From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6368BC433F5 for ; Wed, 20 Oct 2021 17:35:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 47E4F6115B for ; Wed, 20 Oct 2021 17:35:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230387AbhJTRho (ORCPT ); Wed, 20 Oct 2021 13:37:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38314 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230134AbhJTRho (ORCPT ); Wed, 20 Oct 2021 13:37:44 -0400 Received: from mail-ot1-x329.google.com (mail-ot1-x329.google.com [IPv6:2607:f8b0:4864:20::329]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9D5CC061749 for ; Wed, 20 Oct 2021 10:35:29 -0700 (PDT) Received: by mail-ot1-x329.google.com with SMTP id g62-20020a9d2dc4000000b0054752cfbc59so7051294otb.1 for ; Wed, 20 Oct 2021 10:35:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=3qdkGS6nWGa6DIGxTkS5kzwbPgDeOBsvHVNSW721MxI=; b=48WLfHxpTQLpT0tUgWuSt4zXgmR64ij3Ikm8xUySS4voFZjXDqH/9AA3kqxblwubZa OLPsOO2SoGU+5CX+ksD6RkcZhFyMBejnYWIP/4t+clIqrnD/rWsK2UrsqcevALsA5yF4 Gjee61YE6DP7+kQG48wPdg0EDzZwNaDVIUQROJd2pCP2w5H2olWdul2nZAYLzd51dor2 xxlfFI4Kf9EJ/0HcBfZOZ9t4GcwolTJNgBDo2Xi1n2aE5UpzpJh7wnF/gkrQfvR41Hks 9QO+FqYnlm4ugw7sL37KMWtpORpTul7W+y1fk0J/9IGqgka1sAMLFCgk+NulkK2jOBdH Yawg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=3qdkGS6nWGa6DIGxTkS5kzwbPgDeOBsvHVNSW721MxI=; b=DwzB/Bu3ybhsQhox3yftlnL1z3MhtiuaYyTXbZUJyyH3dH6a/2Yb5MxxyVQ5Ag6j5N J86AOx3/THPxjtqlmNMOLwjkNDqteEyYsBByjx+nMnarj8y0eRiFP/l7yjY9Sxy8ocgr 5NVX9dpSTFuKQSRpP1ozTElDXTdIJP8kn1/Tz5jS/fVEMxgT6giJjPsSf4pOsWhDh0g/ PWrGhCbJ3/NkApMnDqEablTITTpeqNfxzl5Q2obxXtKJgdO2MqIHfMoo2BatqhukkMeG Zkm4q2NrUdwGrrx6Edwvn1wBq2kHwsE1KyFN2YjLKWCTe0U8smRTTDxEmEHCcaw/fqJ3 tGhQ== X-Gm-Message-State: AOAM5329ngVDjuWytIPjpmXewVX7Ek7zCifE6V5kKszlfa7Q4WYgCnH2 0/zjLKLwhpk+CRKSjZMq8l8e6w== X-Google-Smtp-Source: ABdhPJwZhE5aOVEBJg+B29uGYRLol/63NjjBsjTMQYekIxgCxYCQsJoWJUZ4yRJhVp+j2vsNKAx3MQ== X-Received: by 2002:a9d:424:: with SMTP id 33mr512439otc.340.1634751329074; Wed, 20 Oct 2021 10:35:29 -0700 (PDT) Received: from [192.168.1.30] ([207.135.234.126]) by smtp.gmail.com with ESMTPSA id ay42sm566290oib.22.2021.10.20.10.35.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 20 Oct 2021 10:35:28 -0700 (PDT) Subject: Re: [PATCH] fs: kill unused ret2 argument from iocb->ki_complete() To: Christoph Hellwig Cc: "linux-fsdevel@vger.kernel.org" , "linux-block@vger.kernel.org" , Greg Kroah-Hartman References: From: Jens Axboe Message-ID: Date: Wed, 20 Oct 2021 11:35:27 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 10/20/21 11:30 AM, Christoph Hellwig wrote: > On Wed, Oct 20, 2021 at 10:49:07AM -0600, Jens Axboe wrote: >> It's not used for anything, and we're wasting time passing in zeroes >> where we could just ignore it instead. Update all ki_complete users in >> the kernel to drop that last argument. >> >> The exception is the USB gadget code, which passes in non-zero. But >> since nobody every looks at ret2, it's still pointless. > > Yes, the USB gadget passes non-zero, and aio passes that on to > userspace. So this is an ABI change. Does it actually matter? > I don't know, but you could CC the relevant maintainers and list > to try to figure that out. True, guess it does go out to userspace. Greg, is anyone using it on the userspace side? -- Jens Axboe