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Torvalds On Pluggable Security Models

kdawson posted more than 6 years ago | from the plain-speaking dept.

Security 216

eldavojohn writes "The KernelTrap highlights an interesting discussion on pluggable security models including some commentary by Linus Torvalds. While Torvalds argued against pluggable schedulers, he's all for pluggable security. Other members were voicing concerns with the pluggable nature of the Linux Security Model, but Torvalds put his foot down and said it stays. When asked why his stance was different between schedulers and security, he replied, 'Schedulers can be objectively tested. There's this thing called 'performance,' that can generally be quantified on a load basis. Yes, you can have crazy ideas in both schedulers and security. Yes, you can simplify both for a particular load. Yes, you can make mistakes in both. But the *discussion* on security seems to never get down to real numbers. So the difference between them is simple: one is hard science. The other one is people wanking around with their opinions.'"

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216 comments

Well (3, Funny)

homey of my owney (975234) | more than 6 years ago | (#20817591)

He's right.

Re:Well (1, Interesting)

QuantumG (50515) | more than 6 years ago | (#20817621)

Linus is never right.

He's convincing.

Re:Well (0)

Anonymous Coward | more than 6 years ago | (#20817699)

the 2 are the same dumbass.

Re:Well (0)

Anonymous Coward | more than 6 years ago | (#20817715)

Hah, you were trolled by a Linus loving moderator - or were you?

Re:Well (0)

Anonymous Coward | more than 6 years ago | (#20817839)

Whereas you manage to be both wrong *and* unconvincing.

Re:Well (0, Flamebait)

gweihir (88907) | more than 6 years ago | (#20817871)

No. Linux is not convincing. He is arrogant and more and more clueless. Unfortunately people seem to be so in awe of him, that allmost nobody is willing to tell him that he has he is "wanking around" about a lot of things he obviously does not really understand.

Re:Well (-1, Troll)

QuantumG (50515) | more than 6 years ago | (#20817915)

He's clearly convincing to *some* people. Typically people who have no idea what he is talking about.

Re:Well (1, Funny)

Anonymous Coward | more than 6 years ago | (#20817923)

Who's this linux fellow you're talking about?

I feel sorry for him to have such geeky parents, though.

Re:Well (4, Funny)

HeavensTrash (175514) | more than 6 years ago | (#20817929)

Linux is arrogant and clueless? I didn't know an OS could have human traits.

Re:Well (5, Insightful)

rumblin'rabbit (711865) | more than 6 years ago | (#20818293)

I've used lots of software that was arrogant and clueless. Hell, I've written software that was arrogant and clueless.

Re:Well (1, Insightful)

Anonymous Coward | more than 6 years ago | (#20817931)

as opposed to wanking around on slashdot complaining about Linus. I know what he has done for us lately, what have you done?

Re:Well (1)

Raineer (1002750) | more than 6 years ago | (#20818123)

No. Linux is not convincing. He is arrogant and more and more clueless. Unfortunately people seem to be so in awe of him, that allmost nobody is willing to tell him that he has he is "wanking around" about a lot of things he obviously does not really understand.
What has been your contribution to the issue?

Re:Well (0)

Anonymous Coward | more than 6 years ago | (#20818167)

"His name's not Die Hard!"

Re:Well (2, Interesting)

Anonymous Coward | more than 6 years ago | (#20818377)

No. Linux is not convincing. He is arrogant and more and more clueless. Unfortunately people seem to be so in awe of him, that allmost nobody is willing to tell him that he has he is "wanking around" about a lot of things he obviously does not really understand.
How would you sound if you had been herding cats for years? Linus refuses in this case to chose whether the user cats get their tuna from Starkist or Chicken of the Sea. This makes the cat from Starkist and the cat from Chicken of the Sea mad at him. The user cat gets handed a can opener and while they can chose either source they want some of them complain that they have to chose and open the can. In many cases the distro-cat makes the choice and forks out the tuna from their choice of cans to their user cats. Again, some appreciate the choice and others hiss and threaten to scratch with the target of their threats anywhere from the distro-cat to the security-cats or to Linus.

Every time Linus has a decision to make there are two or more tom-cats out screeching and raising hell on the fence outside his window. Sometimes the tom-cats are looking at him like he is a tabby and your suprised if every so often he throws a boot at the tom-cats?

