Linux 4.9 is coming along nicely, with Linus Torvalds emitting the fourth release candidate on Saturday evening.
But before he got there, he offered a minor kernel mailing list explosion when developer Miklos Szeredi proposed “the concept of feature flags to allow backward incompatible changes to the overlay format” in overlayfs. Szeredi opined that the feature was long overdue.
Torvalds disagreed that the feature was needed, never mind overdue. Another poster to the Linux Kernel Mailing List, Amir Goldstein, asked for clarification of Linus' thinking.
Torvalds responded that the proposed code came at the wrong time, said “the whole concept seems frankly totally misdesigned” and then offered this observation:
There's no f*cking explanation of why we'd even want this crap. Not in the commit message, not in the pull request, not *anywhere*.
Which is stern stuff, but also pretty mild compared to previous Torvalds F-bombs that offered rather more personal criticisms.
Changes to overlayfs therefore won't be making it into this Linux release.
But plenty more will: Torvalds post says he slipped out rc4 on Saturday evening because he didn't want it to get any bigger. The bulk of the new bits impact “network drivers and core networking” but there's also “architecture updates (sparc and mips stand out, but there's some x86 and parisc too, and some tiny arm updates).”
Torvalds also hopes that a series of uninitialised variable warning fixes continue to appear in time for their appearance in Linux 4.9.
He expects seven release candidates ought to do it this time around, which would make for early December release. ®