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Bad Lockup Bug Plagues Linux
jones_supa (887896) writes "A hard to track system lockup bug seems to have appeared in the span of couple of most recent Linux kernel releases. Dave Jones of Red Hat was the one to first report his experience of frequent lockups with 3.18. Later he found out that the issue is present in 3.17 too. The problem was first suspected to be related to Xen. A patch dating back to 2005 was pushed for Xen to fix a vmalloc_fault() path that was similar to what was reported by Dave. The patch had a comment that read "the line below does not always work. Needs investigating!" But it looks like this issue was never properly investigated. Due to the nature of the bug and its difficulty in tracking down, testers might be finding multiple but similar bugs within the kernel. Linus even suggested taking a look in the watchdog code. He also concluded the Xen bug to be a different issue. The bug hunt continues in the Linux Kernel Mailing List."
You Lunix lusers!
I'm not telling anyone, though. Linus was mean to me.
This was predicted!
It's linux, it's supposed to suck
Oh. And sure, when things crash and you fsck and you didn't even get a
clue about what went wrong, you get frustrated. Tough. There are two kinds of reactions to that: you start being careful, or you start whining about a kernel debugger.
Quite frankly, I'd rather weed out the people who don't start being
careful early rather than late. That sounds callous, and by God, it _is_
callous. But it's not the kind of "if you can't stand the heat, get out
the the kitchen" kind of remark that some people take it for. No, it's
something much more deeper: I'd rather not work with people who aren't
careful. It's darwinism in software development.
I've been a Linux user for a long time. I first got into it back in the Windows 95 days, because Linux was totally stable, while Windows crashed on me several times a day. But now my modern Linux experience is so much like my Windows 95 experience was, and this saddens me.
I couldn't even get recent versions of Fedora to boot on my computer. And this is a computer that ran Linux Mint, Ubuntu and Debian just fine! Linux Mint's quality has gone downhill lately, too, but I think that's just because Ubuntu's quality has gone downhill. I was most recently using Debian, but my computer got messed up after I did an update and that SystemD thing got installed.
I haven't been happy with other developments, either. I used to love GNOME 2, but I tried GNOME 3 and it was like using Windows 8. It's just a bad and dumb experience.
I don't know what to do at this point. I can't keep using Linux if its stability is crap, and the other major open source software is caca these days. I don't want to switch to *BSD. I don't like Windows at all. So I think maybe I'm just going to sell my computer, and buy a Mac.
> The patch had a comment that read "the line below does not always work. Needs investigating!" But it looks like this issue was never properly investigated.
I thought open source software was supposed to be better because everyone could see the code and spot problems.
The last mail in the thread, dated the 26th of November, explains that the Xen bug was a Xen bug and that the lockup was something different and traceable once the chap experiencing the bug managed to get a kernel backtrace.
Trying to become famous by taking photos. Visit my homepage please.
This is good for open source.
it is that systemd thang
say no to systemd
do not put your hands up and do not say i am not resisting
you must resist
you must fight back
you must disable
you must destroy
fight the good fight
kill all that is evil
If you aren't paying, you are the product.
This bug has been plagueing it since the early 90s. Namely, that it sucks.
Who will fix that, because Torvalds is obviously not up for the job.
Can confirm it happens in 12.04
> First got into it ... because Linux was totally stable
If stable is your top priority, Fedora is approximately the worst possible choice. Fedora is essentially Red Hat Beta. If you want stable, the devel / beta branch is not for you. You'll probably be much happier with Red Hat or its twin, CentOS.
Also, you mentioned that you did an "upgrade" to Debian Unstable. You didn't mention any _reason_ for doing that. If stability is a top priority for you, don't upgrade just because you can, don't fix it if it aint broke.
Mac OSX may indeed be a good choice for you also. It is certified Unix and if you use the commondand line in Linux you'll find that day-to-day tasks are the same on a Mac. System internals are different of course, but bash, sed, awk, grep, and vim work just like they do on Linux.
> If Will's patch doesn't make a difference, what about reverting that
> ce9ec37bddb6? Although it really *is* a "obvious bugfix", and I really
> don't see why any of this would be noticeable on x86 (it triggered
> issues on ARM64, but that was because ARM64 cared much more about the
> exact range).
