What does "make oldconfig" do exactly in the Linux kernel makefile?

linux makefile linux-kernel
fred basset picture fred basset · Nov 14, 2010 · Viewed 98.2k times · Source

Can anyone explain what the target "oldconfig" does exactly in the Linux kernel makefile? I see it referenced in some build documentation but never explained what it does exactly.

Answer

Ignacio Vazquez-Abrams picture Ignacio Vazquez-Abrams · Nov 14, 2010

It reads the existing .config file and prompts the user for options in the current kernel source that are not found in the file. This is useful when taking an existing configuration and moving it to a new kernel.

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