Re:Well (1)

Amani576 (971730) | more than 6 years ago | (#20818825)

I like the cat analogy. And you make a very valid point, and one that makes me wonder why people are so pissed of at Linus. It's not like he's really telling anyone what they can or can't do. And hell, even if he is, whoop dee doo... it's Linux, if you don't like what he says to do, change it, put your own scheduler in and shut the hell up. The same goes for security. It's your own choice, much like using Linux and how you want it, over using Windows or Apple and having everything "picked" for you. Get over the ME ideas people... it's not about what YOU want... it's what EVERYONE wants. Linux is a democracy, with nice anarchistic undertones...
But whatever, I'll probably get modded a troll for this.
GR

Re:Well (5, Insightful)

deek (22697) | more than 6 years ago | (#20818745)

No. Linux is not convincing. He is arrogant and more and more clueless. Unfortunately people seem to be so in awe of him, that allmost nobody is willing to tell him that he has he is "wanking around" about a lot of things he obviously does not really understand.


You're not being very convincing either. You call Linus all sorts of things, without actually saying specifically why you think he is arrogant, clueless, and has no understanding. I'm open to the idea that he may be, but your post certainly does nothing to convince me of it.

At least Linus has specifically stated why he thinks security guys are "wanking around". It's because security people state that "only my version is correct", when they don't quantify exactly why this is the case. That certainly meets my criteria for "wanking around". Linus appears to have made a good judgement call.

Re:Well (4, Interesting)

Trillan (597339) | more than 6 years ago | (#20817627)

He is right, definitely But being theoretically able to measure something doesn't mean it's practical or the the results are always useful.

Re:Well (0)

Anonymous Coward | more than 6 years ago | (#20817817)

Or that the results are any more conclusive than "it's a tradeoff" or "it depends on your load characteristics".

Re:Well (1)

Vellmont (569020) | more than 6 years ago | (#20818141)


But being theoretically able to measure something doesn't mean it's practical or the the results are always useful.

The thing is that Linus isn't talking about the general case here, he's referring specifically to these two cases. If you've got some kind of performance consideration for scheduling that's not being measured, or have good evidence that the current measurements aren't relevant to the user experience, you should bring it up. If you're just speaking in a general philosophic way, that's nice and all but I don't see how it's relevant.

Linus Torvalds is gay. He married RMS! (0)

Anonymous Coward | more than 6 years ago | (#20817669)

Secretly, Linus Torvalds and Richard M. Stallman have become married under the control of manwitch Eric S. Raymond. Quick, run away from the GNU!

Linux is dying! Eric S. Raymond confirms it!

WTF w/ Teh Lunis? (0)

Anonymous Coward | more than 6 years ago | (#20817937)

Teh Lunis sez:

The other one is people wanking around with their opinions.

Doesn't Teh Lunis understand what Teh FOSS is all about? It's ALL about wanking around with your opinion. Oh, and it's all about choice (meaning, any choice except Teh MiKKKro$$$oft).

Who could have imagined Teh Lunis just doesn't get it? Teh Stallman gets it, so why doesn't Teh Lunis?

HUURRRR (-1, Troll)

Anonymous Coward | more than 6 years ago | (#20817603)

LINUS SAID WANK

wanking around (5, Funny)

Anonymous Coward | more than 6 years ago | (#20817625)

I've been wanking around with pluggable opinions for years, and I turned out okay.

Re:wanking around (0)

Anonymous Coward | more than 6 years ago | (#20817745)

Careful, you'll go blind.

Don't let it become like Windows. (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#20817647)

One of the reasons that Windows is so insecure is because of the complete lack of stability with respect to its security model.

We'll ignore the fact that for DOS, Windows 3.11 and even up to Windows ME, there is essentially no security policy. We'll just focus on the Windows NT-based systems. Even there, there have been massive changes between each major release. The Windows 2003 security model differs in many ways from that of Windows 2000. Windows XP and Vista bring their own complications on the desktop side of things.

It gets to the point where with any heterogenous network, it becomes very difficult to ensure that all of the systems are secure, just because it becomes difficult to coordinate between all of the different security models. And that's just when using different versions of Windows. When you start getting UNIX systems involved in the network, it becomes an even bigger hassle.

Spot on Torvalds... (3, Insightful)

cez (539085) | more than 6 years ago | (#20817675)

I think Torvalds is right on this one. Until we can quantify security as we can scheduling performance, which he argues for, why shouldn't he keep LSM modular?


If not, an artificial limit onto the integrity of the system would be created. Sure SELinux is a viable option, but why should we think it is the best ?

Re:Spot on Torvalds... (4, Insightful)

gweihir (88907) | more than 6 years ago | (#20817835)

Security cannot be quantified in hard numbers, since security is allways relative to the resources the adversary has. True, you could plan for some specific adversary. But that would be pretty meaningless. Also resources of an adversary is not a simple number that can be compared. Some thinks are limited to pecific attackers. Other stuff depends on money and/or time. Yet other stuff requires a specific type of competence. That is also why there typically is no "best" solution.

