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Missing Kernel Patches
BlueEar writes: "There is an interesting, short story posted on the Gentoo Linux site. It talks about kernel patches created by Linux distributors that while publically available never get submitted. It even gives an example of one 'no brainer' patch that has been sitting over a year, without being incorporated into the 2.4.x distribution. The article ends with an appeal to Linux community to keep those patches flowing to Marcelo."
What most people don't realize that someone who puts together these releases like Linus or Marcelo is by no means omniscient. The kernel is a huge piece of work, and no one person can know what's happening in every corner of the thing. Most of Marcelo's time goes to merging patches, so he surely cannot go around the net looking for what ever fixes some distributor might have used or even checking out how come some fix that was circulating around before was never submitted to him.
What's nice is that nowadays there seem to be a couple of "patch harvesters" on the lkml who create their own releases (Alan Cox is now one of these people!) and persistently keep submitting forgotten patches.
Many of the distributor's fixes are ad hoc kludges that are designed to quickly making the thing *work*, ignoring elegance and maintainability... even when they do fix things, in the long run we don't want to take all of them into the kernel.
Based on that sample patch they gave it seems that an unpatched system allocates one more page of memory than it actually uses. Sure it's not nice in terms of resource use but it's hardly going to affect the operation of the kernel.
Obviously with the number of people (especially "power" users) who run the "generic" kernel any critical flaws are going to get uncovered and patched. I think these kind of issues, that directly affect the stability of the kernel are more important than "clean up" type patches this article describes.
Obviously they're nice to have, but it's hardly a priority when there are bigger fish to fry.
Yeah, that's what Marcelo needs, every clueless dweeb bombing them with endless copies of "this rmap vm is so 1337 why dont j00 include it in 2.4.19!"
An example of why a particular patch might not be accepted, even though it seems like a "no-brainer", is because it would be for too specific a purpose. It might optimize the kernel for one particular application, at the expense of others. One of the best things about Linux is that it is general-purpose: suitable for everything from palmtops and embedded systems to servers and enterprise applications.
A patch to aggressively cache the disk in memory, for instance, might be good for servers but not for embedded systems. So, I could understand how a patch would be rejected in this case.
As an example, a company I once worked for made many minor changes to the Linux kernel. Since Linux is GPL, I made a webpage publishing these changes, and unlike the company, my webpage is still in existence!
Splash Open Source Page
These changes would be too narrow in focus to apply to the Linux kernel for everybody, so we never submitted them.
Dr. Demento On The 'Net!
The same thing sometimes happens to the BSDs, where a bug will be fixed (usually in Open) and nobody gets around to integrating the same fix into the others.
It seems to me that much of this could be automated... for each patch which gets added into the xBSD source tree, compare the contexts to the yBSD and zBSD source trees and alert a human if it looks like there's a match.
But for this to be effective, I think that patches would have to have labels attached, since it's really only bug fixes for which this is necessary.
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Out of all the people involved with this on the planet, not one person could be assigned the task of doing this sort of sweeping up? Lots of busy folk out there, certainly, but those people were found to do the major stuff in the first place... And please, save the "well why don't you do it, smarty man?" responses for someone that sort of backwards logic will work on, thanks, I'm just making an observation, not an accusation.
BytesTemplar.com
"Out of all the people who moan that these sort of issues should be fixed by someone else isn't there someone who could be ordered to do this in their own free time instead of having fun to fix this for small minded whingers like me?"
Yes, fortunately the kerneljanitors project does this. And I think they do it out for altruistic reasons rather than because someone assigned them to.
This is not backwards logic. I am not suggesting you do it. I am suggesting you stop whining about there being noone else to do it when you can't be bothered either.
Carpe Daemon
Careful.
:wq
Besides, you operate under the assumption that I haven't contributed anything to the kernel, which would be wrong.
I think the assumption he operates on is that you can't be bothered to go through and submit patches, as you were complaining that someone should to do it.
It's not an issue that people aren't working on the kernel enough, it's that there are too many mad scientists, and not enough henchmen.
could be that whoever produced the patch (Mandrake in this case) got tired of having to submit it over and over, only to have it ignored bye (for example) Linus. i'm not complaining here, but i think at least part of the solution to this "problem" relates to how the patches are handled by the maintainers.
Acts@core.mailboks.com Acrux@core.mailboks.com Adam@core.mailboks.com Adar@core.mailboks.com Ada@core.mailboks.com
No, this is not a troll. Hear me out. This is an example how this work can be done using a good tool. I use Visual Sourcesafe here as an example, but any tool with the same functionality described below will do:
Visual Sourcesafe has the ability to merge back changes automatically in branch B from branch A when they have the same parent.
