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Date:   Fri, 24 Nov 2023 03:12:23 +0100
From:   Petr Malat <oss@malat.biz>
To:     Masami Hiramatsu <mhiramat@kernel.org>
Cc:     paulmck@kernel.org, Randy Dunlap <rdunlap@infradead.org>,
        linux-kernel@vger.kernel.org, rostedt@goodmis.org
Subject: Re: [PATCH 2/2] bootconfig: Apply early options from embedded config
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Hi!
On Thu, Nov 23, 2023 at 11:18:05PM +0900, Masami Hiramatsu wrote:
> On Thu, 23 Nov 2023 11:04:00 +0100
> > On Thu, Nov 23, 2023 at 11:22:07AM +0900, Masami Hiramatsu wrote:
> > > BTW, we also need to make a block-list for some early params. some of those
> > > MUST be passed from the bootloader. E.g. initrd address and size will be
> > > passed from the bootloader via commandline. Thus such params in the embedded
> > > bootconfig should be filtered at the build time.
> > 
> > It's ok to configure these in the embedded bootconfig - in a case they are
> > provided by the bootloader, the bootconfig value is overridden, if not, the
> > value from bootconfig is used, so it works as expected.
> 
> I meant some params only bootloader knows, like where the initrd is loaded.
> Anyway, if user sets such value, it will break the kernel boot as expected :P.

If somebody sets these by hand, he probably knows what is he doing. I
remember myself hardcoding initrd size in Linux to workaround broken
bootloader.

I find it more important to warn the user when he tries to set early
options in initrd (assuming my change gets merged), as that's what
burned me.
  Petr