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 6675AC4332F for ; Wed, 6 Apr 2022 21:53:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237084AbiDFVzn (ORCPT ); Wed, 6 Apr 2022 17:55:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35670 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236568AbiDFVzM (ORCPT ); Wed, 6 Apr 2022 17:55:12 -0400 Received: from mail-pg1-x52c.google.com (mail-pg1-x52c.google.com [IPv6:2607:f8b0:4864:20::52c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49A171020 for ; Wed, 6 Apr 2022 14:51:19 -0700 (PDT) Received: by mail-pg1-x52c.google.com with SMTP id 125so3273934pgc.11 for ; Wed, 06 Apr 2022 14:51:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=koQM8xA2BKIxu931jCtUHEyhwLbWyOVNzrZPe0cdI/o=; b=ka9C/dorFhtBGF6m0S4WRAgqeIS4O1JcWK7BIfF8pO0RIWWymKpAk0m69qYEPmQSYD f1D+C6J2lR7YYsDak7etINqttBK6G76/911kW6J0+X9+8N/z5C8QkpRM3DE4YH53OcOg rN5vNRYfxEchcX5qh59JIjHcdafZnWBNyp1q2GI/bz/MpPDxwQQLqrSYj+UNIamGBuHf RwqLLmpneb/GGkJ6W71Hn2+Xf8lYlPc/9XpfQ8rC/PYEgkF5OMlHcswueTOs+iDLqCYR xS+aLAs67w6mL04J8XNeEN83QfoQbTaLSwgP1T5MI32YuEbI5RGVSm9CxtPB0Lgmf1eW /7yg== 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=koQM8xA2BKIxu931jCtUHEyhwLbWyOVNzrZPe0cdI/o=; b=tJ7tR10h3djz2DFodGDCj5HPQxT35MzGNikPCipQqiXGqoinIUo0IPiQOMoQAnW8V2 KOCM3EjueRR3IuwXk+dFyHAg1gb28qWEFHc508MheOzL0aLqGSGduPBSg0QwGGBEmbwm hWDd4lUX0YX10GebWlJ3TNa1QXIwlxDzTzXIhk9EjGmgUgpDve81I7QnXbOONpZTWDqk UNacMlWzRk37VcqWeVfTErBOfwQ/aWGBtIokT5epTXN5U7WOmoMonHxH2v+LPc2tjPQC wJWaoPvbQGsXiQLiAy+e2s+bK3+tZBApgSdX8Red9FxKt2nmSPk2DFzk9N9j/1NBKsHG zBdA== X-Gm-Message-State: AOAM533pYcMXjBAdY/QVnZpnf0mq9xEMgPuVsN3i3oDopWn51tuGIPx7 SrmoeZSSeoa5KfnlyLJQBwYW/g== X-Google-Smtp-Source: ABdhPJzyHPkhUgiuuxECQtttoEhHy3d6hStlo2vatAwsXuRttGOOXqmfjyACKSNWYEz1RbyDmt27uA== X-Received: by 2002:a05:6a00:140e:b0:4e1:c81a:625c with SMTP id l14-20020a056a00140e00b004e1c81a625cmr10858620pfu.39.1649281878633; Wed, 06 Apr 2022 14:51:18 -0700 (PDT) Received: from google.com (157.214.185.35.bc.googleusercontent.com. [35.185.214.157]) by smtp.gmail.com with ESMTPSA id j22-20020a056a00235600b004faed937407sm21782456pfj.19.2022.04.06.14.51.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 06 Apr 2022 14:51:17 -0700 (PDT) Date: Wed, 6 Apr 2022 21:51:14 +0000 From: Sean Christopherson To: Chenyi Qiang Cc: Paolo Bonzini , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Xiaoyao Li , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 1/3] KVM: X86: Save&restore the triple fault request Message-ID: References: <20220318074955.22428-1-chenyi.qiang@intel.com> <20220318074955.22428-2-chenyi.qiang@intel.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: kvm@vger.kernel.org On Tue, Apr 05, 2022, Sean Christopherson wrote: > On Fri, Mar 18, 2022, Chenyi Qiang wrote: > > @@ -4903,7 +4906,8 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, > > | KVM_VCPUEVENT_VALID_SIPI_VECTOR > > | KVM_VCPUEVENT_VALID_SHADOW > > | KVM_VCPUEVENT_VALID_SMM > > - | KVM_VCPUEVENT_VALID_PAYLOAD)) > > + | KVM_VCPUEVENT_VALID_PAYLOAD > > + | KVM_VCPUEVENT_TRIPLE_FAULT)) > > return -EINVAL; > > > > if (events->flags & KVM_VCPUEVENT_VALID_PAYLOAD) { > > @@ -4976,6 +4980,9 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, > > } > > } > > > > + if (events->flags & KVM_VCPUEVENT_TRIPLE_FAULT) > > + kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); > > + > > kvm_make_request(KVM_REQ_EVENT, vcpu); > > Looks correct, but this really needs a selftest, at least for the SET path since > the intent is to use that for the NOTIFY handling. Doesn't need to be super fancy, > e.g. do port I/O from L2, inject a triple fault, and verify L1 sees the appropriate > exit. It finally dawned on me why all the other events use two "flags", i.e. an actual flags entry of KVM_VCPUEVENT_VALID_* and then the value itself. Userspace needs to be able to _clear_ the request, not just set the request. So this needs to follow the existing pattern of adding a VALID flag and then yet another field to specify whether or not a triple fault is pending.