So, no, security folks are not "wanking around" as some specific asshole seems to claim, they are using the best tools available to evaluate adequacy of different security solutions. Those that do not get this are not getting what security is about and what the state of the art is. These people should better stay far away from security-relevant decisions and let people that at least understand present technology in that area make the decisions.

Re:Spot on Torvalds... (2, Insightful)

cez (539085) | more than 6 years ago | (#20818059)

So, no, security folks are not "wanking around" as some specific asshole seems to claim, they are using the best tools available to evaluate adequacy of different security solutions. Those that do not get this are not getting what security is about and what the state of the art is. These people should better stay far away from security-relevant decisions and let people that at least understand present technology in that area make the decisions.
"Wanking around" was a poor word choice at best, and I agree that people "that at least understand present technology in that area make the decisions". However, that doesn't invalidate his argument of modulization.


The best of present technology is modular to a certain extent, from a micro and macro perspective of system or network. Why implement a non-defacto standard of secure by including it in the kernel?

I've run SELinux, and I know that James Morris isn't stating he wants that exact implementation only, but he says choose one. How do we quantify that or any assertion and make an informed decision going forward knowing that there possibly is a more secure path to follow?

Re:Spot on Torvalds... (1)

Vellmont (569020) | more than 6 years ago | (#20818287)


Security cannot be quantified in hard numbers, since security is always relative to the resources the adversary has.

I don't think anyone is asking for hard numbers for some general case. I think people are just asking for numbers for some specific cases. Lots of things in computing vary with one factor or another. I fail to see why one or many factors changing the outcome of what "best" is means you can't supply hard numbers.

Not that I think that hard numbers on which security model is really possible. I think security is a soft science because you can't really run any controlled experiments. Those kind of situations are vulnerable to "But X is better, I SWEAR!" "NO! Y IS BETTER!" since there's no way of finding out in any objective way what the right answer is.


These people should better stay far away from security-relevant decisions and let people that at least understand present technology in that area make the decisions.

I guess I see that as the height of arrogance. If you can't demonstrate why one approach is better than another to someone as technically capable as Linus, I think he's taking exactly the right approach. Maybe there is some kind of true wizardry going on here, and we should just trust you all. But I've never been comfortable with simply the "trust us!" approach to anything.

Re:Spot on Torvalds... (5, Informative)

RedWizzard (192002) | more than 6 years ago | (#20818361)

So, no, security folks are not "wanking around" as some specific asshole seems to claim, they are using the best tools available to evaluate adequacy of different security solutions. Those that do not get this are not getting what security is about and what the state of the art is. These people should better stay far away from security-relevant decisions and let people that at least understand present technology in that area make the decisions.
If you actually read the article instead of just reacting to the sensationalist quote you'd know that this is exactly what Linus is saying. Security people don't agree and he is not qualified to make a decision so modularization needs to stay. In the case of the scheduler he feels he is qualified to make decisions and has done so. However he does bemoan the fact that the arguments presented by the security experts often don't make a lot of sense. This is where the "wanking around" quote comes from.

Re:Spot on Torvalds... (2, Insightful)

QuantumG (50515) | more than 6 years ago | (#20817863)

Blah. That's a totally backasswards way of looking at it. Why do you want to make something non-modular? Other than to make it hard for people to make competing implementations. No scheduler is optimal for all applications. You either make the scheduler modular so it can be replaced easily for a given application or you settle for less than optimal performance. Linus knows this too, so I don't know what game he is playing - probably trying to lock out that scheduler implementation that he doesn't like.

Re:Spot on Torvalds... (5, Insightful)

Solra Bizna (716281) | more than 6 years ago | (#20817959)

Yeah, because modularizing the scheduler doesn't have any performance or implementation or maintainance or QA problems.

-:sigma.SB

Re:Spot on Torvalds... (1)

Kaenneth (82978) | more than 6 years ago | (#20818385)

Even Microsoft knows by now, screwing with the sceduler is a bad idea... See the Vista/Gigabit/Audio issue, where because the system thread scheduler used a different 'mode' while playing multimedia content, it caused problems with high-speed networking.

Now, if we can only kill off Daylight Savings Time. (seriously, if you want to get up an hour earlier, just GET UP AN HOUR EARLIER)

Re:Spot on Torvalds... (1)

cez (539085) | more than 6 years ago | (#20818171)

Not arguing for his reasoning of adding scheduler to kernel space, just for his viewpoint that security should remain outside it as a module. You are right, "No scheduler is optimal for all applications", but that is something we can determine. How exactly are we to determine, hey that security module is much better for application X as this one is for Y.


besides bonfire tales from the bearded ones on peyote during burning man.

