Our layers can provide recipes for different versions of the same package. For example, the meta-fsl-arm layer contains several different types of Linux sources:
linux-imx: This corresponds to the Freescale BSP kernel image fetched from http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/linux-fslc: This is the mainline Linux kernel and fetched from https://github.com/Freescale/linux-fslclinux-timesys: This is a kernel with Vybrid platform support fetched from https://github.com/Timesys/linux-timesys
As we mentioned before, all recipes provide the package name (for example, linux-imx or linux-fslc) by default, but all Linux recipes must also provide the virtual/kernel virtual package. The build system will resolve virtual/kernel to the most appropriate Linux recipe name, taking into account the requirements of the build, such as the machine it is building for.
And within those recipes, linux-imx, for example, has both 2.6.35.3 and 3...