Devs Discuss Android's Possible Readmission To Linux Kernel

MonsterTrimble writes "At the Linux Collaboration Summit, Google and Linux Kernel Developers are meeting to discuss the issues surrounding the Android fork and how it can be re-admitted to the mainline kernel. From the article: 'James Bottomley, Linux SCSI subsystem maintainer and Novell distinguished engineer, said during the kernel panel that forks are prevalent in embedded systems where companies use the fork once, then "throw it away. Google is not the first to have done something like this by far, just the one that's made the most publicity. Hopefully the function of this collaboration summit is that there is some collaboration over the next two days and we might actually solve it."'"

Comments

Yawn

[Anonymous Coward]

What does this have to do with the iPad? I come to slashdot for iPad stories, not stuff real nerds have never heard of.

Re:Yawn

[ickleberry]

Really? I come to slashdot to read about how Google is taking yet another piece of technology we have taken for granted for many years and turning it into an online, ad-based Clout 2.0 service and tunneling it through HTTP with JSON and SOAP to their servers for a nice intense data-mining session for better targeted ads and predicting future crimes one might commit.

Re:Yawn

[girlintraining]

Really? I come to slashdot to read about how Google is taking yet another piece of technology we have taken for granted for many years and turning it into an online, ad-based Clout 2.0 service and tunneling it through HTTP with JSON and SOAP to their servers for a nice intense data-mining session for better targeted ads and predicting future crimes one might commit.

Unbridled capitalism and the apathetic and ignorant citizens are to blame for that. Your personal data can be aggregated and monetized, and for the foreseeable future, there's very little legislation to prevent this and very little awareness of how pervasive such technology is. My whole generation is living with software riddled with government and corporations that have put back doors into everything, freely share data with each other, and those living in urban areas (the majority of the population) are rarely out of contact with some device or another wired into the global network, tracking their movements, purchases, communications, relationships, and every aspect of your life. Remotely-enabled webcams, cell phones that can be turned on silently to broadcast everything it hears and sees, and laptops and routers that can be readily converted into eavesdropping devices, just to name a few of the many things that are out there right now. And the only reason it's not all interconnected more seamlessly is because the technology is still rapidly evolving and hasn't reached a stable plateau where convergence is possible, although the internet has made a giant leap forward in enabling that future. The NSA spends billions each year trying to keep up with infrastructure changes and only is able to harness a fraction of that potential.

But I mean, comeon -- what do you expect from a world where we find it okay to setup metal fences with razor-tipped wire and cameras everywhere as "official protest zones", where we have passports, credit cards, (and soon ID cards) that can be remotely scanned to identify you... put it all together. Where do you think this all ends?

Re:Yawn

[russotto]

It is entertaining that a tinfoil hat will work quite well at protecting your wallet from remote scans.

Only if you keep your wallet on your head.

Backwards?

[Sponge Bath]

Google must now balance any desire to respect the wishes of the Linux community for compatibility with the more diverse, competing - and not always logical - interests of those now adopting Android and its own plans.

I did a double take on this statement.

What I've seen on the kernel mailing list is more a conflict of commercial developer's desire for compatibility (across kernel versions) with the core kernel developer's more diverse (and not always logical) desire to push pet projects and make frequent cosmetic changes that creates a hellish torrent of code churn. The lack of well defined kernel driver interfaces means a lot of time spent chasing the latest changes instead of adding features or fixing bugs.

Re:Backwards?

[Microlith]

The only people I've seen clamoring for a static, unchanging driver interface are those writing proprietary drivers. Last I checked, changes to the interfaces by someone puts the onus on them to fix all the calls to it in the kernel, which is why getting your driver into the tree is considered better than keeping it closed.

That said, if you're keeping your driver closed it's a problem you're bringing upon yourself.

Re:Backwards?

[Daniel Phillips]

The truth is, Google doesn't really get open source even though its livelihood depends on it.

Re:Backwards?

[Sponge Bath]

That said, if you're keeping your driver closed it's a problem you're bringing upon yourself.

I should have been more clear. I'm talking about drivers in the main kernel source. I know the linux kernel mantra: binary only drivers are evil (I agree), out of tree open source drivers are slightly less evil. I think out of tree open source drivers can be useful when inclusion to the main kernel is denied because some critical functionality is deemed unnecessary by the gatekeepers who require it to be removed before consideration. But I'm not even talking about that.

Last I checked, changes to the interfaces by someone puts the onus on them to fix all the calls to it in the kernel...

