From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dominique Martinet Subject: Re: BUG: corrupted list in p9_read_work Date: Wed, 10 Oct 2018 16:40:59 +0200 Message-ID: <20181010144059.GA20918@nautica> References: <000000000000ca61cd0571178677@google.com> <000000000000fddb150577c15af6@google.com> <20181009020949.GA29622@nautica> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Leon Romanovsky , syzbot , David Miller , Eric Van Hensbergen , LKML , Latchesar Ionkov , netdev , Ron Minnich , syzkaller-bugs , v9fs-developer@lists.sourceforge.net To: Dmitry Vyukov Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Dmitry Vyukov wrote on Wed, Oct 10, 2018: > How can they be faked? > If we could create a private rdma/virtio stub instance per test > process, then we could I think easily use that instance for 9p. But is > it possible? "RDMA" itself can be faked pretty easily nowadays, there's a "rxe" driver that is soft RDMA over ethernet and can run over anything. The problem is that you can't just give the client a file like trans fd; you'd need to open an ""rdma socket"" (simplifying wording a bit), and afaik there is no standard tool for it ; or rather, the problem is that RDMA is packet based so even if there were you can't just write stuff in a fd and hope it'll work, so you need a server. If you're interested, 9p is trivial enough that I could provide you with a trivial server that works like your file (just need to reimplement something that parses header to packetize it properly; so you could write to its stdin for example) ; that'd require some setup in the VM (configure rxe and install that tool), but it would definitely be possible. What do you think ? For virtio, I'm not as familiar with the environment so I do not know if there are ways to fake it as easily unfortunately. > Testing on real hardware is mostly outside of our priorities at the > moment. I mean syzkaller itself can be run on anything, and one could > extend descriptions to use a known rdma interface and run on a real > hardware. But we can't afford this at the moment. Sure, I understand that. > As far as I understand RDMA maintainers run syzkaller on real > hardware, but I don't know if they are up to including 9p into > testing. +Leon I'd be interested in knowing what kind of tests runs there :) -- Dominique Martinet