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Date:   Tue, 17 Oct 2023 16:10:42 +0530
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References: <20230417162415.GF1391488@zorba>
Subject: Re: [PATCH 1/4] add generic builtin command line
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From:   Pratyush Brahma <quic_pbrahma@quicinc.com>
In-Reply-To: <20230417162415.GF1391488@zorba>
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Hi Daniel

We have a usecase which requires this patch necessarily. For android 
usecases, we have two different build variants
differentiated by defconfigs - production and debug. However, we only 
have a single dts for both these variants.


We want to enable certain features like page owner and slub debug which 
require cmdline params in addition to
their respective configs to be enabled. Enabling page_owner and 
slub_debug options in dts file enables it for both
production and debug variants. These features have significant memory 
overhead which are undesirable for
our production environment. However, these are necessary for debug 
environment to enable internal testing and debug.
Currently, android uses out-of-tree configs like CONFIG_CMDLINE_EXTEND 
to do so in gki_defconfig [1].
One option is to use CMDLINE_FORCE option which would enable these 
cmdline params but this disables the bootloader to add
any additional cmdline params which may be necessary.


For such a usecase, the CONFIG_CMDLINE_PREPEND seems to be quite useful 
as it would help to stitch bootloader
and the desired build variant's configs together. Can you please help to 
merge this patch?


[1] 
https://android.googlesource.com/kernel/common/+/refs/heads/android14-6.1-lts/arch/arm64/configs/gki_defconfig#62