That's alright then. No one uses AMD any more.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
Systemd rears it's ugly head...
not graduate students who pose in front of a mirror daily and yell at people...
So it may be a "bad" lockup bug in the sense that nobody knows exactly what causes it, but it's not "bad" in the sense that people should worry overly.
Why?
Dave Jones sees it only under insane loads (CPU loads of 150+) running a stress tester that is designed to do crazy things (trinity). And he can reproduce it on only one of his machines, and even there it takes hours. And it happens on a debug kernel that has DEBUG_PAGEALLOC and other explicit (and complex) debug code enabled. And even then the bug is a "Hmm. We made no progress in the last 21 seconds", rather than anything stranger.
In other words, it's "bad" in the sense that any unknown behavior is bad, but it's unknown mainly because it's so hard to trigger. Nobody else than core developers should really care. And those developers do care, so it's not like it's worrisome there either. It just takes longer to figure out because the usual "bisect it" approach isn't very easy when it can take a day to reproduce..
This can only mean one thing: not enough systemd. systemd needs to expand much further and start replacing the Linux kernel itself to ensure this kind of thing won't happen.
If they hadn't written this crappy code, this wouldn't have happened.
Operating systems can be written by anyone who wants to, dumbass.
BSD machines xmembers are
> OS X may be stable but it has a short shelf life. You might find your hardware unsupported in 3 or 4 years
I don't know if that might be true of some iOS mobile devices or where that FUD comes from, but my six year old Mac from 2008 is going strong and I just installed an OS update. My employer wanted to replace it, but it's a quad core with16GB of RAM - more than sufficient for today's software. Bureaucracy said the budget had to be spent on computer equipment, so we upgraded one of the four drives to an SSD. The old RAID was fast enough, but I guess the SSD will save a few minutes per week. Later we used the budget to add a Macbook Pro. It will probably make sense to upgrade my desktop in 2015 or 2016, when it's seven or eight years old.
That's the perspective of a guy who isn't even paying for the upgrade. It's free to me, but if I can run the latest OS and multiple IDEs and browsers open on four monitors with no noticeable lag, why would I replace it?
Here I am, still going strong when the last reboot of this XP machine was weeks ago, and once again Linux gives us a perfect example of why the joke of an OS (for mainstream use) will never change.
This XP machine always gets freaky as its uptime reaches weeks (due to the terrible data structure and memory management techniques employed by Microsoft) but doesn't go down. When the 'creakiness' gets too bad (resource issues causing windows elements to not render- but WITHOUT lock-ups), then it's time to reboot- but XP is one hell of a reliable workhorse.
The dysfunctional nasties that tend to be the core developer base for Linux and associated software are 100% responsible for failing to make Linux even a decent replacement for XP- Microsoft's greatest STANDING TARGET. Go to ANY Linux code development forum, and see how long you can read the posts before wanting to PUKE. The attitude of most Linux developers STINKS worse than a warehouse of fish six months after the cooling system has failed.
You will read reasonable user request after reasonable user request for trivial and necessary fixes DISMISSED by the dysfunctional scumbag developers under the excuse that THAT post referred to version 23.11223 and developers only now listen to issues referring to version 23.11224. Literally, the current version number is used as the EXCUSE to dismiss every user issue with the product, regardless of whether a newer version contained ANY attempt to fix the issue.
The average Linux developer is a SOCIOPATH for whom the 'gaming' of users with such semantic nonsense is all the fun.
ALL the time I hit a bug in one of these projects- Google it and find other with the same problem YEARS ago. But the 'bug report' has been CLOSED DOWN by scumbags quoting the version number trick- while the bug persists, of course, in the latest version.
Linux people LOVE excuses. A 'good' excuse is BETTER than responsible coding any day, in the world of key collaborative open-source projects. And now, worse, frontline Linux development is obsessed with matching Microsoft gimmickry in Win8/8.1 and Win10. Forget about an open-source OS that just works- oh no! Linux is fully lost in the lunacy of OS as the main frontline app experience of the user (see Android/Win8.1 for the worst of this philosophy).