Re:Spot on Torvalds... (4, Insightful)

QuantumG (50515) | more than 6 years ago | (#20818309)

Wow, Linus should go into politics. The point of the argument is that Linus refuses to make the scheduler modular. He's taken the argument that he isn't opposed to security modules being modular but he is opposed to the scheduler being modular and turned it around to say that he can't make the security modules not modular because there's no good metrics for determining which is better than the other. This is an irrelevant truth. The fact that you can measure which scheduler is better than another for a particular application supports the notion that schedulers should be pluggable modules.. so you can easily use the one which is most appropriate for the given application.

Re:Spot on Torvalds... (1)

cez (539085) | more than 6 years ago | (#20818535)

The fact that you can measure which scheduler is better than another for a particular application supports the notion that schedulers should be pluggable modules..

Ok, agreed... but, you can provide numbers to back that up. Statistics can always lie, regardless of if they are true. It's the fact that they are there and can be seen and visualized that is important. That being the case, it doesn't matter which way you lean towards schedulers. The fact that you cannot quantify security is an argument for keeping it modular.

Re:Spot on Torvalds... (0, Troll)

QuantumG (50515) | more than 6 years ago | (#20818577)

That being the case, it doesn't matter which way you lean towards schedulers. The fact that you cannot quantify security is an argument for keeping it modular.
Hehe, but that's the point. Don't you get it? Linus was asked to make an argument as to why he won't make the scheduler modular, and security modules were put forward as an example of why modular is good. His response? He explains why security modules are modular. No shit Mr Torvalds, now would you please answer the question?

Re:Spot on Torvalds... (3, Informative)

fabs64 (657132) | more than 6 years ago | (#20818633)

Did you even read the freakin discussion? The whole thing was about whether security should be modular, linus was arguing that it should stay modular, someone else was arguing that it should not and cited the scheduler as an example of linus preferring a singular option.

Re:Spot on Torvalds... (0)

Anonymous Coward | more than 6 years ago | (#20818643)

Not if pluggable schedulers negates the performance benefit of changing in the kernel without it. Compile your kernel with whatever scheduler you want if you want to be an ass about the decision to go with Ingo's.



In the end, the new scheduler is better than the one before it, and if someone has a scheduler that definitively tops CFS for a significant number of use cases, then we have something to argue about. It's regrettable that Con's never made it into Linus's tree, but it's time to move on.

Re:Spot on Torvalds... (2, Interesting)

FoxconnGuy (997669) | more than 6 years ago | (#20818649)

The key here is you have metrics to measure performance of schedulers.

I think some of the key scheduler performance metrics includes:
1. Context switch time.
2. Fair scheduling
3. Interactive tasks are interactive.
4. Certain applications always get larger portion of time if needed.
5. Real time.

There are things called "parameters" that you can adjust to adopt Linux
to your need.

This doesn't say Linux scheduler is perfect. It is evolving, too.
A few years ago, many embedded systems that needs real time scheduler
can't be implemented on Linux because timing requirements. Now the
scheduler supports real time and I can still use any applications
without knowing what the hack they have done to scheduler.

Now.

Give me an example that Linux scheduler can't satisfy your needs, and,
Give me an example that one security architecture satisfies you and me.

Re:Spot on Torvalds... (0)

Anonymous Coward | more than 6 years ago | (#20818263)

The Joy of Linux,

Blah. That's a totally backasswards way of looking at it. Why do you want to make something non-modular? Other than to make it hard for people to make competing implementations.

You can replace scheduler.o with your own implementation and reap the accolades of millions of users. Linux isn't locked by a long shot.

I retrospect, maybe all linux schedulers should be tweakable via /proc/scheduler. Sorta like Windows Control->Usage dialog box. Fuck, Unbuntu, SuSE, RedHat should all have a WorkStation/Server checkbox during install and adjust the scheduler settings for us.

Enjoy,

Re:Spot on Torvalds... (1)

Zigurd (3528) | more than 6 years ago | (#20817875)

I don't think the pluggable security model is the controversial part. The controversy is about whether measures of scheduler performance are universal, or whether responsiveness metrics are different from, say, throughput metrics.

Re:Spot on Torvalds... (0)

Anonymous Coward | more than 6 years ago | (#20817893)

He's right on?
My question is not should we add pluggable everything, but why NOT?
Is there some magical performance hit that we take when we use a different scheduler or whatever? I think the more modular the kernel is, the better.

