Kexec command line length

[Bernhard Walle]

* Vivek Goyal <vgoyal at redhat.com> [2008-01-29 16:41]:
> 
> I think 2048 command line support came much later. I think it came between
> version 2.05 and 2.06 (But somebody needs to dive into archive to verify).
> Because command line size could go beyond 256, we introduced cmdline_size
> parameter in version 2.06 to let a boot loader know.

Large command line support was added with

    cca97de1184f6000d22b4106d47687b31cca1fa3
    v2.6.20-1929-gcca97de

which means that it was merged 2.6.21.

> What Bernanrd seems to be talking about a small window where boot protocol
> was 2.05 but supported command line size was still 2048.

2.05 was added with

    be274eeaf20b4c7155242645d5e2c48b023e609b
    v2.6.19-1394-gbe274ee

which means that it was merged 2.6.20. But it got implemented for i386
only that time, so x86_64 still had the 2.04 version.

The command line length in the boot protocol was added with

    8f9aeca7a081d81c4c9862be1e04f15b5ab5461f
    v2.6.21-1864-g8f9aeca

which menas that it was merged 2.6.22.

> if (protocol version > 2.06)
> 	error user depending on cmdline_size;
> else if (protocol version > 2.05 && protocol version < 2.06)
> 	warn on cmdline being more than 256. We don't know for sure.
> else
> 	error out if cmdline is greater than 256

The problem is 2.6.21: It had on x86_64 2.04 boot protocol but
2048 command line size. I just verified this via the tarball. :(

Maybe it could be implemented with versions ...


        Bernhard