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[209.85.220.41]) by mx.google.com with SMTPS id f54sor14624960qvf.35.2019.03.24.11.49.03 for (Google Transport Security); Sun, 24 Mar 2019 11:49:04 -0700 (PDT) Received-SPF: pass (google.com: domain of joelaf@google.com designates 209.85.220.41 as permitted sender) client-ip=209.85.220.41; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=Kpr2Pj89; spf=pass (google.com: domain of joelaf@google.com designates 209.85.220.41 as permitted sender) smtp.mailfrom=joelaf@google.com; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=3E5PbD/R8KE0AK8IEXA0HiRaTNZrWClh6JLvVEMcjJA=; b=Kpr2Pj89AACdsy9YXGxjPNM2856WloQP5gTnJGcMPHcDulRXB24JL1Q+55SZ8atsZ5 pTu+lL+XbvMqTKShWIDc2U1PeoFD/B0fTrhrmRmWHQL39Y2XUuH3WcWHArJ1fChakr8M +EQugGx8TeJA6+qHQWTme3C9lUj/6RhHLE8pKqo9CAO9rB/MTEFgfWe9ZuB4k7PmnI/k 7aJ3xsiegOQE/AqwkFIiHUTDJZZPTG8tjvyTShIZRB/ft+NCDYcNMITqGZilJqRKZHGJ kx++06XqoMPr0nh41EIxB69l6ghrb5N80kv2wK9f8K2619cn8tz2Rpgp8rzE15hkiie1 mkSg== X-Google-Smtp-Source: APXvYqwCwbatcl/nUNjqKbqJbunhhvR2uPQnvJ0q0OU9X7yHkG1uyIFEAYpQ+V9uE6Rkswj54NQTVvUhOderhX900JE= X-Received: by 2002:a0c:d2fa:: with SMTP id x55mr17704481qvh.161.1553453343410; Sun, 24 Mar 2019 11:49:03 -0700 (PDT) MIME-Version: 1.0 References: <20190319231020.tdcttojlbmx57gke@brauner.io> <20190320015249.GC129907@google.com> <20190320035953.mnhax3vd47ya4zzm@brauner.io> <4A06C5BB-9171-4E70-BE31-9574B4083A9F@joelfernandes.org> <20190320182649.spryp5uaeiaxijum@brauner.io> <20190320185156.7bq775vvtsxqlzfn@brauner.io> <20190324144404.GA32603@mail.hallyn.com> In-Reply-To: <20190324144404.GA32603@mail.hallyn.com> From: Joel Fernandes Date: Sun, 24 Mar 2019 14:48:51 -0400 Message-ID: Subject: Re: pidfd design To: "Serge E. Hallyn" Cc: Daniel Colascione , Christian Brauner , Joel Fernandes , Suren Baghdasaryan , Steven Rostedt , Sultan Alsawaf , Tim Murray , Michal Hocko , Greg Kroah-Hartman , =?UTF-8?B?QXJ2ZSBIasO4bm5ldsOlZw==?= , Todd Kjos , Martijn Coenen , Ingo Molnar , Peter Zijlstra , LKML , "open list:ANDROID DRIVERS" , linux-mm , kernel-team , Oleg Nesterov , Andy Lutomirski , Kees Cook Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, Mar 24, 2019 at 10:44 AM Serge E. Hallyn wrote: > > On Wed, Mar 20, 2019 at 12:29:31PM -0700, Daniel Colascione wrote: > > On Wed, Mar 20, 2019 at 11:52 AM Christian Brauner wrote: > > > I really want to see Joel's pidfd_wait() patchset and have more people > > > review the actual code. > > > > Sure. But it's also unpleasant to have people write code and then have > > to throw it away due to guessing incorrectly about unclear > > requirements. > > No, it is not. It is not unpleasant. And it is useful. It is the best way to > identify and resolve those incorrect guesses and unclear requirements. No problem, a bit of discussion helped set the direction. Personally it did help clarify lot of things for me. We are hard at work with come up with an implementation and are looking at posting something soon. I agree that the best is to discuss on actual code where possible.