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Linus Torvalds Says 'Buggy Crap' Made It Into Linux 4.8 (theregister.co.uk)
Two days after Linus Torvalds announced the release of Linux 4.8, he began apologizing for a bug fix gone bad. The Register reports: "I'm really sorry I applied that last series from Andrew just before doing the 4.8 release, because they cause problems, and now it is in 4.8 (and that buggy crap is marked for stable too)." The "crap" in question is an attempt to fix a bug that's been present in Linux since version 3.15. Torvalds rates the fix for that bug "clearly worse than the bug it tried to fix, since that original bug has never killed my machine!" Torvalds isn't happy with kernel contributor Andrew Morton, who he says is debugging with a known bad use of BUG_ON(). "I've ranted against people using BUG_ON() for debugging in the past. Why the f*ck does this still happen?" Torvalds writes, pointing to a 2002 post to the kernel mailing list outlining how to do BUG_ON() right. He later adds "so excuse me for being upset that people still do this shit almost 15 years later."
we're introducing systemgdb
So that I can live a lifetime where I never make a mistake and everyone in the world is a moron compared to me.
> I want to ... live a lifetime where everyone in the world is a moron compared to me.
You really don't. Dealing with morons is frustrating. When everyone is a moron (regarding the subject at hand), every interaction is frustrating.
I don't *excuse* Linus's temperament when it comes to kernel goofs, but I do understand it. There are a couple of very specific topics that I've studied and researched for decades. When I have discuss to those topics with people who have other specialties, and let them have input and make decisions that are within my realm of expertise but not theirs, it can be very frustrating. Because Linus is the expert on the Linux kernel, and he's a perfectionist, I understand it may get very frustrating to continually deal with mistakes that are, to him, stupid mistakes.
Linus isn't likely to invite you out for an ice cream cone to discuss a bug and your feelings about it but, he's right that it's a pretty bad bug (http://lkml.iu.edu/hypermail/linux/kernel/1610.0/00878.html). Luckily, the way kernel development works means that 99.9999% of users will never see this bug. No major distro has shipped this yet and by the time this kernel trickles down to users (if ever), the bug will be fixed.
As I'm not a developer, I had to read through some of the comments left to the original stories to figure out what the fuss was all about.
Maybe most Slashdot readers are more focused than I am on coding and already know all of this. But what I learned is that essentially, sticking this BUG_ON line someplace in the code causes Linux to do the equivalent of a Windows blue screen of death when it hits it. It's a purposeful way to cause an instant system halt because you believe the software should never reach that spot in the code, and if it does, you're worried that data corruption will result -- so better to halt things than let that happen.
It sounds like even back in 2002 though, Linus was expressing his dislike for using it and recommended a WARN_ON alternative that would just alert people to the issue but let things continue.
The thing is? I'm not entirely sure Linus's anger is warranted here? It sounds like basically, he's of the philosophy that "the code must go on". In other words, it's almost always better to keep the system running, despite any bugs, than to kernel panic and stop the whole thing. Perhaps in a world of virtual machines and servers running a whole slew of different processes at the same time, there's logic to this? (EG. If one of your boxes is needed to perform DNS, DHCP and/or other basic functions for a whole network -- you'd probably rather it keep doing those things, even if a bug is hit that means a process reading/writing data to files someplace else gets a critical error that could corrupt records in a database or improperly truncate some other file it was working with.)
BUT .... this could just as easily be subjective, based on where the bug lies and what it impacts, vs. what YOU consider a mission critical use of the machine in question. If BUG_ON saves data from loss, maybe that really is better for SOME users than letting it go on generating/logging warnings that people aren't going to notice right away?
I get the idea Linus leans the direction he does on this issue mainly because he wants any kernel he approves as "stable" to have that appearance, buggy or not.
Hmm, Andrew Morton is one of the two most trusted kernel developers, the other one being Al Viro. These two get absolutely no kiddie gloves from Linus when they do something they really, really, *really* ought to know better. OTOH, he pretty much merges anything these two send to him blindly on trust, *even when he is less than one week away from shipping it as a stable kernel*.
Does that make it a bit more clear?
And, believe me, these two get one or two rants like that at most once every 15 years. They are *that* good, and every single kernel developer worth something *knows* it. They get that level of rant with names included, because it is the other side of getting that level of trust out of Linus. Linus pretty much trusts Andrew Morton to be Linus himself.
And actually, so does everyone else [in the Linux kernel *upstream* community], as far as I know. So, yeah.
Buncha snowflakes and pop-tarts can't handle some feedback with a few 'fucks' thrown in??
You are in the wrong damn career. Computers and their software WAS BUILT with profanity. It is part of the culture.It is just like the military. Wars are won with profanity and murder.
If you don't want to hear it then go teach preschoolers how to color.
If you actually read the thread, that's basically where he says it's appropriate, and only then.
The problem appears to be that people are using that feature in situations where recovery is feasible and desirable, or they're using it under the assumption that it only impacts people running special development kernels.
Log in or piss off.
I do excuse it.
He is attacking the mistake of the person and not the person.
Taking such stuff personally is ridiculous, but I suppose it does give people something to talk about with something that's almost a non-issue.
Btw, I *am* the moron in kernel dev. My name is in the kernel changelog exactly once, which means I helped find and fix a problem when I had never done so before - I didn't know what the heck I was doing. Kernel development is very complex, with it's own set of rules quite different from userspace and I was in there trying to work on it, sending emails to the maintainer of the md subsystem (raid etc.) For anyone reading my emails or code, I was, compared to them, a moron. My flailing about might have been frustrating for them.
On the other hand, after almost 20 years I understand Linux pretty well from the userspace perspective, particularly the storage and security side of things. So when I'm in a meeting at work and the project manager wants to put certain files "on the C drive", when he wants to defrag and log in as Administrator, he becomes the moron and I'm the one getting frustrated.