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 70E9BC4332F for ; Wed, 29 Sep 2021 16:14:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E14061353 for ; Wed, 29 Sep 2021 16:14:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345526AbhI2QQV (ORCPT ); Wed, 29 Sep 2021 12:16:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40266 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345129AbhI2QQQ (ORCPT ); Wed, 29 Sep 2021 12:16:16 -0400 Received: from mail-qt1-x832.google.com (mail-qt1-x832.google.com [IPv6:2607:f8b0:4864:20::832]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4397BC061764 for ; Wed, 29 Sep 2021 09:14:35 -0700 (PDT) Received: by mail-qt1-x832.google.com with SMTP id t2so2799033qtx.8 for ; Wed, 29 Sep 2021 09:14:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=2/DOweLZi1LYkI2NBZkoCxBZv2x+eGa4aLJUobv2L1o=; b=PboCFsQCjD2723LhLYT/hgjkJdWoO/Qr7CahpEILXMofMHRSJifpiRAfKU1XinqG67 AhaKbB8c6M8JSRC5xiTi7/mAm/tA9MPNU7KxHCJwsT3TcNZEvni9gIYQHpEE2twn3Lb1 XEQAd+awFGQvrjYTvZmCM8JGYWsNB3RPHyweKekQKlu0doslil+cuRJjDW4QCgq+lEPM +n+cIMyeEp1R/IhkNJfh1Av4WkSJThIfSSnZIbzDvJEu3PUwI3+Rbi/hzxYhv46mrVo4 C2Ww+6AXHWKS7AbB4UjQ/vimBLFOVmr7X6zBKKsORWg5TkRoxZSArV+Enk/yQJYpQidO Yk+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=2/DOweLZi1LYkI2NBZkoCxBZv2x+eGa4aLJUobv2L1o=; b=obyz7Jw75wezq+87xAjLcBQBM32QVA/RC+rqopeWl8bFEuwDj8FuMlyGQUhn4nS2CY zXU4wNN4Hb0YvyRGjmlFwCXAd+ZIR7IfRxDpIjJVMbExq2+FIi7gRG5hvW1ZcujQeKW2 DuSOZFb835BrQGcKE36kaAz/4LbQz8g47Z0OdPx50L8Ffx7/uYq/AvgNw/kYY68YUzWy npa+PT5PDK4QADv5SfoId3pjHlRy/BwiDcJMZpumZSfuzaoyjvit62kZpihUPPuzFGXm CpD8J760dmhDRQ0ILWjByxa3o+gtuBOOjj3jKUgjjBzB1Y5gvzKaMXIGjdohnShS7jgd hmHA== X-Gm-Message-State: AOAM5307hMIwBmX3mbAKxDqDbO+0Jzc/p/LsvjQ89A9FloFpUb6ssing VhwiKYclpw4LlWnTUHDiaJ1fPw== X-Google-Smtp-Source: ABdhPJz3genm3m/pxNLME0A8yc2mxcvVNovagYhEOWLyS+VtXcmuaVaqUzXPZnkRrIL56CYjTIjNqA== X-Received: by 2002:ac8:610f:: with SMTP id a15mr758684qtm.387.1632932074489; Wed, 29 Sep 2021 09:14:34 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-142-162-113-129.dhcp-dynamic.fibreop.ns.bellaliant.net. [142.162.113.129]) by smtp.gmail.com with ESMTPSA id v17sm163354qkp.75.2021.09.29.09.14.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Sep 2021 09:14:33 -0700 (PDT) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1mVcE5-007cDu-62; Wed, 29 Sep 2021 13:14:33 -0300 Date: Wed, 29 Sep 2021 13:14:33 -0300 From: Jason Gunthorpe To: Max Gurtovoy Cc: Alex Williamson , Leon Romanovsky , Doug Ledford , Yishai Hadas , Bjorn Helgaas , "David S. Miller" , Jakub Kicinski , Kirti Wankhede , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-rdma@vger.kernel.org, netdev@vger.kernel.org, Saeed Mahameed , Cornelia Huck Subject: Re: [PATCH mlx5-next 2/7] vfio: Add an API to check migration state transition validity Message-ID: <20210929161433.GA1808627@ziepe.ca> References: <20210927164648.1e2d49ac.alex.williamson@redhat.com> <20210927231239.GE3544071@ziepe.ca> <25c97be6-eb4a-fdc8-3ac1-5628073f0214@nvidia.com> <20210929063551.47590fbb.alex.williamson@redhat.com> <1eba059c-4743-4675-9f72-1a26b8f3c0f6@nvidia.com> <20210929075019.48d07deb.alex.williamson@redhat.com> <20210929091712.6390141c.alex.williamson@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Sep 29, 2021 at 06:28:44PM +0300, Max Gurtovoy wrote: > > So you have a device that's actively modifying its internal state, > > performing I/O, including DMA (thereby dirtying VM memory), all while > > in the _STOP state? And you don't see this as a problem? > > I don't see how is it different from vfio-pci situation. vfio-pci provides no way to observe the migration state. It isn't "000b" > Maybe we need to rename STOP state. We can call it READY or LIVE or > NON_MIGRATION_STATE. It was a poor choice to use 000b as stop, but it doesn't really matter. The mlx5 driver should just pre-init this readable to running. Jason