linux-kernel - Re: [PATCH 2/2] Honor 'quiet' command line option in real mode boot decompressor.

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Message-Id: <1212099906.5422.0.camel@gaara.bos.redhat.com>
Date:	Thu, 29 May 2008 18:25:06 -0400
From:	Kristian Høgsberg <krh@...hat.com>
To:	"H. Peter Anvin" <hpa@...or.com>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] Honor 'quiet' command line option in real
	mode	boot decompressor.

On Thu, 2008-05-29 at 13:30 -0700, H. Peter Anvin wrote:
> Kristian Høgsberg wrote:
> >> You know... we already have a command-line parser in the real-mode part 
> >> of the boot code, and it already extracts the "quiet" option: we should 
> >> be able to do this by passing a bit in "loadflags" (bit 5 suggested.)
> > 
> > Hmm, as far as I understand the boot code, the decompressor consists of
> > just head_32/64.S and misc.c plus the #included inflate.c and the
> > compressed image in piggy.o.  In this environment there is no command
> > line parser, it's only available once the image has been decompressed.
> 
> > Or are you suggesting parsing the "quiet" option in the bootloader and
> > then setting the loadflags bit from there?  That's certainly doable, and
> > I can update grub accordingly, but just parsing the command line seems
> > like a simple, more local fix.  I don't have a strong preference,
> > though.
> 
> I think you're missing something: the decompressor is the *second stage* 
> of the boot code; the first stage is the real-mode code (arch/x86/boot). 
>   I'm suggesting passing the flag from the real-mode code to the 
> decompressor, not from the boot loader (in the common case.)

Indeed, I had it the wrong way around.  I like the bootflag approach,
updated patches coming up.

thanks,
Kristian


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