Linus Torvalds 已经在 Linux Kernel 邮件列表中宣布了 Linux Kernel 3.15：
So I ended up doing an rc8 because I was a bit worried about some last-minute dcache fixes, but it turns out that nobody seemed to even notice those. We did have other issues during the week, though, so it was just as well. The futex fixes and cleanups may stand out, but as usual there’s various other random fixes since rc8 in there too: mainly drivers (drm, networking, sound, usb etc), networking, scheduling and perf tooling.
But it’s all been fairly small and quiet, which *may* of course be due to the fact that last week was also the first week of the merge window for 3.16. That might have distracted some developers. I’m not entirely convinced I liked the overlap, but it seemed to work ok, and unless people scream really loudly (“Please don’t _ever_ do that again”) and give good reasons for doing so, I might end up doing that overlapping merge window in the future too if it ends up helping out with some particular timing issue.
That said, I also don’t think it was such a wonderful experience that I’d want to necessarily do the overlap every time, without a good specific reason for doing so. It was kind of nice being productive during the last week or rc (which is usually quite boring and dead), but I think it might be a distraction when people should be worrying about the stability of the rc.
Of course, maybe the overlap ends up meaning that we get less noise during the last week of stabilization, and it actually helps. It could go either way. I’d be interested to hear what people thought, although I _suspect_ most people don’t feel strongly either way.
Anyway, with 3.15 released, my “master” branch has already merged the work in my “next” branch on my local machine, and I’ll be decommissioning the “next” branch once I push that all out. After that, any future merge window work will happen on “master”, and we’ll be back to the normal single-branch model for my tree.
Linux Kernel 3.15 新特性：
EFI混合模式支持，64-bit 和 32-bit Linux kernel 支持 UEFI
更快的挂起和恢复时间
支持 Sony DualShock 4 控制器
新版 Linux kernel 可以让较新的笔记本电脑发挥更好的性能
对未来 CPU 前端 AVX-512 的 RDSEED 扩展的支持
对开源显卡驱动 NVIDIA Maxwell GPU 和 VCE 2.0 的支持及改进
视频编码支持 AMD 显卡
……
为Ubuntu安装和升级Linux Kernel 3.15
Ubuntu Kernel Team 发布的 DEB 包可以访问如下网址拿到：
http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.15-utopic/
安装的时候注意区分 64-bit 和 32-bit ，安装顺序如下：
linux-headers-3.15.0-xxxxxx_all.deb
linux-headers-3.15.0-xxx-generic / lowlatency-xxx_i386/amd64.deb
linux-image-3.15.0-xxx-generic / lowlatency-xxx_i386/amd64.deb
或者直接用如下命令把 Ubuntu 升级到 Linux Kernel 3.15 ：
32-bit Ubuntu
wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.15-utopic/linux-headers-3.15.0-031500-generic_3.15.0-031500.201406081435_i386.deb
wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.15-utopic/linux-headers-3.15.0-031500_3.15.0-031500.201406081435_all.deb
wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.15-utopic/linux-image-3.15.0-031500-generic_3.15.0-031500.201406081435_i386.deb
sudo dpkg -i linux-headers-3.15.0-*.deb linux-image-3.15.0-*.deb
64-bit Ubuntu
wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.15-utopic/linux-headers-3.15.0-031500-generic_3.15.0-031500.201406081435_amd64.deb
wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.15-utopic/linux-headers-3.15.0-031500_3.15.0-031500.201406081435_all.deb
wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.15-utopic/linux-image-3.15.0-031500-generic_3.15.0-031500.201406081435_amd64.deb
sudo dpkg -i linux-headers-3.15.0-*.deb linux-image-3.15.0-*.deb