On Mon, Mar 31, 2025 at 08:29:21AM +0000, 谢致邦 (XIE Zhibang) wrote:

quoted

Later arguments override earlier arguments. Any compiled-in command line
needs to be overridable by user supplied input from the boot loader. The
current behaviour is correct.

CMDLINE_EXTEND is for the built-in command line to "Extend bootloader kernel
arguments", not for the bootloader command line to extend/override built-in
command line.

Don't forget that the default empty CMDLINE already gives the bootloader the
ability to override everything. Not to mention that even if CMDLINE is not
empty, the default CMDLINE_FROM_BOOTLOADER continues to give the bootloader the
ability to override all.

The help text:

+         The command-line arguments provided by the boot loader will be
+         appended to the default kernel command string.

so, you end up with default kernel command string _followed by_ the
boot loader arguments. This allows the boot loader arguments to
override anything that is in the default kernel command string.
That's why it is a _default_ - it can be overrided.

If the boot loader command string is extended by the default kernel
command string, then that doesn't happen.

CMDLINE_EXTEND is default _followed by_ boot loader.

You're wanting it to be the other way around. That's broken.

No.

Sorry.

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