Re:Spot on Torvalds... (1)

SanityInAnarchy (655584) | more than 6 years ago | (#20817991)

My question is not should we add pluggable everything, but why NOT?

Because that means more code to maintain. Code that might be broken later.

However, I do think there's sufficient reason to keep it pluggable. We have all kinds of other things pluggable that don't need to be, and plenty of other cruft in the kernel -- think binary formats other than ELF, old filesystems that nobody uses, and completely depricated systems like OSS for sound.

This reeks of politics, something I thought Linus was good at avoiding.

Re:Spot on Torvalds... (0)

Anonymous Coward | more than 6 years ago | (#20818163)

It's only "avoiding politics" if he agrees with you. :)

Re:Spot on Torvalds... (2, Informative)

fimbulvetr (598306) | more than 6 years ago | (#20818243)

You're right, AFAICT, but you've missed the emphasis on "more" code. From what I've read, the scheduler's tentacles touch just about every portion of vital linux code and making something "pluggable" on the order of this would require an enormous amount of effort - effort that would be pointless for all but very small minorities that can apply a patch easily.

Indeed, it's also been showing (RTFML) that scheduler improvements are mostly trivial and generally don't warrant such an effort.

Finally, one must consider that the enormous amount of bugs being introduced by touching so many different areas and applying different algorithms in different cases.

Maybe this is something for consideration with the 3.x branch (Of which Linus has no intention of making), but it seems like a reasonable decision so far given the data.

Re:Spot on Torvalds... (-1, Troll)

Anonymous Coward | more than 6 years ago | (#20817953)

I'd like to see a BUTT SEX picture of RMS fucking Torvalds UP THE ASS. I know RMS wants to, he's a sex magnet for anything that gets the rocket fired up.

So we can quantify scheduling performance? (4, Insightful)

SanityInAnarchy (655584) | more than 6 years ago | (#20817965)

I wasn't aware we'd completely solved problems of responsiveness vs throughput, or of normal vs soft realtime vs hard realtime.

If we don't keep scheduling modular, an artificial limit on the performance of the system will be created. Sure, CFS is a viable option, but why should we think it is the best ?

What's more, "wanking around with your settings" has often been what Linux has always been about. Ubuntu never uses chroot in a normal situation; does that mean it should be taken out? My GUI and hotplug utilities can automount anything I plug in; should /etc/fstab be removed?

We haven't used anything but ELF for probably 5-10 years, yet, last I checked, a.out is still supported.

Why should the system be made non-modular?

Re:So we can quantify scheduling performance? (1)

cez (539085) | more than 6 years ago | (#20818251)

If we don't keep scheduling modular, an artificial limit on the performance of the system will be created. Sure, CFS is a viable option, but why should we think it is the best ?


You are right, there always could possibly be a faster scheduler for a given system / task / embedded system.

One analogy however malformed uneducated and abysmal is:

Sure, it would be cool if you put NOS kit on a ferrari, but once you hit a wall it won't matter if you are going 150 or 225 if you aren't wearing a seatbelt or there are no airbags.

Re:So we can quantify scheduling performance? (4, Insightful)

Jah-Wren Ryel (80510) | more than 6 years ago | (#20818301)

I wasn't aware we'd completely solved problems of responsiveness vs throughput, or of normal vs soft realtime vs hard realtime.
And I don't think we ever will. I think Linus's point that scheduler performance can be measured is the strongest reason to go with pluggable schedulers. I want the scheduler that performs best for the way that I use my system. I don't think anyone gives a ratsass about how well the scheduler works for someone else. I want it to work best for me and my workloads.

Re:So we can quantify scheduling performance? (2, Informative)

mrwolf007 (1116997) | more than 6 years ago | (#20818363)

I wasn't aware we'd completely solved problems of responsiveness vs throughput, or of normal vs soft realtime vs hard realtime.

Hard realtime usually implies severe perfomance penalties. People who really need something like that probably dont use a vanilla kernel.

If we don't keep scheduling modular, an artificial limit on the performance of the system will be created. Sure, CFS is a viable option, but why should we think it is the best ?

Torvalds usually doesnt care about something being the best. Its supposed to be good enough.
Using the word best requires you to say for what, otherwise you might as well use a word such as coolest, most geeky, most whatsoever.
Since Torvalds usually cares a lot about efficiency i guess that a plugable scheduler would be less performant.

Ew, redundancy... (1)

SanityInAnarchy (655584) | more than 6 years ago | (#20818847)

has often been what Linux has always been about.

Yay for creative grammar... I apologize to anyone else who caught that. Preview is not my friend today :(

Re:Spot on Torvalds... (1)

Gorshkov (932507) | more than 6 years ago | (#20818117)

If not, an artificial limit onto the integrity of the system would be created. Sure SELinux is a viable option, but why should we think it is the best ?
Bingo.

