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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57432C433EF for ; Wed, 29 Jun 2022 09:29:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232838AbiF2J3J (ORCPT ); Wed, 29 Jun 2022 05:29:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231860AbiF2J3H (ORCPT ); Wed, 29 Jun 2022 05:29:07 -0400 Received: from mail-ed1-x529.google.com (mail-ed1-x529.google.com [IPv6:2a00:1450:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D4C2539158 for ; Wed, 29 Jun 2022 02:29:06 -0700 (PDT) Received: by mail-ed1-x529.google.com with SMTP id z19so21291581edb.11 for ; Wed, 29 Jun 2022 02:29:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=l/qP5VS2/NgqMqeMrxhq05tHUxUfi9oaN9njnjyipZ0=; b=3nK/vgsJG7pSe56dwjn6/TTj+WrWPKlRifa6aHQCoF0IuiKiAOXDKGXwGqCg69M28T L983TR0sKAD/klCuNBZOPjN6DyLdzukM5BFpinp/HrDtpz7WqbNPzQjSN8WUmljnuHTH RByar0huFgSJ7wVUiST9KLw9blBtOlsi3o0rX75DUz30EWhyOw2E9tuf9jGzycPLsVQK Pt/OuuaS0NA/+g3H6wrUscacs2qYNrKuu+QLNI8VfjpAeV0EFdYx44fFrgcXsDbfV9xn 4mwnio63SId/q5sOtVm9uuDzwNuI84bbw2RNs1TWWbw2SbpD0bVB3Ca0ydqDqOUILPVs DG8w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=l/qP5VS2/NgqMqeMrxhq05tHUxUfi9oaN9njnjyipZ0=; b=KfBREUUJPxj0dXeiac0ebZj9eOFlVUc+qWUolC8xtrOU9k57gzGvzHGWYalFGcg6+G PuFCNOIeAaAz9WzBqS0HOCPCTjZSe0jOROkmslG7yD2cjzs/flrqPy1zMdz3vIdellgt m9UEfG44nKV6k9kcRie5hifeNnjrgItSiXZG5qFF/OrzRAc6ftuZ0aR9Sd9XmF2vNLA2 59eKuAXK/UD0R4Mc8A7iEbbH6zwj0BeBMHQhCw+MkhFXBMdHWy4GIMSo8qDgMKfVtpZc AhSqe4W8te5p3CBey6AsE3Y8um4Tnbi5vjpkup0P50nILBN72AVIPPT4Cvb29heY4c0m o5pg== X-Gm-Message-State: AJIora9uw3Y2Sc9z2fHsL5OM92azut3kNjmByPfxQC24Nhky8V1Chw+3 igLXEdV3ZWqnC3ceRmyj/TIlQi3fPpk8vY8RxGYK X-Google-Smtp-Source: AGRyM1sS12JVNqIJoizAX444CBbg5tqjy6FdigCkOcz+AdW5ySG8VJO0ejggmCP2QgNUtnTubpIHHfUwscO889cS7Gg= X-Received: by 2002:a05:6402:d6b:b0:435:7170:cf15 with SMTP id ec43-20020a0564020d6b00b004357170cf15mr2877724edb.314.1656494945421; Wed, 29 Jun 2022 02:29:05 -0700 (PDT) MIME-Version: 1.0 References: <20220629082541.118-1-xieyongji@bytedance.com> <20220629082541.118-7-xieyongji@bytedance.com> <20220629042856-mutt-send-email-mst@kernel.org> <20220629052130-mutt-send-email-mst@kernel.org> In-Reply-To: <20220629052130-mutt-send-email-mst@kernel.org> From: Yongji Xie Date: Wed, 29 Jun 2022 17:28:55 +0800 Message-ID: Subject: Re: [PATCH 6/6] vduse: Update api version to 1 To: "Michael S. Tsirkin" Cc: Jason Wang , Liu Xiaodong , Maxime Coquelin , Stefan Hajnoczi , virtualization , linux-kernel Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 29, 2022 at 5:22 PM Michael S. Tsirkin wrote: > > On Wed, Jun 29, 2022 at 05:02:40PM +0800, Yongji Xie wrote: > > On Wed, Jun 29, 2022 at 4:33 PM Michael S. Tsirkin wrote: > > > > > > On Wed, Jun 29, 2022 at 04:25:41PM +0800, Xie Yongji wrote: > > > > Let's update api version to 1 since we introduced > > > > some new ioctls to support registering userspace > > > > memory for IOTLB. > > > > > > > > Signed-off-by: Xie Yongji > > > > > > > > > Adding new ioctls does not justify things like this. > > > > > > > What I want to do here is make userspace know whether this feature is > > supported or not in the kernel. So do you think we need to add > > something like CHECK_EXTENSION ioctl here? > > Why bother? unsupported ioctls just return an error code. > Oh, yes. I forgot the error code of the ioctls. Thanks, Yongji