Linus Torvalds: Buggy kernel-killing crap made it into Linux 4.8

Linux founder Linus Torvalds just gave developers a public scolding as he admitted that some "buggy crap" made it into the "stable" 4.8 release of the Linux kernel.

The Inquirer reports the crap in question is a patch for a bug that's been present in Linux since version 3.15. Unfortunately, it appears the cure is worse than the disease because the fix can kill the kernel. Here's what Torvalds wrote on the Linux Kernel Mailing list:

“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!”

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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.”

Additionally, Torvalds said it's probably time to remove BUG_ON() once and for all:

I should have reacted to the damn added BUG_ON() lines. I suspect I will have to finally just remove the idiotic BUG_ON() concept once and for all, because there is NO F*CKING EXCUSE to knowingly kill the kernel.