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 8F595CDB474 for ; Tue, 17 Oct 2023 11:23:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234469AbjJQLXu (ORCPT ); Tue, 17 Oct 2023 07:23:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60016 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232134AbjJQLXu (ORCPT ); Tue, 17 Oct 2023 07:23:50 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 76D0E9F for ; Tue, 17 Oct 2023 04:23:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1697541779; 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: in-reply-to:in-reply-to:references:references; bh=JZIOMgVsnsQ5sKVZOqavpWhaECufWLCgd9frv4CfF0A=; b=G511lPTH6K0BwQ48gp7x3nt0HU9WbgQH3gxqFiTblnOH+gKwGHtmB169Xnn5P+/g6E5Yjb 303CdsrlpHD57JGQrnpHyvn/fwDLf6Zq4/kOKJPvX88gSJ0YT1DVhrMf/741wEQziZKlEg QvLkmVkQprt1E+e0HTU5Ks61hPoQYjg= Received: from mail-ej1-f70.google.com (mail-ej1-f70.google.com [209.85.218.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-299-X3YoemzfPly4lSLwUjN6dg-1; Tue, 17 Oct 2023 07:22:58 -0400 X-MC-Unique: X3YoemzfPly4lSLwUjN6dg-1 Received: by mail-ej1-f70.google.com with SMTP id a640c23a62f3a-9ae686dafedso406944766b.3 for ; Tue, 17 Oct 2023 04:22:58 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697541777; x=1698146577; h=mime-version:message-id:date:references:in-reply-to:subject:cc:to :from:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=JZIOMgVsnsQ5sKVZOqavpWhaECufWLCgd9frv4CfF0A=; b=lTnKoFMnjNyojG2bBHMJfXpIUsOIuDRBhezzaSvnM+1ehuUL9l28YKWYNCKCHhcceZ NzTkS+uLLu/YChkMpfk54mOPyuHBu1TT5LmegTIfaQMeJJ4TPsiBwkqn5xgatAcXiw9o LsE1f0NUNFVbxPqoQoyOH52+H4iZiZFr9VGjyNRMKBuIWCQ6S0iNP6N98edm55LTYG6c pDw630QJmitCuxqpxSI2NB5d8n+4o1SGBD1dO8KXPNsMlJn+OugNGAYqzbX7Rwd0lYzQ WodnlsnAPOlbzMqmArDRJfXnVIAD3KrleFLScUVGSfqK4Gy+RfBantE/mtptkmsqJr0A iHeA== X-Gm-Message-State: AOJu0YyTPgJ0xEYmpB3+LJE5WCT5qq9LM2wBH7tP5b1ji6vYe6a9X8U3 fhl+l0aD+B/V157T9yMj0cHVTWLmGVCXplrDEiFXutVGzFaJaQT6U6/VR5vbGVW2dk95wdtr3+d /Q2Y8XYmhULqK X-Received: by 2002:a17:906:ef08:b0:9ba:65e:7529 with SMTP id f8-20020a170906ef0800b009ba065e7529mr1369391ejs.68.1697541777249; Tue, 17 Oct 2023 04:22:57 -0700 (PDT) X-Google-Smtp-Source: AGHT+IHOLUyvQoMWL9XFYq8RuPnMFLHZGBLDQoLys7Bbq0xQVsVm/PLnmF1v1E8g4wD+majZI5OU9g== X-Received: by 2002:a17:906:ef08:b0:9ba:65e:7529 with SMTP id f8-20020a170906ef0800b009ba065e7529mr1369381ejs.68.1697541776968; Tue, 17 Oct 2023 04:22:56 -0700 (PDT) Received: from fedora (g2.ign.cz. [91.219.240.8]) by smtp.gmail.com with ESMTPSA id o2-20020a170906358200b009a1dbf55665sm1053349ejb.161.2023.10.17.04.22.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Oct 2023 04:22:56 -0700 (PDT) From: Vitaly Kuznetsov To: Paolo Bonzini , Riccardo Mancini Cc: bataloe@amazon.com, graf@amazon.de, kvm@vger.kernel.org, Greg Farrell Subject: Re: [RFC PATCH 4.14] KVM: x86: Backport support for interrupt-based APF page-ready delivery in guest In-Reply-To: <62e17c67-953d-469f-84cf-a998a15a8926@redhat.com> References: <877co1cc5d.fsf@redhat.com> <20231013163640.14162-1-mancio@amazon.com> <87a5si8xcu.fsf@redhat.com> <62e17c67-953d-469f-84cf-a998a15a8926@redhat.com> Date: Tue, 17 Oct 2023 13:22:55 +0200 Message-ID: <87v8b57asw.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Paolo Bonzini writes: > On 10/16/23 16:18, Vitaly Kuznetsov wrote: >> In case keeping legacy mechanism is a must, I would suggest you somehow >> record the fact that the guest has opted for interrupt-based delivery >> (e.g. set a global variable or use a static key) and short-circuit >> do_async_page_fault() to immediately return and not do anything in this >> case. > > I guess you mean "not do anything for KVM_PV_REASON_PAGE_READY in this > case"? Yes, of course: KVM_PV_REASON_PAGE_NOT_PRESENT is always a #PF. -- Vitaly