Say, you have the kernel v2.4.10. You branch off another project from it, call it v2.5.0. When you fix a bug in 2.4.11, you can merge it back into 2.5.0 without a hassle, it can be automated or you can do a visible merge when there are conflicts. The other way around also does work. So you can do this even further: branch of a prerelease 2.4.11-pre branch and a 2.4.11 branche from the 2.4.10 branch. Create fixes in 2.4.11-pre, merge them back into 2.4.11 after testing and when you're done, release 2.4.11 and get rid of 2.4.11-pre.
This is inside a versioncontrol system, you don't have to hassle around with a lot of files you have to merge by hand which will increase the risk for errors.
Of course, Visual Sourcesafe is just 'a' tool, you could use another which has the same functionality and is perhaps Open Source (I don't know of any but I'm sure others will). Doing this job by hand TODAY is erm... not understanding why we have computers in the first place. That's right: to serve mankind.
Never underestimate the relief of true separation of Religion and State.
Marcelo is certainly well aware of the existance of many patches that never get included in the main kernel tree, as he maintains Conectiva's kernel package which contains a large amount of vendor patches. He certainly has his reasons for not including the patches to the official kernel -- it certainly would make his life much easier if he reduced the number of vendor patches in Conectiva's tree applying some of these to the main tree. Marcelo is being very conservative regarding the 2.4 tree, and I believe that's the way it should be, considering it's a "stable" kernel.
I am wondering if the distributors themselves don't have too much interest in offering patches upstream
This plain isn't true, and whoever wrote the article on gentoo.org just shows he doesn't have the slightest hint of a clue.
There are some good reasons not to blindly apply distributor patches into the main kernel (for example, we have quite a few workarounds for bugs, but the right way to fix them in the official kernel is to fix them, not to add workarounds), and there are some other things preventing other patches from getting in (e.g. Linus not having the time to handle them immediately).
Other stuff is controversial (such as Red Hat Rawhide kernels putting in the Rik VM rather than the AA VM currently in upstream).
The patches are sent upstream, but at least Red Hat doesn't believe in forcing upstream maintainers to accept all patches we send.
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... because once their patches are included they wouldn't have to maintain them themselves. So i don't see, how it could be a waste of time to send obvious patches in, or alert the kernel-maintainer of problems with recent patches that came up in their testing.
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Then why are you posting on /.?
I was running at 80x34 first. I had to maximize the terminal to 129x44 to be able to read it. I doubt your terminal is even close to 1024x768 characters...
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The Cap is nigh. Time to get a fresh new account.
As a maintainer of a package which is distributed via many linux and *BSD distributions, I'd like to complain on the behalf of software authors everywhere. The linux distributions are nutoriously bad about applying patches to their rpms (say) but never submitting them back to the authors of the package themselves. The BSD distributions are just as bad. The infamous FreeBSD port tree also frequently houses patches that never make their way back to developers.
I'm not sure how this could ever be considered a good thing, as the project authors must spend time searching through distribution source releases looking for patches, which takes time. The distributions must continually apply their patch to a changing source tree (and I'm sure it'll eventually break and need reworking), so they loose time as well. This is one case where communication really could be a very positive thing.
sigh... It's about time I went to search for patches again...
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From Kerneltrap's wonderful interview with Andrew Morton:
The above article should be required reading for those following/concerned about kernel development.
It is extremely difficult to be proprietary when you are bound by the GPL. If your referring to Red Hat's using Rick's VM, there would be no stopping you from nabbing a
I also use Debian and must tell you that they make changes to the kernel. That is good, however. It just isn't practicle for a distro to try and update to the latest kernel. Plus if you like me, the first thing you do on any distro is nab a tarball from ftp.kernel.org.
...And no, I'm not trolling.
/.).
People talk about the exchange of ideas between the BSDs and Linux, and I think that a core group like FreeBSD's would be a great idea for the Linux world.
It seems like we are running into more and more scaling issues with the people behind Linux than with Linux itself. This is no fault of theirs. Linux is too big a project for a "the buck stops here" kind of person like Linus.
Obviously, Linux is Linus's brainchild, and he can do whatever he likes with it (yes, I know the GPL allows forking, but think of how a kernel fork would be recieved on
I don't believe that Linux can attain the kind of consistency (and that is not the goal anyway) of FreeBSD or NetBSD, I think they might be able to fix some of the kernel patching and architecting problems if an elected core team could work on this.
-Peter
. Penguins Surely Ca