Security is, in fact, quantifyable - you can tell if your data is or is not secure in either absolute or relative terms. But that still misses one basic, very important element .... taste.

Yes, taste *is* involved in security. Just as there are many different ways to sort data, and still wind up with an alphabeticalized list, there are also many different ways to secure your data, and still wind up with it being safe.

I don't do the dishes the same way my daughter does .... but at the end of it, when either of us is finished, they're clean.

So the SELinux folks don't do THEIR thing the same way the LSM folks do .... but who cares? At the end of the day, the dishes are still clean .. assuming, of course, a certain level of competence. But then again, if you *don't* assume that, then no security framework is going to save your hide.

I'm sorry, but I see this as a religious war along the lines of vi vs emacs. Give both camps their tools and let them do things according to their environment, level of risk, and taste.

Re:Spot on Torvalds... (2, Insightful)

kocsonya (141716) | more than 6 years ago | (#20818739)

Well, scheduling performance can only be quantified to a degree. When I'm editing a document while running two computationally and disk intensive tasks in the background (e.g big simulations) I don't really care if the background calculations will finish 5 minutes later, but I do care about the editor and every GUI thing I have on the screen being snappy, just as snappy as if there was nothing running in the background. I'm not running the latest&greatest, just some older version of 2.6.??? but that does not seem to be the case, as a matter of fact. So until the for example "perceived responsiveness" gets a firm definition and a method of quantifying it, scheduling performance is scientificly quantified only with the qualifier "..., neglecting all other factors that we can not quantify or care about."

Maybe i dont get the point (1)

mrwolf007 (1116997) | more than 6 years ago | (#20817703)

... but what would happen if you forgot to "plug in" a scheduler?
Back to single tasking ala DOS?
Being able to choose which (if any) security module to plug in seems to make a lot more sense.

Re:Maybe i dont get the point (0)

Anonymous Coward | more than 6 years ago | (#20817911)

but what would happen if you forgot to "plug in" a scheduler?

I imagine that the kernel would fail to compile at all. Presumably the rest of the kernel will expect to be able to call functions in whatever scheduler is 'plugged-in' and when the compiler goes looking for those it wont be able to find them.

Sorry, that's not a very interesting answer, but it's probably what would happen (I've never even looked at the kernel code, although I use GNU/Linux all the time).

Re:Maybe i dont get the point (1)

fadilnet (1124231) | more than 6 years ago | (#20818009)

If that is so, should there be @ least 1 scheduler provided as default? I mean, who wants to end up with an uncompiled kernel? In no time, we'll end up with different versions of kernels, forks of plugins, and we'll end up in a pit of compatibility issues. A default one can be used as part of the failsafe.

Re:Maybe i dont get the point (0)

Anonymous Coward | more than 6 years ago | (#20818237)

really, is it so hard to type "at" rather than "@" outside the context of an email address? I know, all the cool kids are doing it. NOW GET OFF MY LAWN!

Awesome (2, Funny)

obeythefist (719316) | more than 6 years ago | (#20817723)

"But the *discussion* on security seems to never get down to real numbers. So the difference between them is simple: one is hard science. The other one is people wanking around with their opinions"

Thanks Linus, that cracked me up. I've always felt that way about a lot of the stuff the security guys do. I'm gonna forward that to our local security guys and see what they think!

Re:Awesome (2, Insightful)

jofny (540291) | more than 6 years ago | (#20817821)

If they're any good, they'll agree with him...security is fundamentally subjective (what you want your box to do vs how much what you have on it is worth vs etc)

Linus is a foreigner (0, Offtopic)

megaditto (982598) | more than 6 years ago | (#20818419)

How can you trust that guy if he came here to steal all those American jerbs?

Just think how many were laid off at Microsoft alone?

Question: (0)

Anonymous Coward | more than 6 years ago | (#20817735)

If I came up with a benchmark to quantify security policies, would he:
  A. Change his mind and make security policies not pluggable?
  B. Keep security policies pluggable, but add support for pluggable schedulers to be consistent?
  C. Not change his mind, because this is just a wanker's rationalization anyway?

Best scheduler (0)

Anonymous Coward | more than 6 years ago | (#20817775)

Oh? So the debate between responsivity and throughput has finally been resolved? And we have a perfect algorithm for assigning dedicated CPUs for staged pipeline-parallel programming?

