Re: [GIT PATCH] more Driver core patches for 2.6.19



On Wed, 13 Dec 2006, Greg KH wrote:

It's a stupid test module for the uio core for isa devices. It's not
the main code, or core.

Doesn't matter.

IT IS SO FUNDAMENTALLY AND HORRIBLY WRONG THAT I REFUSE TO HAVE IT IN MY
TREE.

As an "example", the _only_ thing it can possibly ever do is to just
confuse people - in other words, it's an _anti_example, not a real one.

Ok, I can pull this example module out if you want, but people seem to
want examples these days. If I do that, any objection to the rest?

I'm really not convinced about the user-mode thing unless somebody can
show me a good reason for it. Not just some "wouldn't it be nice" kind of
thing. A real, honest-to-goodness reason that we actually _want_ to see
used.

No features just for features sake.

So please push the tree without this userspace IO driver at all. And if
you actually have a real user, not just an example, that is worthy and
shows why such a driver in user space is actually a good thing, _then_ we
can push that.

In other words, I'd like to see code that uses this that is actually
_better_ than an in-kernel driver in some way.

For USB, the user-mode thing made sense. You have tons of random devices,
and the abstraction level is higher to begin with. Quite frankly, I simply
don't even see the same being true for something like this.

Btw: there's one driver we _know_ we want to support in user space, and
that's the X kind of direct-rendering thing. So if you can show that this
driver infrastructure actually makes sense as a replacement for the DRI
layer, then _that_ would be a hell of a convincing argument.

There may be others. Feel free to fill in the blank: ________.

Linus
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

Relevant Pages

  • Re: [PATCH] uio: User IRQ Mode
    ... In this mode the user space driver ... is responsible for acknowledging and re-enabling the interrupt. ... This can easily be done without your patch. ...
    (Linux-Kernel)
  • Re: [PATCH] uio: User IRQ Mode
    ... This patch adds a "User IRQ Mode" to UIO. ... In this mode the user space driver ... is responsible for acknowledging and re-enabling the interrupt. ...
    (Linux-Kernel)
  • Re: [PATCH] uio: User IRQ Mode
    ... This patch adds a "User IRQ Mode" to UIO. ... In this mode the user space driver ... is responsible for acknowledging and re-enabling the interrupt. ...
    (Linux-Kernel)
  • Re: PCI lib for 2.4 //kwds: pci, dma, mapping memory, kernel vs. user-space.
    ... They are *all* you can use for a user-space driver. ... internal kernel interfaces that are not accessible from user space. ... You should be able to do high speed data streaming from user space -- ... I'm measuring 10 microseconds from a PCI board asserting an interrupt ...
    (Linux-Kernel)
  • Re: Writing to a device at a known physical address
    ... Your program would fail at least on this architecture. ... and hardware registers instead. ... is how do I access /dev/mem from user space? ... Every example driver I've ...
    (comp.os.linux.embedded)