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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."
It is a Genuine Advantage!
It is, they can and do.
I don't care why you're posting AC
That's why having a bug is worthy of a news item.
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.
I thought open source software was supposed to be better because everyone could see the code and spot problems.
Too often when I find a bug (even investigate the actual reason as well as I can) and talk about it in a mailing list or bug tracker, it's just crickets chirping. No one stands up and properly takes responsibility of the issue. I very well understand that this might be due to lacking developer resources, but it still results in bad software.
I have started wondering if modern software is simply too complex to be developed in high quality with the resources (manpower and funding) that open source gets.
This is not unique to open source software. Closed source code also is complex, and lacks developers. Bugs that aren't reported by big customers are easily ignored.
Linux support in a nutshell: blame the user.
I don't want to switch to *BSD..... and buy a Mac.
So which is it? I got introduced to Linux because I had a Mac. I first started messing around with Terminal.app and it's gone from there. After a botch attempt at Linux on a generic laptop and hating having to deal with finding GNU Tools for Windows I'm thinking of going back.
It has a UI that "just works" and I don't have to dick around with settings. Even IPv6 is very easy to set up with a lot of brokers straight from the Network settings. But it also has gcc, clang, make, etc that makes life easier for doing development.
In my experience, closed source software comes with much less bugs to begin with. With OSS, even some essential features can be glitchy or partially implemented.
While I'd agree that much open source software is just hacked together and shipped when it does everything the developers care about, most of the bugs in our software (not open source per se, but our customers get all our source so they can modify it if they want) are caused by third-party, closed-source libraries that we use because licensing them was much cheaper than writing the same code from scratch. I haven't seen a single crash in a year that wasn't due to third party, closed source code.
And, financially, it still makes sense, because developing workarounds for their bugs is still cheaper than writing the code from scratch.
It's not systemd related, you can check by opening a termin
Mod me down, my New Earth Global Warmingist friends!
> 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.
So are you saying they failed your genuine advantage check?
Mod me down, my New Earth Global Warmingist friends!
Get an operating system whose kernel works. OpenBSD.
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..
Ubuntu keeps updating the 3.13 kernel with a patch queue (their own kernel version is currently 3.13.0-40.69), so if one of those patches contain the bug, there's an unlikely but theoretically possible chance that Ubuntu kernel might have become faulty too.
I blame systemd anyhow. The growing use of systemd is also the primary cause of global warming, and the declining honeybee population.
Socialism: a lie told by totalitarians and believed by fools.
Have you ever compared enterprise class software (I also count Windows 7 Enterprise) with OSS Software? Windows does not even reliably support STR and resume. Using multiple monitors is a PITA.
Suspend and multiple monitors have always worked great in Windows for me. Under Linux, they have also worked fine in some machines, but I have also occasionally experienced serious problems with those areas. During recent times I have found out that even laptop screen brightness adjustment cannot be expected to work reliably out of the box under Linux.
> 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?
I think the answer to that one is "all over the map". Certain aspects of open source are done with excessive attention to niche functionality because there's either funding or the kind of geeky details that have nerds jumping all over it to implement. Other features, particularly features you'd use if you're a... less than tech-savvy user, tend to be ignored. Obligatory XKCD. On the bright side, it's not like code actually rots so the resource problem can be rephrased as how quickly does the environment change with new hardware and languages and libraries and standards and protocols and so on. Not to mention input paradigms like multi-touch versus keyboard and mouse. Eventually it has to slow down. PCIe has existed longer than any of the standards that preceded it. USB has lasted longer than than the standards that preceded it. H.264 has lasted longer than any of the standards that preceded it. Now we've got computers that can fit into the palm of our hands, how much smaller and different could they get? I guess sci-fi isn't out of ideas yet but if keyboard and mouse has gotten us through the last 30 years I expect touch to last longer and what follows touch even longer.
Another perspective is simply considering if the users' needs are going to rise infinitely, which I suppose is a special case of the above. Just because Photoshop continues to add features doesn't mean that people need photo editing of infinite complexity. It might simply be that once you've reached a certain level of functionality open source is good enough for most people on a fairly permanent basis. I know at least a few tools that I more or less consider "done", like just recently I installed Babaschess which was last updated in 2007, it's abandoned yet fully functional. I have QuickPar installed, which hasn't been updated since 2004 yet I also consider "done". With open source people like to fiddle with it but there as well there's software which has been essentially unchanged for years. The pace might be glacial at times but ultimately I think open source will win out. Just look at Linux/BSD, Windows is the only one with a homegrown kernel and I suspect that's mostly history. I doubt Microsoft would start writing another kernel from scratch today.