Linus may have strong opinions, but as an OS guy he should know better.

like object oriented? (1)

fadilnet (1124231) | more than 6 years ago | (#20817787)

It sure does like an object oriented approach. If the scheduler and other 'components' can be made pluggable, then it eases up the tasks of many. Developers can focus on 1 aspect of the OS, while the core kernel is just there to 'receive' the 'plugin'. How does it differ from the current approach? Are there too 'components' dependent on each other?

What does Linux Torvald know about modularity? (0)

Anonymous Coward | more than 6 years ago | (#20817905)

What makes him so big that he thinks he should control Linux? Just because his first name is the same?

please type the word in this image: frontal [lobotomy???]

Cold Hard Engineering Measurement, or Science? (2, Interesting)

Alexander (8916) | more than 6 years ago | (#20817909)

I think Linus may want to think hard about creating a distinction there.

``...the subjectivist states his judgments, whereas the objectivist sweeps them under the carpet by calling assumptions knowledge, and he basks in the glorious objectivity of science.'' - I.J. Good

I stopped reading TFA (2, Interesting)

kwabbles (259554) | more than 6 years ago | (#20817975)

The moment I saw the word "scheduler".

Damn I'm sick of scheduler FUD. It makes its way into every single linux conversation now, now matter how unrelated.

Re:I stopped reading TFA (0)

Anonymous Coward | more than 6 years ago | (#20818387)

Dude, the process scheduler is one of the most essential parts of an operating system kernel. And with typical systems these days having at least a dual-core CPU, the scheduler becomes even more important. So the scheduler being used is something we have to keep in mind at all times when doing kernel development. Even as users, we need to know which schedulers are best for certain situations. That's how we can maximize the performance of multicore systems.

Re:I stopped reading TFA (3, Funny)

Dr. Evil (3501) | more than 6 years ago | (#20818737)

You'll reprioritize when your starving children become zombies and your parent tries to kill you.

yawn (1)

kennedy (18142) | more than 6 years ago | (#20818049)

c'mon - this is open source.

why not have both? linux-smack and linux-selinux could co-exist. fork the kernel and find some people to maintain an selinux fork - there has to be some out there if there's front-page worthy drama going on...

How's THAT for a pluggable security model?!

(yeah i rtfa'ed... lulz)

Language abuse (1)

midnighttoadstool (703941) | more than 6 years ago | (#20818055)

"Wanking" is rough-slang English from England, and means 'masturbating'. But Torvalds sure ain't one of us.

Re: reply from an American... (0)

Anonymous Coward | more than 6 years ago | (#20818483)

Bugger off, ya bloody, spastic, wanker. Outside of England, all your sodding curse words arse [sic] just +funny to everyone else. So stop trying to shag the language everybody else uses -- that's just naff. Did I mention you're cheeky shite-bunging monkey. Oh yeah, and Bob's your uncle! Cheerio!

Re:Language abuse (2, Funny)

theNeophile (238938) | more than 6 years ago | (#20818527)

"Wanking" is rough-slang English from England, and means 'masturbating'. But Torvalds sure ain't one of us.
All of the other words he used also come from England. How dare he!

If you read all of it ... (5, Informative)

golodh (893453) | more than 6 years ago | (#20818085)

Perhaps if people read all of Linux's email they would be more understanding and less quick to condemn him.

His complete email reads:

Schedulers can be objectively tested. There's this thing called "performance", that can generally be quantified on a load basis.

Yes, you can have crazy ideas in both schedulers and security. Yes, you can simplify both for a particular load. Yes, you can make mistakes in both. But the *discussion* on security seems to never get down to real numbers.

So the difference between them is simple: one is "hard science". The other one is "people wanking around with their opinions".

If you guys had been able to argue on hard data and be in agreement, LSM wouldn't have been needed in the first place.

BUT THAT WAS NOT THE CASE.

And perhaps more importantly:

BUT THAT IS *STILL* NOT THE CASE!

Sorry for the shouting, but I'm serious about this.

Al I alone in thinking that Linux basically says:

"Look I'm no security expert, and I'd be happy to follow your collective expert guidance if only:

(a) you could quantify what you're saying and turn it into engineering instead of a religious argument

(b) the lot of you could agree on *one* set of guidelines/features as being best all-around

Unfortunately it appears you can't do either. That being so, I'm not going to burn my fingers and blindly choose one security boondoggle over all the others. I'll just make them pluggable so that every one of you can have his own personal security system. End of discussion. Now go away and be happy."