That's the theory. Here is how it works in practice: A pet project or cosmetic change that touches a lot of code is implemented and then dependencies are grepped. The dependencies are fixed up in a cut and paste way. Sometimes more important drivers get some review to make sure nothing breaks. Everything else just gets shipped if it compiles. Then when that kernel is used in a distribution, sometimes years later, many drivers are suddenly broken and you have to back track to see which change took it out. If someone has a lot of time and desire to support a "lesser" driver then they can spend all of their time playing catch up, but that wears out volunteers quickly and annoys commercial vendors.

Re:Backwards?

[Sponge Bath]

The last thing Linux needs is a set-in-stone kernel interface...

I can agree with this, but then again I don't see anyone asking for that.

How about something in between, say a well defined interface that is stable for a reasonable period of time with clear points of deprecation and then replacement with improved interfaces? Windows's driver interface is not set in stone with never ending backwards compatibility, you can't use Win 9X drivers on XP. Yet a binary driver that works on Windows 2K has a reasonable chance of running on Vista.

There needs to be a balance between improvements/changes and stability/maintainability.

Re:Backwards?

[dgatwood]

Wrong, absolutely wrong. Greg K-H himself has explicitly said that he WANTS people with drivers for even highly obscure devices to merge them into the mainline kernel. It doesn't matter if your capacitive multi-touch screen is only used in one phone; the code is useful to have publicly available in the kernel as a reference. Furthermore, as more drivers for similar devices are merged into the kernel, commonalities between them can be found, and more generic drivers can be created.

Based on what I've seen over the years (as a developer on a project that never made it back into the mainstream kernel), the problems with this approach are threefold:

1. Nobody maintains most of them. Most of the 5% of drivers that everybody uses are already in the kernel tree. Of the remaining 95%, half of the drivers don't build at all, and most of the other half don't work. If they're barely maintained now, you can bet money that they won't be maintained at all when some kernel tree maintainer gets a hair up his/her backside and decides that a particular fix isn't elegant enough and won't take the changes....
2. The tree is already too large. If every driver out there were in the tree, checking out an update to the tree would be horribly painful, the source packages that distributions include would become huge, etc. The bigger it gets, the fewer people are going to be willing to maintain their drivers inside that tree, so in the long run, encouraging people to put their drivers in the tree is just going to cause other drivers to move back out of the tree, eliminating any real benefit.
3. Many such drivers are outside the tree because they require substantial changes to some subsystem in order to build them. Now one could argue that these changes should be made to those subsystems to make them more general, or one could argue that those drivers are so specialized that nothing else will use them, so there's no reason to bother. That's often not an easy question to answer, and tends to result in highly political shouting matches, with the end result being that the driver never goes in, which is usually why those drivers got published outside the kernel tree to begin with.

There are ways to solve these problems, of course; IMHO, they basically amount to:

• Design a kernel build infrastructure that can easily bring in driver sources from third-party sites (like a ports collection, but for kernel drivers). With proper categorization, this can provide all the same benefits as having the drivers in the main tree, but also allows for a richer tagging scheme instead of a simple filesystem hierarchy, which should actually make it significantly easier to spot patterns (for example, seeing that there are now eighty-seven different drivers for capacitive touchscreens, or whatever), all without bloating the tree that everybody has to download.

• Subject all kernel API changes to a formal API review process in which no API change can go in unless the owners of all drivers in that area agree that the design is acceptable and will meet with their needs. Set up a reasonable set of rules of engagement (e.g. A. don't shoot down the idea just because you don't need it, B. don't shoot down an idea without proposing an alternative). And so on.

• Redesign the kernel interfaces in an object-oriented language. Such designs make it more likely that drivers can extend the interfaces without requiring major changes to the core code. The Linux kernel sort of halfway adopts this approach insofar as code reuse is concerned, but does so in ways that aren't particularly clean and neat.

  For example, if I were writing an ATA driver and needed to do almost everything the same way but change the behavior of one function in some other library... say down at the block device layer, I'd either have to make a change to the block device layer with some special case detection code or I'd have to copy entire swaths of code at the ATA device layer and c

Tricky

[Monkeedude1212]

"{
        '{
                "{
                  }"
                "{
                    }"
          }'
}"

I wasn't sure if 5 quotes at the end of the article was correct or not. I decided to employ brackets to handle the scenario. Taking out the wording, my findings are above. It IS correct.

Is it bad that this was the most exciting part of the article to me?