Of course, lying just below the surface of Microsoft's Win8.1 is a better XP- which means people CAN lean on this OS. What the hell does Linux give the general user?
PS in the UK yesterday, in a major supermarket chain, you could buy an 8" FULL win8.1 tablet with first quality display running on a BAYTRAIL quad-core Intel SoC (with free Office I think) for 80 quid. Take it from me- these FULL Windows tablets make ever other type of tablet a COMPLETE joke. Years after Linux had its ONE widespread success via the niche of Android on low cost tablets, Microsoft and Intel has come along and smacked Linux into oblivion (Google just doesn't know it yet).
Here's the thing. This WONDERFUL cheap tablet is the ONLY tablet in existence (save for other full Windows tabs, of course) that can simply SEE all your files on your NAS and use such files in whatever desktop app you so wish. That's right- want to watch a video on the Linx 8? Simply install DESKTOP VLC player, open the file browser, select the film on your NAS, and tap the 'open' option.
LINUX (Android) doesn't even let you install apps on your external SDcard any more. It certainly will NEVER allow you to 'see' shared file resources on something like a NAS. Oh, no- the Linux clods insist you must install MEDIA SERVER software that treats all files as OBJECTS - objects that must be REGISTERED with specific apps.
Two years ago I thought Android and Arm would kill Microsoft and Intel. But it turned out Android was terminally infected with the Linux cancer. So Android today plays SCREW THE USER, and Win8.1 on a cheap tablet does NOT.
Yes, Microsoft is giving away Windows on the tabs (called Bing Windows 8.1- but it is still a FULL version of 32-bit
This is but the price we pay for not dedicating an entire core to systemd. If systemd did not have to share a core with the other processes, then it would be free to seek out and steril...correct these trifling kernel issues and the ones responsible.
I don't know if that might be true of some iOS mobile devices or where that FUD comes from, but my six year old Mac from 2008
Well, I guess if Yosemite runs on YOUR six year old Mac you must be right, and anything anyone else says must be FUD.
Then again, OSX March was released in 2013, and dropped support for early-2009 13-inch Mac Book Pros.
So, just to make it perfectly clear to you, they've ALREADY dropped support for a laptop that's a year NEWER than your computer, being dropped by OS that's already a year and a half old.
Mavericks (and Yosemite) also dropped support for any Xserve's older than 2009 (so server class hardware got dropped after just 4 years of support), and any mac mini's older than 2009 got dropped as well.
Millions of Macs from 2008s stopped being supported over a year and half a go. You got lucky.
Since every bug this year needs to have a catchy name for the headlines, I propose we call this one "Davy Jones' Lockup."
I almost pissed myself laughing at this
Well, I guess if Yosemite runs on YOUR six year old Mac you must be right, and anything anyone else says must be FUD.
FUD is when people made false statements to try to prove their point. As an example of FUD, here's your statement:
Then again, OSX March was released in 2013, and dropped support for early-2009 13-inch Mac Book Pros.
I'm assuming you made an error and meant OS X Mavericks, not OS X March? Even if so, you're absolutely wrong. Mavericks and Yosemite can run on any MBP (Macbook Pro) from 2007 on. So, maybe you made a second typo and had really meant 2009 MacBooks (not Pros)? Alas, Mavericks/Yosemite (they have the same system requirements) will run on early-2009 Mac Books, as well. So, you're basically just entirely wrong. Here's the Apple support page if you don't believe me: http://support.apple.com/en-us/HT6412.
I do think it's worth noting that the Intel macs that are not supported are either 32-bit only or computers with 32-bit EFI. Mavericks and Yosemite are 64-bit only, so the 32-bit processors computers are out. Most of the Macs with 32-bit EFIs can easily run Yosemite, albeit not officially. I'm running Yosemite on my 2006 Mac Pro 1,1. It runs great and was very easy to install.
So, just to make it perfectly clear to you, they've ALREADY dropped support for a laptop that's a year NEWER than your computer, being dropped by OS that's already a year and a half old.
