On Wed, Dec 21, 2016 at 07:54:11PM +0000, KY Srinivasan wrote: > > > > -----Original Message----- > > From: Stephen Hemminger [mailto:stephen@xxxxxxxxxxxxxxxxxx] > > Sent: Wednesday, December 21, 2016 10:03 AM > > To: Christoph Hellwig <hch@xxxxxxxxxxxxx> > > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>; Roman Kagan > > <rkagan@xxxxxxxxxxxxx>; Radim Krčmář <rkrcmar@xxxxxxxxxx>; KY > > Srinivasan <kys@xxxxxxxxxxxxx>; Vitaly Kuznetsov > > <vkuznets@xxxxxxxxxx>; kvm@xxxxxxxxxxxxxxx; Denis V . Lunev > > <den@xxxxxxxxxx>; Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>; > > x86@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Ingo Molnar > > <mingo@xxxxxxxxxx>; H. Peter Anvin <hpa@xxxxxxxxx>; > > devel@xxxxxxxxxxxxxxxxxxxxxx; Thomas Gleixner <tglx@xxxxxxxxxxxxx> > > Subject: Re: [PATCH 12/15] hyperv: move VMBus connection ids to uapi > > > > On Wed, 21 Dec 2016 09:58:36 -0800 > > Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > > > > On Wed, Dec 21, 2016 at 09:50:49AM -0800, Stephen Hemminger wrote: > > > > Lastly, there is licensing issues on headers. It would be good to have any > > > > userspace ABI headers licensed with a more liberal license so that BSD > > and DPDK drivers > > > > could use them directly. Right now each one reinvents. > > > > > > Microsoft could easily solves this problem by offering a suitably > > > liberally licensed header documenting the full HyperV guest protocol > > > that Linux and other projects could use. > > > > The issue is if same header file mixes kernel and userspace API stuff. > > > > Once the files are arranged right, I will submit trivial change to comments > > to indicate the liberal licensing of userspace API headers. > > Let us take this one step at a time. I know for a fact that not all the guest host > protocols on Hyper-V are guaranteed to be stable. Some of the protocols are part of > the published MSFT standards such RNDIS and these obviously are guaranteed to be > stable. For the rest it is less clear. The fact that we need to ensure compatibility of existing > Windows guests tells me that any host side changes will be versioned and the hosts will always > support older guests. > > I would like to minimize what we include in the uapi header; especially when MSFT has made no guarantees > with regards how they may be evolved. I will also work on getting some clarity on both stability and > under what license we would expose the uapi header. Am I correct assuming that QEMU is currently the only user of arch/x86/include/uapi/asm/hyperv.h? Then I think we're fine withdrawing it from uapi as a whole and letting QEMU pull it in through its header-harvesting scripts (as does now anyway). This would lift all licensing and longterm API stability expectations. Roman. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
