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=-18.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=ham 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 57D1AC47082 for ; Thu, 3 Jun 2021 20:35:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 32ECD613D7 for ; Thu, 3 Jun 2021 20:35:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229881AbhFCUhN (ORCPT ); Thu, 3 Jun 2021 16:37:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39358 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229617AbhFCUhN (ORCPT ); Thu, 3 Jun 2021 16:37:13 -0400 Received: from mail-ot1-x330.google.com (mail-ot1-x330.google.com [IPv6:2607:f8b0:4864:20::330]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35AC4C06174A for ; Thu, 3 Jun 2021 13:35:13 -0700 (PDT) Received: by mail-ot1-x330.google.com with SMTP id v27-20020a056830091bb02903cd67d40070so3934742ott.1 for ; Thu, 03 Jun 2021 13:35:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=t9xGNkcktSlF9kmlEuS8GcNEn+IOZ6s4YoIEwUCwV/M=; b=eQE+d+/kbXV8Atq1C+7kjrvp7Y1EMF5QaP8wrZEjF3l/EjiL4YPV8PkC2+culToXEX DgASp1WMO3dgdJ6l5VGG48P1KKiCBh4C6BrSrB5urMzFwBajVMy9CaLEFx6NFslP9F+u LZ6dMpyMmgO83LHuZuqqiZtwzzENk6BXZyd4JreCI59eZTwdukYB32VFo/q/zE34hl7o Gc3TSgXfcdxVezW8llFenxGu4I1IkuGRLZcMPKWt7hn3inzKd8dpP1E1L6GDeEo31X/2 y6Te+4FlVXgzB7ixkkvLq/n9vCcPve2E3QMzwCxnUDhabBUHfcLtytmzp3UkR3kWEg7z BGgw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=t9xGNkcktSlF9kmlEuS8GcNEn+IOZ6s4YoIEwUCwV/M=; b=IMWSNjVbCGORx1LV64u+omHx8vMpUeto8qjDTfm3y87atL6gUrofWxV1Xc9d4GJ4O+ VsVMZfxSary8eme5Hl+24xyyJc22h++/HsKnD6nX2SGjTJzsJBfqR14Fo9zZwlF3cmR8 OAvV+aFRSw80R5tg1ntcxA0IC4SQYQZufb76a3h5PQIC4QaK+4hIqoWGpb5EIHkImAUK XYpGy4l8ccXEuan1rGN+mIs6Nxyg0wnSh96dzLPu0YmQ1hGerkNKsbX+KKGyunic2ty/ rHfO4YmExMnhO3W8Aa9/68qUZOpIFZsmQj610aPpTYI73s9OlL/JcAnfZ2uSlURGH0f9 u8Mw== X-Gm-Message-State: AOAM533xb5sEdVYzDxX6cs2w67T0scKlBAb3WR7jmD3SYsaDyMO5SeAj ROBpTRP+O2NOA6UzyfCfYz716u3BsnXrbhN8njMcRw== X-Google-Smtp-Source: ABdhPJy7ZgQraA6Me1tT2Or+VqNh/R3lrXcKuAXA7Mtnuz77OH/8o3lMB4FRAdEj5GNBP+GO+yWKkp4Ko7qLdqIs+sc= X-Received: by 2002:a05:6830:2011:: with SMTP id e17mr915511otp.295.1622752512262; Thu, 03 Jun 2021 13:35:12 -0700 (PDT) MIME-Version: 1.0 References: <20210510144834.658457-1-aaronlewis@google.com> <20210510144834.658457-2-aaronlewis@google.com> In-Reply-To: <20210510144834.658457-2-aaronlewis@google.com> From: Jim Mattson Date: Thu, 3 Jun 2021 13:35:01 -0700 Message-ID: Subject: Re: [PATCH v6 1/2] kvm: x86: Allow userspace to handle emulation errors To: Aaron Lewis Cc: David Edmondson , Sean Christopherson , kvm list Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Mon, May 10, 2021 at 7:48 AM Aaron Lewis wrote: > > Add a fallback mechanism to the in-kernel instruction emulator that > allows userspace the opportunity to process an instruction the emulator > was unable to. When the in-kernel instruction emulator fails to process > an instruction it will either inject a #UD into the guest or exit to > userspace with exit reason KVM_INTERNAL_ERROR. This is because it does > not know how to proceed in an appropriate manner. This feature lets > userspace get involved to see if it can figure out a better path > forward. > > Signed-off-by: Aaron Lewis > Reviewed-by: David Edmondson Reviewed-by: Jim Mattson