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. So 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.
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.
Anyway, there's certainly been other things going on too, but the VM
regression was the one that kept me personally busy, and held up the
release.
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. The appended shortlog is
about as good an overview as anything.
Linus
---