Torvolds declares war on physicists! (1)

NemoinSpace (1118137) | more than 6 years ago | (#20818465)

You're acting like a string theorist, claiming that there is no other viable theory out there. Stop it. It's been going on for too damn long.
I read as much as I could, till I realized Linus was going to go off on another tirade on people who are presenting their arguments to him. He starting to make Balmer look reasonable.
Go ahead, piss off the physicists - Now _everyone_ will stop using linux. :)

Re:If you read all of it ... (1)

TubeSteak (669689) | more than 6 years ago | (#20818521)

FTFA

LSM's weak semantics and pervasive deep hooking of the kernel means that
> we'll have to continue dealing with several unpleasant issues, such as the
> abuse of the API by out of tree vendors,
Exactly what kind of API abuse are they talking about?

Re:If you read all of it ... (1, Interesting)

Anonymous Coward | more than 6 years ago | (#20818787)

I'll never understand why Linus Torvalds can belittle the developers contributing to the kernel and be praised as a passionate and pragmatic engineer while Theo de Raadt gets schoolyard insults hurled at him every time he voices an opinion (which is admittedly quite often, but no more often than Mr. Torvalds).

This is a quintessentially pragmatic decision (if you can't get people to agree make it so that everyone can make the decision for him or herself) but done in what I feel is very rude manner. Look back at many decisions made around OpenBSD, especially as they relate to security policy, and you'll see the same thing.

The "let everyone decide for themselves" mentality is also very different from the stance Mr. Torvalds took on choosing GNOME over KDE ("The GNOME attitude is a disease. Just tell people to use KDE.") In that case he displayed exactly the hubris Mr. de Raadt is constantly accused of.

So at the end of it all, please tell me: Why do two people with very similar attitudes get labeled by the community so differently?

No, he is right on one thing (0, Flamebait)

mdenham (747985) | more than 6 years ago | (#20818209)

Yes, one is hard science, and the other one is people wanking around with their opinions. Specifically, the security one is hard science, while the scheduler is the wanking.

Good. (0, Offtopic)

crhylove (205956) | more than 6 years ago | (#20818225)

I agree with hard science. Here's some more hard science:

The kernel kicks ass.

We need better apps for Linux.

I can't videoconference, edit videos, make mp3s, play video games or make a slideshow in Linux. How about a couple of kernel devs drop off and help Linux go the last mile.

rhY

Re:Good. (1)

webmaster404 (1148909) | more than 6 years ago | (#20818319)

Well I agree that there needs to be better applications for Linux, however your reasons are incorrect. I don't know of an application for videoconferencing off the top of my head because I don't use that, for editing videos try KDENLIVE http://www.kdenlive.org/ [kdenlive.org], for MP3s thats simply a patent restricted format, just tell your government to reject software patents, for video games try to run your windows games in WINE and there are many Linux games, try some of those, just because its not 3-D doesn't mean that its bad. And OOo has a sideshow presentation software included with it.

Re:Good. (2, Informative)

NullProg (70833) | more than 6 years ago | (#20818365)


I can't videoconference, edit videos, make mp3s, play video games or make a slideshow in Linux. How about a couple of kernel devs drop off and help Linux go the last mile.


Other than video conferencing (haven't tried), my wife and 13 year old son can do everything on your list (using SuSE, Fedora or Ubuntu).

Shouldn't you be posting questions to http://www.linuxquestions.org/ [linuxquestions.org] or http://www.justlinux.com/ [justlinux.com] ?
You wont get a RTFM response.

Slashdot isn't a Linux help forum.

Enjoy,

Bring deRaadt in for a consult (2, Funny)

e9th (652576) | more than 6 years ago | (#20818255)

I mean, Theo's the security guy, right? I'm sure Linus would have no problem whatsoever agreeing to abide by his decision...

Re:Bring deRaadt in for a consult (0)

Anonymous Coward | more than 6 years ago | (#20818731)

ROFL. You just made my day there.

Linus is right (0)

Anonymous Coward | more than 6 years ago | (#20818471)

I am with Linus on this one. For the life of me I can't understand what this sucking up to RMS is about. Linus himself does not think GPLv3 is a good thing. So why do people keep adopting it.
Without Linus FOSS is tossed. Not following Linus is dangerous for the survival of FOSS.

Scheduler vs Security Plugins (2, Insightful)

NullProg (70833) | more than 6 years ago | (#20818769)

Correct me if I'm wrong, wouldn't a security plugin have to be authenticated? That would add a couple of extra layers not required for a scheduler. A "Rock Solid" built in security scheme might be better (Unlike the Windows address relocation method). Linus is correct in the fact that there is a new security method every week. Whats the correct one to choose?

As for the Linux scheduler, I wouldn't mind a choice in desktop vs server tweak settings in (a) /proc/sys/scheduler (if it existed). RedHat, Ubuntu, SuSE, etc. could set the defaults based on user selection at install (Work Station vs Server).

Enjoy,
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