Nope. Apple has in no way "dropped support" for any laptops still under warranty or support contract. They merely do not support the older Macs with the latest version of the Operating system. The minimally supported systems are still at least 4-5 years old and 7+ years old in many cases (like my own). Works for me.
Mavericks (and Yosemite) also dropped support for any Xserve's older than 2009 (so server class hardware got dropped after just 4 years of support), and any mac mini's older than 2009 got dropped as well.
Apple dropped the Xserve entirely--they stopped selling Xserves and announced the end of the line, what, 4 years ago? Too bad, IMHO, but announced and expected.
So,
I guess he is human after all.
Go figure...
Hardlockup... Bluescreen...
Is there a difference?
Well, has he tried it?
I'm assuming you made an error and meant OS X Mavericks, not OS X March?
Yes, Mavericks. Not sure what freudian slip caused that.
Even if so, you're absolutely wrong. Mavericks and Yosemite can run on any MBP (Macbook Pro) from 2007 on.
http://support.apple.com/en-us...
Ok, that's interesting.
Now Check:
http://support.apple.com/en-us...
"
MacBook Pro (13-inch, Mid-2009 or later),
MacBook Pro (15-inch or 17-inch, Mid/Late 2007 or later)
"
They are explicitly excluding the early 09' and earlier MBP 13" with Mavericks, while Yosemite doesn't mention that.
Now I'm curious if its actually supported by Yosemite or not.
Most of the Macs with 32-bit EFIs can easily run Yosemite, albeit not officially. I'm running Yosemite on my 2006 Mac Pro 1,1. It runs great and was very easy to install.
I hear you, but being able to make it work, and it being supported are worlds apart. Apple dropped support for it. Its not pleasant being in that position, even if you can "make it work".
Apple dropped the Xserve entirely--they stopped selling Xserves and announced the end of the line, what, 4 years ago? Too bad, IMHO, but announced and expected.
People buying servers do not expect support to drop that quickly. Just because apple disco'd producing the line doesn't mean that support for the ones they did sell should end quicker.
Nope. Apple has in no way "dropped support" for any laptops still under warranty or support contract.
Nobody said they did. But many computers 4 years old were not being supported when mavericks came out. That's all the OP claimed, and all I confirmed.
Bottom line, with Apple once the apple care runs out, your guess is as good as mine whether anything that comes out thereafter will be supported on your system. It might be. It might be something you can shoehorn on yourself without official support. Or it might not be at all. That's not FUD.
I'm no saying other vendors or that OSS is necessarily better, but lets not put Apple on a pedestal and say that it IS better. Because its really not.
Apple dropped the Xserve entirely--they stopped selling Xserves and announced the end of the line, what, 4 years ago? Too bad, IMHO, but announced and expected.
You're server-ing wrong. Servers should be cycled out after three years, and they should only be non-RAID, non-redundant-power, non-ECC-Reg RAM, non-VGA, non-rack-mount Mac Minis. It's the Apple(TM) way.
have you checked the children??
android and chrome OS are shaping up as windows alternatives. I just bought a powerful computer running chrome OS, and it only cost 160 dollars.
http://www.sonnettech.com/prod...
You're mounting that mac wrong.
Computer support in a nutshell: blame the user.
It's accurate 99% of the time.
And it's really irrelevant to getting it fixed. If you're running Windows, go to Best Buy and ask them. Mac OS, go to an Apple store. Linux does not have either option. Especially if you stray outside the narrow realm of the well-supported, you can either be an active part of the solution or find a different OS. No one is trying to be mean or disrespectful by saying so, there simply is no alternative. This is more or less by design: almost all Linux projects will avoid anything that reduces the power of the experienced user. This doesn't always conflict with empowering novice users, but no one is going to lose sleep if it does happen.
Linux is my desktop. Directly and indirectly I contribute very little if anything to its development. For better or worse, Linux development is driven by the Android, embedded, server, and supercomputing sectors, not the desktop. If you come to Linux with the idea that it is desktop-focused and that you do not have any responsibility to debug or fix it when it breaks, please in all sincerity do yourself a favor and use a different OS. Linux may be stable enough for your use case today, but if you only know how to handle it when it's working perfectly, that 1-in-100 bug will cancel out every good experience you've ever had and then some.
