Kexec command line length

[Vivek Goyal]

On Wed, Jan 30, 2008 at 03:59:47PM -0500, Neil Horman wrote:
> On Wed, Jan 30, 2008 at 03:53:23PM -0500, Vivek Goyal wrote:
> > On Tue, Jan 29, 2008 at 02:57:53PM -0500, Neil Horman wrote:
> > > 
> > > Ok, I've got a new patch here.  In response to Bernhard and Viveks concerns,
> > > I've added a few checks.  Bernhard, thank you for digging into the history of
> > > the addition of the 2048 byte command line.  As I understand what you've posted
> > > heres what we need to capture:
> > > 
> > > On X86:
> > > 	Boot loader version >= 2.06
> > > 		error if cmdline_len > setup_header.cmdline_size
> > > 	2.05 > Boot loader version > 2.06
> > > 		warn if cmdline_len > 255
> > > 	Boot loader version < 2.05
> > > 		error if cmdline_len > 255
> > > 
> > > on X86_64:
> > > 	Boot loader version >= 2.04
> > > 		error if cmdline_len > setup_header.cmdline_size
> > 
> > cmdline_size was introduced only in version 2.06. So this will run
> > into trouble on x86_64 version 2.04 and 2.05, isn't it?
> > 
> Then how did version 2.04 on x86_64 determine its maximum command line length?
> Or did it just assume a max length of 2048 bytes?

I think it just did not tell. There was no way for a kernel bzImage to
tell boot-loader what's the supported command line size is (Pre 2.06).

Thanks
Vivek