Re: About the code style requirement

[Vladimir 'phcoder' Serbinenko]

On Fri, Oct 1, 2021 at 2:13 AM Qu Wenruo <wqu@suse.com> wrote:
>
>
>
> On 2021/9/30 18:51, Qu Wenruo wrote:
> >
> >
> > On 2021/9/30 18:20, Vladimir 'phcoder' Serbinenko wrote:
> >>
> >>
> >> Le jeu. 30 sept. 2021, 00:24, Qu Wenruo <wqu@suse.com
> >> <mailto:wqu@suse.com>> a écrit :
> >>
> >>
> >>
> >>     On 2021/9/29 23:38, Lennart Sorensen wrote:
> >>      > On Wed, Sep 29, 2021 at 03:04:59PM +0800, Qu Wenruo via
> >>     Grub-devel wrote:
> >>      >> Oh, didn't know there would be license problem.
> >>      >
> >>      > There often is. :)
> >>      >
> >>      >> Then it would be complex.
> >>      >>
> >>      >> Quite some code is directly copied from kernel without
> >>     modification, those
> >>      >> should still be GPL-2.0 only.
> >>      >>
> >>      >> For code already cross-ported to U-boot, it's GPL-2.0+, I guess
> >>     it would be
> >>      >> OK there.
> >>      >>
> >>      >> But from what I see in btrfs-progs, most of them is still GPL
> >> 2.0.
> >>      >>
> >>      >> I guess during the cross-port to U-boot, I have already broken
> >>     the GPL 2.0
> >>      >> requirement...
> >>      >>
> >>      >> Any advice on this problem?
> >>      >
> >>      > Does libbtrfsutils provide what you need?  It appears to be
> >>     LGPLv2.1+.
> >>      >
> >>
> >>     Unfortunately no.
> >>
> >>     BTW, U-boot is GPL v2.0+, would it be possible to cross port from
> >>     U-boot?
> >>
> >>     For the worst case I can craft a new interface from scratch, as GRUB
> >>     doesn't seem to need any write operation for the fs, thus quite some
> >>     code can be truncated and all transaction related functionality
> >> can be
> >>     removed.
> >>
> >> Sorry but this still doesn't cut it.
> >
> > Isn't GPLv2.0+ of U-boot compatible with the GPLv3.0+ of GRUB?
> >
> >> If you use the code, even if you adapt it, you need permission from
> >> original authors, either as a license or as a relicensing permission.
> >> I sometimes get asked for relicensing of the code I wrote and I often
> >> grant this request. Asking original authors may be worth it.
> >
> > In this U-boot case, the code is cross-ported from btrfs-progs by
> > myself, I can think of 3 or 4 other authors involved doing small bug
> > fixes in U-boot realm, thus asking for permission of U-boot code should
> > be pretty simple.
> >
> > But there are still code copied from kernel into U-boot, without
> > modification.
> >
> > Does it still prevent those kernel code from being used in GRUB?
> >
> >> Otherwise you're allowed to study the documentation and write code
> >> based from it. What you're allowed more than this depends on
> >> jurisdiction.
> >
> > Sure, in fact since GRUB doesn't require write support for the fs, I can
> > craft a different interface and start from scratch.
> >
> > But I still hope to get the license thing more clear, other than
> > starting a new (and less functional) btrfs code.
>
> After some chats with guys in SUSE, it's definitely a no-no to share any
> code from those projects.
>
> So I'll just start from scratch to craft a read-only btrfs
> implementation inside GRUB.

GRUB already has a btrfs implementation. Writing new one from scratch
instead of existing one is unwelcome. From scratch means new bugs.
Do you have problems with existing implementation? If so I prefer you
to fix the exact bugs rather than attempt to rewrite the entire thing
from scratch