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 X-Spam-Level: X-Spam-Status: No, score=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E7F1C433DF for ; Thu, 11 Jun 2020 00:07:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 34AA920691 for ; Thu, 11 Jun 2020 00:07:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="AK60Uv+5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726928AbgFKAHK (ORCPT ); Wed, 10 Jun 2020 20:07:10 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:51273 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726820AbgFKAHK (ORCPT ); Wed, 10 Jun 2020 20:07:10 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591834028; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bG1f0DEkS8GNLNtqNZirTqogQo8gFsAlps/puTKPgPA=; b=AK60Uv+5qz8XB8721z0baPURuQmaafU/aQyaInK+IONIgQPc67OApzMeaXPIdgAUn+GuDK SbG76QzPuj5wzcXIALfP8V33WJl5whbw/cqtsqdQzQXqkWHn5ATUzTkufgFrvelzqFejoB xlhfMrsworK36QaRqXnS/1fNtKEIDu4= Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-415-yc06NXITOjGXp2g7QjSikQ-1; Wed, 10 Jun 2020 20:07:07 -0400 X-MC-Unique: yc06NXITOjGXp2g7QjSikQ-1 Received: by mail-wr1-f72.google.com with SMTP id e1so1784790wrm.3 for ; Wed, 10 Jun 2020 17:07:07 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; 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=bG1f0DEkS8GNLNtqNZirTqogQo8gFsAlps/puTKPgPA=; b=pQuyMwvQeg1zYVQVLCcBjh6FjwroM1BPQYlOAhisBwvOzFwazThmIQt5ne2gNNa6jD oDy/a6FjGmd/qDqV/U8IbdJcgjG3rbczo8dPh5bh9qFUEWe0otl4dqZ0xSIzEDlSd2Qu v/ybuhpdYkej7QVk6QZ7rN4datqfGAFiy9jeSJJuRHbXMXa1wsjpQE9RWur047eQdJKS b84uzzpyGtTuUu3bcnqzjtMZ5bRAOvnrC8/lKEU9p0Lkxq/wdNhleNKuRtK/wqgEQW0q 16btHOp8QoyATtYScmeTdXPL5d2vinZ3ACVCMHxDSuW3qiOv4YRs97jM0kHvOhz0GdPz vbQw== X-Gm-Message-State: AOAM530tyzMvyvvgQrdRDPPexihErobJx/3AO1K0qSbc2u3Y4SxvjMvZ +1csPkH5E+NWf/rqBDbTWhj3WYYxfiLhBDuTUxi4I0U2DwZYPB1Ah7xjIiqgX2H3qB3KGGnB8X5 W3h0p/HrQuT3WYxO64h1hdxjd X-Received: by 2002:a1c:1d94:: with SMTP id d142mr5500424wmd.42.1591834026141; Wed, 10 Jun 2020 17:07:06 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyERZxGXMtunnFSc+m5agcYq7aVk8aBfHzDqaphsJnY9S7fHd1kWpGwVRoNb/LyjwtNx/2Xvg== X-Received: by 2002:a1c:1d94:: with SMTP id d142mr5500407wmd.42.1591834025935; Wed, 10 Jun 2020 17:07:05 -0700 (PDT) Received: from ?IPv6:2001:b07:6468:f312:29ed:810e:962c:aa0d? ([2001:b07:6468:f312:29ed:810e:962c:aa0d]) by smtp.gmail.com with ESMTPSA id v28sm2194252wra.77.2020.06.10.17.07.04 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 10 Jun 2020 17:07:05 -0700 (PDT) Subject: Re: [PATCH 1/2] KVM: async_pf: Cleanup kvm_setup_async_pf() To: Sean Christopherson , Vitaly Kuznetsov Cc: kvm@vger.kernel.org, Wanpeng Li , Jim Mattson , Vivek Goyal , linux-kernel@vger.kernel.org References: <20200610175532.779793-1-vkuznets@redhat.com> <20200610181453.GC18790@linux.intel.com> From: Paolo Bonzini Message-ID: <42da32b0-6cb0-58e4-dbb0-484afbd48757@redhat.com> Date: Thu, 11 Jun 2020 02:07:03 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200610181453.GC18790@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/06/20 20:14, Sean Christopherson wrote: >> - /* setup delayed work */ >> + /* Arch specific code should not do async PF in this case */ >> + if (unlikely(kvm_is_error_hva(hva))) > This feels like it should be changed to a WARN_ON_ONCE in a follow-up. > With the WARN, the comment could probably be dropped. I think a race is possible in principle where the memslots are changed (for example) between s390's page fault handler and the gfn_to_hva call in kvm_arch_setup_async_pf. Queued both, thanks! Paolo