Live today, because you never know what tomorrow brings
Since every bug this year needs to have a catchy name for the headlines, I propose we call this one "Davy Jones' Lockup."
I was most recently using Debian, but my computer got messed up after I did an update and that SystemD thing got installed.
Yeah, Debian totally jumped the shark with Jessie. A bunch of stuff broke on my machine - I suspect it was systemd. Couldn't go back to Wheezy though - I bought a new MoBo, and Wheezy didn't even support the *wired* LAN connection out-of-the-box.
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 never even tried G3 - the screen shots and reviews were enough to keep me away. I switched to XFCE at that point, and I've been pretty happy with it. The file manager is only adequate - but then there are no really good graphical file managers in Linux, and I've learned to live with Thunar's limitations. (Dolphin came close to being as good as Windows Explorer when I dialled down the K-Bling - but that was back when you could still install a small part of KDE without getting stuck with the whole damned ugly fat-filled lot of pseudo-dependencies).
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.
Although I cringe at the thought of Apple and its walled gardens, I hear you and I feel your pain. The Linux landscape seems more homogeneous and less 'choiceful' than it did even a few years ago. But at least give Xubuntu a try before you decide to give up on Linux altogether. And FWIW, I haven't experienced any crashes at all, (fingers crossed), and my installation is as up-to-date as automatic updates can make it.
'The Economy' is a giant Ponzi scheme whose most pitiable suckers are the youngest among us and the yet-unborn.
I've been a Linux user continuously through out that whole period, and I get what you're saying. For the last couple of years I've found Linux a lot less stable. Sometimes the culprit looks like the graphical environment/drivers, sometimes maybe not. But it's been really frustrating and I've not know where to begin hunting it down. Bug reports sure, but when your bug stays open for 18 months.....
There's an imbalance in development. Under windows, every hardware manufacturer does all they can to ensure their hardware is good - investing a lot of money in developing and testing the drivers. Under linux, the manufacturers usually don't care - aside from some server hardware, there just aren't enough resources to justify it from a business perspective. So development falls to three-man team on a side project, and sometimes it's down to community volunteers working from reverse-engineered specifications.
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.
Wait, I thought the honeybee problem was already found to be Pulseaudio's fault?
And hand Intel a monopoly? Careful there.
Table-ized A.I.
Systemd got my dog pregnant.
i've been using linux on the desktop for decades now. of the zillions of ui's available, i remember doing pretty well with either windowmaker, gome (2), xfce, never liked kde but there were always options. since the gome 3 fiasco i got into tiling window managers and realized i had never actually *needed* anything else.
so ymmv but for me particularly linux has the best desktop uis available today, period. ui is only complex if you want to get dumb peolple to do smart things, and that's just impossible, a chimera. windows and mac OS are a bloody testament to that, ffs.
As said by several others, BSODs are an error message from the kernel, which has died (detected that something is seriously wrong, and stopped itself before it overwrites the file system or something like that) - just like a "kernel panic" on Linux or OS X. And yes, they usually come from hardware problems (regardless of OS), sometimes from misconfiguration (again regardless of OS), and rarely from programming errors (regardless of OS).
What you're saying is that Microsoft code is trivial, since all non-trivial code has bugs, unhandled or poorly handled special cases etc.
ui is only complex if you want to get dumb peolple to do smart things
And this attitude is part of the whole problem - not that having to use professionally-designed operating system UI's is a problem of course, but it's not free. I do very smart things with my computers thank you very much, but wrestling with their configuration to make them actually work does not number amongst them.
Linux is fucking garbage.
Hey! That's my line!
EVERYTHING you can do in life boils down to a) taking actions b) saying words c) sleeping. There's nothing more that you, as a human, can do with your life.
Now, I'm not totally sure what point you were trying to make, and I certainly don't intend to discuss it with you any further, but a funny thing happens when you 'boil things down'; You lose what it was you were talking about in the first place. Boiled down to dust like that, nothing has any meaning, and discussion ceases to be possible or profitable for either party.