The 4.9 kernel has been released

Linus has released the 4.9 kernel, asexpected. Some of the headline features in 4.9 includeimproved security with virtually mapped kernelstacks,the memory-protection keys system calls,the BBR congestion-control algorithm,support for the Greybus bus architecture,shared extents in the XFS filesystem (which will be used to supportlightweight copy operations among other things),and much more.The code name has also been changed to "Roaring Lionus".In the end, 16,216 non-merge changesets were pulled for the 4.9 release,making this development cycle the busiest ever by far.