kernel version. BSD does basically the same thing.

creshal 11y ago
There are somewhat more subtle differences: Not only are modules not tied to a particular kernel, they are also (to varying degrees) isolated against the rest of the kernel. WDDM in particular can recover from a driver crash and restart hardware and driver (which you can trivially demonstrate on an AMD card by waiting for an hour or two…), while Linux (and Windows XP with its older driver model, and probably BSDs) will panic the entire kernel on problems like this.
- gh02t 11y ago
  Yeah, that's what I thought with NT, which is that drivers are much more isolated. If I understand it correctly drivers can still cause a kernel panic, but Microsoft requires that signed drivers pass a formal verification, which has greatly cut down on blue screens. I'm just an armchair observer though, so I'm not an expert. I was always greatly impressed by Windows' recent ability to recover from something like a display driver crash with hardly a hiccup. That's pretty impressive voodoo.