From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-f70.google.com (mail-pl0-f70.google.com [209.85.160.70]) by kanga.kvack.org (Postfix) with ESMTP id 14DCB6B029B for ; Tue, 15 May 2018 09:51:02 -0400 (EDT) Received: by mail-pl0-f70.google.com with SMTP id a5-v6so106859plp.8 for ; Tue, 15 May 2018 06:51:02 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org. [2607:7c80:54:e::133]) by mx.google.com with ESMTPS id n10-v6si63101pgp.457.2018.05.15.06.51.00 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 15 May 2018 06:51:00 -0700 (PDT) Date: Tue, 15 May 2018 06:50:56 -0700 From: Matthew Wilcox Subject: Re: [PATCH] mm: Add new vma flag VM_LOCAL_CPU Message-ID: <20180515135056.GG31599@bombadil.infradead.org> References: <0efb5547-9250-6b6c-fe8e-cf4f44aaa5eb@netapp.com> <20180514191551.GA27939@bombadil.infradead.org> <7ec6fa37-8529-183d-d467-df3642bcbfd2@netapp.com> <20180515004137.GA5168@bombadil.infradead.org> <20180515111159.GA31599@bombadil.infradead.org> <6999e635-e804-99d0-12fc-c13ff3e9ca58@netapp.com> <20180515120355.GE31599@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Boaz Harrosh Cc: Jeff Moyer , Andrew Morton , "Kirill A. Shutemov" , linux-kernel , linux-fsdevel , "linux-mm@kvack.org" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Peter Zijlstra , Dave Hansen , Rik van Riel , Jan Kara , Matthew Wilcox , Amit Golander On Tue, May 15, 2018 at 04:29:22PM +0300, Boaz Harrosh wrote: > On 15/05/18 15:03, Matthew Wilcox wrote: > > You're getting dangerously close to admitting that the entire point > > of this exercise is so that you can link non-GPL NetApp code into the > > kernel in clear violation of the GPL. > > It is not that at all. What I'm trying to do is enable a zero-copy, > synchronous, low latency, low overhead. highly parallel - a new modern > interface with application servers. ... and fully buzzword compliant. > You yourself had such a project that could easily be served out-of-the-box > with zufs, of a device that wanted to sit in user-mode. For a very different reason. I think the source code to that project is publically available; the problem is that it's not written in C. > Sometimes it is very convenient and needed for Servers to sit in > user-mode. And this interface allows that. And it is not always > a licensing thing. Though yes licensing is also an issue sometimes. > It is the reality we are living in. > > But please indulge me I am curious how the point of signing /sbin/ > servers, made you think about GPL licensing issues? > > That said, is your point that as long as user-mode servers are sloooowwww > they are OK to be supported but if they are as fast as the kernel, > (as demonstrated a zufs based FS was faster then xfs-dax on same pmem) > Then it is a GPL violation? No. Read what Linus wrote: NOTE! This copyright does *not* cover user programs that use kernel services by normal system calls - this is merely considered normal use of the kernel, and does *not* fall under the heading of "derived work". What you're doing is far beyond that exception. You're developing in concert a userspace and kernel component, and claiming that the GPL does not apply to the userspace component. I'm not a lawyer, but you're on very thin ice.