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 7D12AC433ED for ; Wed, 21 Apr 2021 17:52:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 481656141C for ; Wed, 21 Apr 2021 17:52:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245036AbhDURwu (ORCPT ); Wed, 21 Apr 2021 13:52:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239610AbhDURwu (ORCPT ); Wed, 21 Apr 2021 13:52:50 -0400 Received: from mail-pf1-x436.google.com (mail-pf1-x436.google.com [IPv6:2607:f8b0:4864:20::436]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A2B42C06174A for ; Wed, 21 Apr 2021 10:52:16 -0700 (PDT) Received: by mail-pf1-x436.google.com with SMTP id c3so10793621pfo.3 for ; Wed, 21 Apr 2021 10:52:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=j0oNgrMS6c/o4IGah+hGa4+DPYaNs5vsM0yBA9s/Ipc=; b=PC9rmVZOSQtON+ffsnFdk3VaEQKGIV1CRsgOXmNCX0j2YQoCoyoeulAFRgBen0GnBR ValLl2k3iCMLTpZWuQt2AeeoPHDCGI1MrKud96kMoeTE13V1yWAN3n0kv2hvIACvUhRc +GknI9wuuIsQWZ/8zRe9qGcRJSF7cFUFtx/TD0X4CI37ckPr3bLAEd2KUDP8HnGae+Jh Ca9YYQQrttXuLty6496WwEXlNLjl4pmlgAB0XC7xreic+PHV1MNbEoWCETaba1iK0Tki rQaVfXr4LLWfLfsW7p1QRYKDHRKDTjOfHOSbLS2u22QVxm3wKBAPoqFbpD5MJ5A68SgH 6H8g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=j0oNgrMS6c/o4IGah+hGa4+DPYaNs5vsM0yBA9s/Ipc=; b=LkWNc6hifOV4pJaS+ie6S0hYSWHXFPdnxf7PQsR1o/jym5jdTkOg9XslGSBYalWS6x F1hLNTmyraYsl9QatbsUYVKah/LOKLBV9UNBxEeDda7jBb6t0w3ESIERxCdNPm3144TM HSQDsv7xsnCJzQzGC55Y0rlTiTVvGk3+MhukkvPHLdpBCjBxdu4rmiI6NE4Rv32vqe/I kMP8fhxhfFwue8Xv9RIj3opAdXtBs5GgNmFjYS+HjYKWubWjAisrpuLfV6+ROVedJVYU 4C8Ze50VI3N9LYAaVAWHafEIZwE2u/50lSMuQX4Wr8i/0zVDGKdXOuI/ZvGEE4fQSml7 +huw== X-Gm-Message-State: AOAM532Fxv0Bgn/ZSO4ZRtW9oLkhuCjoKP3UYs9DjVCuJ8I8+hdVRqbf +RhCks6zP5/9jz1iUQxD2SOEmL/e7W/b6Q== X-Google-Smtp-Source: ABdhPJxVXoC5+0imRpjdl85DyBHQKbAgh+4ULrJoroIpLVkcIsrUXCvoomrZu1BwmXDOs1Vl/fym4g== X-Received: by 2002:a62:4d86:0:b029:252:c889:2dd8 with SMTP id a128-20020a624d860000b0290252c8892dd8mr31810996pfb.41.1619027536036; Wed, 21 Apr 2021 10:52:16 -0700 (PDT) Received: from google.com (240.111.247.35.bc.googleusercontent.com. [35.247.111.240]) by smtp.gmail.com with ESMTPSA id p12sm2829221pjo.4.2021.04.21.10.52.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Apr 2021 10:52:15 -0700 (PDT) Date: Wed, 21 Apr 2021 17:52:11 +0000 From: Sean Christopherson To: Aaron Lewis Cc: david.edmondson@oracle.com, jmattson@google.com, kvm@vger.kernel.org Subject: Re: [PATCH v3 1/2] kvm: x86: Allow userspace to handle emulation errors Message-ID: References: <20210421162225.3924641-1-aaronlewis@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210421162225.3924641-1-aaronlewis@google.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Please wait at least a day between versions to give everyone a chance to review the latest information and digest other folks' comments. Even a single day is a bit too frequent in most cases, especially for a series where people are actively commenting on the changes, as is the case here. I.e. give the current conversation a chance to run its course before spawning a new thread. Exceptions are few and far between, e.g. if you completely botched something and there's no point in having people review the current versions. Also, please include a cover letter with a synopsis of the delta between versions. Without that, reviewers have no idea what's different in v1 vs. v2 vs. v3 vs. vN, which increases the burden on reviewers. The delta information is especially helpful if other reviewers join the conversation at a later point. On Wed, Apr 21, 2021, 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