Find a distro that lets you force what you want and upgrade what you need.
I have a Gentoo install that is 8-10 years old that I've just upgraded piecemeal as the needs arise.
Unlike the ubuntu install I have alongside it (mostly for when I need stuff *NOW* and I happen to not already have it installed on Gentoo), I can be a lot more forceful with avoiding package upgrades, and it in addition has a lot of multi-version work done to allow, for instance, AMD/Nvidia/Mesa graphics drivers all installed at the same time with quick and easy swapping between them (this is a power user feature since not remembering to switch them when you change drivers can lead to headaches if you haven't experience them before.), as well as gcc, binutils, python, and a dozen other packages, where you may have software expecting a default version of a scripting language or dev utility that wouldn't be available on a binary distro, since they tend to follow the 'moving target' development philosophy.
That said: Linux is just a tool in your toolbox, if it stops doing a good job at what you need, migrate your data or ensure filesystem compatibility and move to another OS. With the exception of the Gentoo box I've got through a few distro changes over the years, either do to hard disk upgrades (might as well try a different OS while I'm migrating partitions anyways), or do to annoyances with some feature changes (Redhat/Fedora/SuSE I'm looking at you!)
In the end Ubuntu had the best package support in Launchpad for the random stuff I'd like to install, while gentoo made it easy to work around the whole package mess with ebuilds, layman, and the ability to force things even if gentoo thought it would break things or cause dependency hell. While it might seem counterintuitive, many times it's provided more productivity than ubuntu, especially when I needed bleeding edge or legacy packages which otherwise weren't available.
In regards to the kernel upgrades: Keep backups of old versions when you upgrade, or if you have /proc/config(.gz) available, compile your own from vanilla or patched sources with the default distro config. In the case of gentoo, I still have 2.4 kernels available until udev forced a change (which by the way hosted support for 2.6 kernels before .18 or so. I forget the exact version that devfs was completely eliminated and the migration to udev forced.)
Hey Linux fanboys, I have about a dozen Windows machines I use regularly, haven't had one lock up on me in at least five years.
Good old AAPL and M$FT Fear, Uncertainty, Doubt. Nothing innovative.
Yeah, your shareholders expect perpetual growth at 5% or more. Until the entire Universe belongs to AAPL or something.
The truth is - Linux is stable and secure as it has ever been*. I have been using it for the last ten years and I saw absolutely no need to go back to Windoze or MacOS. All the antics of you CORPORATE SLEAZEBAGS actively discourage me from doing so.
Very soon the Manic Growth Imperative will mandate I can only use AAPL printers, AAPL mice, AAPL-supplied music on a Macintosh computer, correct ? And if it is older than 7 years, SSL bugs wont be fixed - buy a new computer already, CONSUMER.
* dont expect it to be NSA-safe, though. They have penetrated everything popular, including Linux.
Linux had appstores anbd centralized Update before AAPL coined the term. We have sandboxing mechanism which are apparently still some kind of secret in the rotten Commerce-Wold of M$FT.
Let me repost this:
Good old AAPL and M$FT Fear, Uncertainty, Doubt. Nothing innovative.
Yeah, your shareholders expect perpetual growth at 5% or more. Until the entire Universe belongs to AAPL or something.
The truth is - Linux is stable and secure as it has ever been*. I have been using it for the last ten years and I saw absolutely no need to go back to Windoze or MacOS. All the antics of you CORPORATE SLEAZEBAGS actively discourage me from doing so.
Very soon the Manic Growth Imperative will mandate I can only use AAPL printers, AAPL mice, AAPL-supplied music on a Macintosh computer, correct ? And if it is older than 7 years, SSL bugs wont be fixed - buy a new computer already, CONSUMER.
* dont expect it to be NSA-safe, though. They have penetrated everything popular, including Linux.
Let me repost this:
Good old AAPL and M$FT Fear, Uncertainty, Doubt. Nothing innovative.
Yeah, your shareholders expect perpetual growth at 5% or more. Until the entire Universe belongs to AAPL or something.
