Linux: 2.6.34-rc4, "Hunting A Really Annoying VM Regression"

Jeremy — Tue, 13 Apr 2010 05:16:30 +0000

"It's been two weeks rather than the usual one, because we've been hunting a really annoying VM regression that not a lot of people seem to have seen, but I didn't want to release an -rc4 with it," began Linux creator Linus Torvalds, announcing the 2.6.34-rc4 Linux kernel. He explained, "we had the choice of either reverting all the anon-vma scalability improvements, or finding out exactly what caused the regression and fixing it. And we got pretty close to the point where I was going to just revert it all." Linus continued:

"Absolutely _huge_ kudos to Borislav Petkov who reported the problem and was able to not just reliably reproduce it, but also test new patches to try to narrow things down at a moments notice. The thing took ten days of emails flying back and forth, and Borislav was there all the time, day and night, through several patches that tried to fix it (several real bugs, but not the one he hit) and lots of patches to just add instrumentation to get us nearer to the cause of the problem. And finally, today, confirmation that we actually nailed the problem. So if anybody has been seeing a oops (or sometimes a GP fault) in page_referenced(), that should be gone now."

As for the rest of the changes, Linus noted, "the bulk of the changes come from drivers - a new network driver (cxgb4), but also updates to the radeon and nouveau drivers. And then there is the random updates everywhere." Read on for the full changelog.

Linux: Regressions In 2.6.22-git

Jeremy — Thu, 19 Jul 2007 17:49:51 +0000

Michal Piotrowski sent out an updated list of known regressions in the 2.6.22-git kernel.

Linux: Tracking Regressions

Jeremy — Mon, 21 May 2007 10:33:05 +0000

The task of tracking regressions between kernel releases [story] has been picked up by Michal Piotrowski who maintains a "known regressions" wiki page at Kernel Newbies. The list is divided into sections and mailed out to the lkml after each release candidate.

KernelTrap - regressions

Linux: 2.6.34-rc4, "Hunting A Really Annoying VM Regression"

Linux: Regressions In 2.6.22-git

Linux: Tracking Regressions