The content of the .config file exported with tegra_defconfig does not match that of the tegra_defconfig file

[waf_803]

I executed the make ARCH=arm64 mrproper command in the Linux-for-Tregra/resources/kernel/kernel-5.10 directory, and then executed make ARCH=arm64 O=$HOME/kernel-output tegra_defconfig to export the . config file. However, I found that the exported .config file was inconsistent with the original content of tegra_defconfig, with a size of 33K and a content of 1392 lines; However, the generated .config file has 224.3K and 8551 lines.
Previously, I followed the instructions in https://docs.nvidia.com/jetson/archives/r35.4.1/DeveloperGuide/text/SD/Kernel/KernelCustomization.html and compiled the kernel and driver without making any modifications, successfully downloading them to the Jetson orin nano development board, and running them correctly.

Now I want to modify the kernel configuration through muenconfig to add or remove device drivers, but when I encounter the above problem, what should I do to obtain the correct original configuration?

Thank you very much

[DaveYYY]

You don’t need to care about this.
This is absolutely expected and not an issue/problem at all.

defconfig only saves config that is different from default ones specified in Kconfig, while .config contains every single config combined from both the defconfig file and all Kconfig.
That’s why there is a huge difference in file size.

[waf_803]

So, after modifying with meunconfig, I saved it in. config. The defconfig file has not changed. If I recompile it, my modifications will still be invalid?

Thank you very much

[DaveYYY]

savedefconfig is what you need.

[waf_803]

I understand. I can rename the newly saved .config to defconfig and overwrite the original defconfig, or modify the config_file in the nvbuild.sh file to the newly saved .config, right?

Thank you very much

[DaveYYY]

YES, exactly.