April 25, 2019

Linux 4.8 Debuts - But Maybe It Shouldn't Have

  • October 6, 2016
  • By Sean Michael Kerner

The Linux 4.8.0 kernel was officially release on October 2, becoming the fifth kernel release so far in 2016. The Linux 4.7 kernel was released on July 24.

As opposed to all the other kernel releases this year (and in fact in contrast to all kernel releases since 2.6) Torvalds really wasn't happy about this one, though the source of his displeasure didn't become apparent until after the release.

"So the last week was really quiet, which maybe means that I could probably just have skipped rc8 after all," Torvalds wrote in in his Linux 4.8 release announcement. "Oh well, no real harm done."

A day later on October 3, Torvalds addmits that he shouldn't have merged a late set of updates from kernel developer Andrew Morton.

"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)," Torvalds wrote.

The Morton patches involved the use of a BUG_on() line function that results in a termination of a running kernel. The patch was intended to help solve a bug that had originally landed in the Linux 3.15 kernel which was releasedon June 8, 2014.

"Yes, I'm grumpy. This went in very late in the release candidates, and I had higher expectations of things coming in through Andrew," Torvalds wrote. "Adding random BUG_ON()'s to code that clearly hasn't had sufficient testing is *not* acceptable, and it's definitely not acceptable to send that to me after rc8 unless it has gotten a *lot* of testing, which it clearly must not have had."

Rather than have BUG_ON(), Torvalds wants the patch changed to VM_WARN_ONCE().

"I've ranted against people using BUG_ON() for debugging in the past," Torvalds wrote. "Why the f*ck does this still happen? "

As it turns out, Torvalds first issueda warning about the use of BUG_ON() in October 2002.

Sean Michael Kerner is a senior editor at Linux Planet and InternetNews.com. Follow him on Twitter @TechJournalist

Most Popular LinuxPlanet Stories