Linus Denounces NDISWrapper, Denies It GPL Status

eldavojohn writes "On message boards, Linus Torvalds was explaining why NDISWrapper is not eligible to be released under the GPL even though the project claims to be. Linus remarked, "Ndiswrapper itself is *not* compatible with the GPL. Trying to claim that ndiswrapper somehow itself is GPL'd even though it then loads modules that aren't is stupid and pointless. Clearly it just re-exports those GPLONLY functions to code that is *not* GPL'd." This all sprung up with someone restricted NDISWrapper's access to GPL-only symbols thereby breaking the utility. Linus merely replied that "If it loads non-GPL modules, it shouldn't be able to use GPLONLY symbols." As you may know, NDISWrapper implements Windows kernel API and then loads Windows binaries for a number of devices and runs them natively to avoid the cost and complication of emulation."

Comments

Linus has already changed his mind

[baadger]

Quite frankly, my position on this has always been that the GPLv2 explicitly covers _derived_ works only, and that very obviously a Windows
driver isn't a derived work of the kernel. So as far as I'm concerned, ndiswrapper may be distasteful froma technical and support angle, but not against the license.

-- Linus, in this post

Re:Linus has already changed his mind

[Chris Mattern]

No, Linus's position here is perfectly consistent. ndiswrapper itself can be covered by the GPL, but when you use ndiswrapper, your kernel is no longer GPLONLY, even though ndiswrapper is itself GPL, because ndiswrapper then loads and runs the Windows driver which is *not* GPL. The fact that ndiswrapper loads and runs non-GPL code doesn't make it non-GPL, but it certainly makes the kernel in which it is running not GPLONLY. If ndiswrapper loaded a GPL driver, the kernel would still be GPLONLY (which, in fact, it wouldn't be if ndiswrapper was not GPL). It's just that ndiswrapper's basic purpose means it'll never load a GPL driver.

Re:Linus has already changed his mind

[SirTalon42]

Linus isn't saying you can't use ndiswarapper. What'll happen, though, is when you report a bug they'll see your kernel has been tainted by a random binary blob they can't touch, and your bug report will be much less useful to them and it'll probably be marked as being much lower priority unless it can be confirmed that the binary blob isn't causing the problems (i.e. re-create the problem without the blob, either by not loading the module or from another machine without the module to begin with).

Again, no ones complaining that you're using it to load non-GPL code.

Summary completely mistaken

[tarm]

Summary is missing a HUGE portion of what actually happened. The discussion continued. After the discussion, Linus applied a patch to ALLOW access to GPL_ONLY symbols (for those who care, it's git commit 9b37ccfc637be27d9a652fcedc35e6e782c3aa78).

It's fixed in 2.6.24-rc4

[Englabenny]

Look at the second entry from the top in the changelog:

http://kernel.org/pub/linux/kernel/v2.6/testing/ChangeLog-2.6.25-rc4

The battle is over, the discussion is at end and Linus has already signed off a change to restore Ndiswrapper functionality.

for those who lack understanding...

[Edgewize]

The stance isn't as crazy as the context-free summary makes it out to be. Linus isn't talking about the license for the ndiswrapper code. He's talking about access to kernel functions which have been marked as "GPLONLY". These are functions which are intentionally not exported to non-GPL code. Linus is saying that allowing ndiswrapper to use them is equivalent to allowing calls from non-GPL windows binary drivers. Which is true.

The debate then is whether or not this should be considered a problem. The contributors who added many of the GPLONLY functions may have different opinions on the topic. Linus hints that the contributors for the USB functions would prefer a strict interpretation and deny ndiswrapper access to the GPLONLY kernel-level functions, because there is a perfectly good user-space API. But everyone involved agrees that ndiswrapper is will never live in user-space, because there's no programmer who would do it and it's a crazy idea anyway. Anyway you slice it, it's clear that ndiswrapper will get fixed one way or another, and nobody is accusing the ndiswrapper project of misusing the GPL.

In summmary, it's a tempest in a teapot: someone accidentally broke ndiswrapper, kernel API discussion ensues, Slashdot posts inflammatory summary, life goes on.

Re:You can't win this one, Linus

[richlv]

it's quite important to understand the issue, i think.
it has been repeated in the thread several times already, but i'll try again (from my, outsider viewpoint, but i'd hope somewhat educated one :) ) - nobody is _breaking_ anything.

short interpretation by me :
kernel has a variable which denotes that it is gpl only - that is, the core and all loaded modules are gpled.
this shows to people trying to debug things that they can debug everything and there are no binary modules that break shit in unexplainable ways.
now, if a binary module is loaded, kernel notes in the variable that it is no more gpl only and breakages can be extremely hard to debug and impossible to fix. i guess you'll agree we don't want the kernel devs to waste time on such cases.

now, ndiswrapper itself poses as gpl, thus it does not taint the kernel, but it then loads modules inside itself...

so you get a tainted kernel that does not identify as one.

and that is the only behaviour which is going to change.

if i have misunderstood things miserably, correct me, thanks :)