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Date:   Sat, 26 Mar 2022 09:54:20 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     Masahiro Yamada <masahiroy@kernel.org>,
        Padmanabha Srinivasaiah <treasure4paddy@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
        "open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
        Randy Dunlap <rdunlap@infradead.org>
Subject: Re: [PATCH v2 2/3] bootconfig: Support embedding a bootconfig file
 in kernel
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On Sat, 26 Mar 2022 21:40:40 +0900
Masami Hiramatsu <mhiramat@kernel.org> wrote:

> > BTW, it is already possible to embed kernel parameters
> > into the kernel.
> > Is this another implementation of CONFIG_CMDLINE?

If one changes CONFIG_CMDLINE, does it require a rebuild of vmlinux?

> 
> Yes, it is the bootconfig version of the CONFIG_CMDLINE.
> Since some boot-time tracing feature depends on the bootconfig (those can
> not be set via kernel cmdline), we need this feature for those features
> on non-initrd boot system.

Yes, the kernel command line has a fixed size, and with tracing
options, we can easily go over it.

bootconfig is a way to have an unlimited size and also be able to have
a better and more reasonable formatting to express options for things
like tracing.

-- Steve