The truth is - Linux is stable and secure as it has ever been*. I have been using it for the last ten years and I saw absolutely no need to go back to Windoze or MacOS. All the antics of you CORPORATE SLEAZEBAGS actively discourage me from doing so.
Very soon the Manic Growth Imperative will mandate I can only use AAPL printers, AAPL mice, AAPL-supplied music on a Macintosh computer, correct ? And if it is older than 7 years, SSL bugs wont be fixed - buy a new computer already, CONSUMER.
* dont expect it to be NSA-safe, though. They have penetrated everything popular, including Linux.
Man, cant you think of those filthy rich AAPL shareholders ? They expect to become 5% richer every year for the next 25 years based on a new Macintosh being pushed to CONSUMERS every three years. Or better, every fiveteen months. And every nince months a new iPhone. You REALLY have to care about THEIR GROWTH !
Show some responsibility, work harder in the salt mines and GET YOURSELF CREDIT TO BUY A NEW AAPL MACHINE !
Linux - that's COMJUNIZM !!!!!
...because you dont support the noble American Monopolist Companies like M$FT and AAPL. Your communism shows because your dont want to scrap your three year old computer. Clearly !
...and their Android Devices Support Your Argument, Mr Burson-Marsteller.
Break the news to Nutella already: The War Is Lost. Linux has won !
Is a bunch of Sleazy Monopolists.
.....
http://lwn.net/Articles/430098/
Guess that destroys your pathetic atempt to lie. Seriously, my five year old tells better lies than stamping his foot and saying "NO!"
Proof:
http://koblents.com/Ches/Links/Month-Mar-2013/20-Using-Goto-in-Linux-Kernel-Code/
whoooooosh
obviously, but that doesn't mean everyone should. that's what the gp meant. critical or popular software should be written by professionals.
If you're using Xen - which is a virtualization package. I've never run across Xen in the wild - in fact only at one job interview did they actually use Xen.
They are explicitly excluding the early 09' and earlier MBP 13" with Mavericks, while Yosemite doesn't mention that.
Now I'm curious if its actually supported by Yosemite or not.
Hmmm... that is interesting. I have checked, but I image some mackintosh forums would be the place to know for sure. In either case, we're talking about a less than one year difference, so not huge either way.
I hear you, but being able to make it work, and it being supported are worlds apart. Apple dropped support for it. Its not pleasant being in that position, even if you can "make it work".
Fully agreed--I wish Apple would have included the EFI compatibility shims. I think this--MacPro 1,1--is a perfect example of Apple doing something badly.
But many computers 4 years old were not being supported when mavericks came out. That's all the OP claimed, and all I confirmed.
Perhaps "many" for small values of many. The majority of all Intel mac models support the latest operating system, even post–Mavericks. The only exceptions are:
1) single core processors
2) 32-bit only processors / EFI
3) a very few unsupported graphics cards
Bottom line, with Apple once the apple care runs out, your guess is as good as mine whether anything that comes out thereafter will be supported on your system. It might be. It might be something you can shoehorn on yourself without official support. Or it might not be at all. That's not FUD.
Bottom line, with Apple once the apple care runs out, your guess is as good as mine whether anything that comes out thereafter will be supported on your system. It might be. It might be something you can shoehorn on yourself without official support. Or it might not be at all. That's not FUD.
Barring a few major architectural shifts (68k-PowerPC, PowerPC-Intel, 32-bit–64-bit), Apple tends to support computers for a long time. If you're unlucky enough to be an early with low-end hardware, you might miss out. This is true, and a valid complaint. This should not be over-generalized, however!
I do not believe it's fair to say OS X has a "short shelf life" as stated by the GP (unless meaning that new versions are released frequently).
I'm no saying other vendors or that OSS is necessarily better, but lets not put Apple on a pedestal and say that it IS better. Because its really not.
I would never say Apple is better than OSS in terms of support. The FreeBSD dev lists have been discussing some pty changes recently, and one of the mandates was maintaining jail support for FreeBSD 4 released in 2000. Other kernel options extend binary compatibility back probably to 20 years before that! You're not going to beat that. Apple certainly isn't going to even try.
FWIW, Yosemite runs faster on my 2007 macbook pro than Mavericks did (and I hated Mavericks).