Cheaper costs

[girlintraining]

It's a real problem -- Android is easily the most hackable phone out there. And that's exactly the kind of thing cell phone manufacturers in this country don't want. It's bundled services that they make their fortunes on -- selling overpriced phones, contract cancellation fees, locking in devices, and more. Android threatens to separate the market into service providers and device providers and up until now, the service provider dictated what the device providers could do.

Imagine if you could just eject your SIM card from your phone, plug it into your computer, and browse the net, take phone calls, etc., then eject it like it's a memory card, slap it back into your phone, and go off to school, work, wherever. Or using bluetooth so that as soon as you get home, it automagically resyncs all your e-mails, text messages, and more. There's so much the technology can do -- and the only reason it's not happening is because service providers want to charge for everything, rather than simply flat-rating everything on a per minute, day, or megabyte use.

My Sidekick recently lost the ability to send files to my computer over bluetooth. Why? Because of an OTA update that disabled that. So now I can't just sit my phone near my laptop and transfer my pictures out of it, I have to open the back up, eject the little card, plug it into my system, copy the files, and then do the reverse. Very cumbersome when before it was 'click icon, drag files'.

It's complete and utter bullshit that cell phones are as powerful now as desktops were ten years ago sitting in the palm of my hand, and yet they have less than a third of the capability. And not a one of them is really interoperable with any other except on the most primitive level. Hell, the dialup days of computing offered more functionality and standardization than the cell phone market does. Why should a 14.4k modem and an antiquidated pentium 133 have more communication functionality than today's devices? Hell... it even cost less.

Re:Cheaper costs

[EvanED]

It's a real problem -- Android is easily the most hackable phone out there.

I'm not so sure... I think the Nokia N900 has got it beat.

Re:Cheaper costs

[girlintraining]

I'm not so sure... I think the Nokia N900 has got it beat.

Yeah, but who's heard of the Nokia N900, or even knows what that means, outside geek circles? On the other hand, billboards and TVs everywhere are blasting out "Droid does". For bringing a hackable system to the masses, Android has it beat.

Re:Cheaper costs

[cynyr]

i second that.

you have hardware level access to the N[789]00 devices. I would like an ipad sized n900. that would be a great device.

Re:Cheaper costs

[drsmithy]

Yeah, but who's heard of the Nokia N900, or even knows what that means, outside geek circles? On the other hand, billboards and TVs everywhere are blasting out "Droid does". For bringing a hackable system to the masses, Android has it beat.

But "the masses" aren't interested in hacking it, thus making said hackability essentially irrelevant to anyone who isn't in "geek circles" anyway.

Re:Cheaper costs

[girlintraining]

But "the masses" aren't interested in hacking it, thus making said hackability essentially irrelevant to anyone who isn't in "geek circles" anyway.

They said the same thing about the internet, twenty years ago. And yet look what the hackers of the world built out of the refuse of wires and chips that the corporations of then said was useless and had no commercial value. Now they're fighting to tax it, control it, and some countries have declared it an inalienable human right to have it.

Maybe it has no value to them, but that's because they don't know the value of it yet. It's our job to find it and tell them. You just haven't been around long enough to realize the purpose of your own learning yet. Your individuality, your knowledge and talents, are not for your own gratification. The purpose of the democratic process, which the internet comes closest in form and function, is not to create a great country, or great works, but to create great people.

Hacking is therefore the highest form of the democratic process; Not because of what we do, but for what we share.

Would you rather have completely unsupported HW?

[tepples]

If hardware makers can't include third-party code or processes that they aren't permitted to sublicense as free software, then perhaps they won't write a driver at all. Instead of proprietary drivers, you'll have completely unsupported hardware.

Re:Would you rather have completely unsupported HW

[cynyr]

yes, if it's enough of a market for them, they will make sure that they get support from upstream, if enough companies ask for linux support for subassembly Y then maybe it will change. If you really feel you need to keep it closed, do like nvidia, or handle it yourself.

Re:Would you rather have completely unsupported HW

[Microlith]

What's your point, that we should encourage closed drivers by setting the APIs in stone for years on end? Allow the non-open to dictate the actions of the open?

That's not -my- problem. It's theirs. They choose to stay closed, so when the APIs change no one else can fix it but them. They have no room to bitch about unstable APIs in an open kernel that is constantly changing, when they won't commit to being open themselves. Others do, and as a result don't have nearly the problems. It's a cost they must accept, or they can do as you suggest and stop.

Where's the ROI?

[tepples]

if it's enough of a market for them

It isn't. Because GNU/Linux has roughly 1% of the desktop share, a lot of companies don't see the return on investment in getting support from upstream.