I recently managed to find time to clean up and submit my patches for xz kernel compression support on ARM, which I started working on back in November, during my flight to Linaro Connect. However, it was too late as Russell King, the ARM Linux maintainer, already accepted a similar patch, about 3 weeks before my submission. The lesson I learned was that checking a git tree is not always sufficient. I should have checked the mailing list archives too.
The good news is that xz kernel compression support should be available in Linux 3.4 in a few months from now. xz is a compression format based on the LZMA2 compression algorithm. It can be considered as the successor of lzma, and achieves even better compression ratios!
Before submitting my patches, I ran a few benchmarks on my own implementation. As the decompressing code is the same, the results should be the same as if I had used the patches that are going upstream.