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 979EDC7EE2A for ; Thu, 11 May 2023 23:33:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239506AbjEKXdF (ORCPT ); Thu, 11 May 2023 19:33:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39130 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238993AbjEKXdC (ORCPT ); Thu, 11 May 2023 19:33:02 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9197F5FD2 for ; Thu, 11 May 2023 16:33:00 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-b9a7e3fc659so20610077276.1 for ; Thu, 11 May 2023 16:33:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1683847980; x=1686439980; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=nS6iEDTOVPKXI4+UjpZyIPwKEGgdgovZohVYNbQWeU4=; b=m1mTn2XPoYvYXNYJmfzWbIDXWq4bYYqRuSCzsqBrmXOyn0iTSW1mGChChBz38nWBh0 /YSu9i0Bb6HmByvNbI7ZobUCRNgitVQYeYkZ28Olsr2kku2etC+KRSnaLV37gSC9NNoE J3UlQ9E/lehVq2TxQmiEHcWIyLQKKBpYYY+dBzQvNKqGITGF765K6JIP200Gg32JpwLO H+2eHiQq2bHEsJm3WaQW1ox9sUuCfjgkFLErfCQKAD4zQw1/4UOVGm8nGrJaI+HIZFdl 22Nup8SaEUuyrR8htD0XbmubnyMDg1dnO7tQPh1/wXKOgcuzyWMD1+1f2n3evlgiQJVg G4fw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683847980; x=1686439980; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=nS6iEDTOVPKXI4+UjpZyIPwKEGgdgovZohVYNbQWeU4=; b=W+asOyDmxHBBvkLOFvbl2933Nc31aeOp9FIyDgswXspKKGoy76mTU8tugdOcyau3Ez Dl77Qd+q3pagNJZm1HOx907X8CmeSelh34Mi32YEx/YmOZgt5GySHAN+0QVxa3cxtYnQ qFWLRbw5dbPhFxNg13gilh6BtPXAEx+XnJ0WBWKV5iOpWzk7SrtBb3W+h+Sm7RssrXpV IEnpmT4uzNv/CIn7ELQcw+wMiauS9CA2XcPF5S+FnQ/QRGIA+7PAqMX/uWAmpv9GLnvr qCmNVF+6H4694AX4LUuSbF7HWQptbukJis10GJA+N4wXcbiY4C7Vu+GzqXjkqTZJwTPC ZBcw== X-Gm-Message-State: AC+VfDxO+mHi9AEbtBgv5+88rJWa8dVyGSfeYYfRRW5bsOIH9UHM+Hv4 xrAiMT63KTjFwsPFfw8A0kJfKYS4Ais= X-Google-Smtp-Source: ACHHUZ6oeZZ4oIRO3xJnqGtROFKuNKUystxK+0hUJRXTtXXFtT43eUPsNAi2aQTXHdTD16qAMRx6ZKAEsJE= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a05:6902:188c:b0:b96:a18:1b4c with SMTP id cj12-20020a056902188c00b00b960a181b4cmr10800373ybb.13.1683847979833; Thu, 11 May 2023 16:32:59 -0700 (PDT) Date: Thu, 11 May 2023 16:32:58 -0700 In-Reply-To: Mime-Version: 1.0 References: <385016f9-e948-4f7f-8db3-24a0c0543b3d@amd.com> <55e5f02f-4c1f-e6b0-59ba-07abc4d3408f@amd.com> <81037a58-6b5c-cde4-79fe-3686d9b8a551@amd.com> <7fb25176-3752-1be3-66d4-a7f5a0e1617a@amd.com> <682c0bf9-ccf7-9660-21fe-925ef63c5fbb@amd.com> <4c642bd1-5f1c-292e-398f-eed699db590d@amd.com> <65cb8f0f-7e8b-6df6-6bb1-a9f1add027bb@amd.com> Message-ID: Subject: Re: [PATCH RFC v7 52/64] KVM: SVM: Provide support for SNP_GUEST_REQUEST NAE event From: Sean Christopherson To: Dionna Amalie Glaze Cc: Tom Lendacky , Alexey Kardashevskiy , Ashish Kalra , Michael Roth , kvm@vger.kernel.org, linux-coco@lists.linux.dev, linux-mm@kvack.org, linux-crypto@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, jroedel@suse.de, hpa@zytor.com, ardb@kernel.org, pbonzini@redhat.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, luto@kernel.org, dave.hansen@linux.intel.com, slp@redhat.com, pgonda@google.com, peterz@infradead.org, srinivas.pandruvada@linux.intel.com, rientjes@google.com, dovmurik@linux.ibm.com, tobin@ibm.com, bp@alien8.de, vbabka@suse.cz, kirill@shutemov.name, ak@linux.intel.com, tony.luck@intel.com, marcorr@google.com, sathyanarayanan.kuppuswamy@linux.intel.com, alpergun@google.com, dgilbert@redhat.com, jarkko@kernel.org, harald@profian.com, Brijesh Singh Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 11, 2023, Dionna Amalie Glaze wrote: > Would it be okay to request that we add a KVM stat for how often there > are GUEST_REQUEST_NAE exits? I think it'd be good for service > operators to get a better idea how valued the feature is. Heh, it's always ok to request something, but sometimes the answer will be no. And in the case, the answer is likely "no stat for you". A year or so ago, in the context of us (Google) trying to upstream a pile of stats, we (KVM folks) came to a rough consensus that KVM should only add upstream stats if they are relatively generic and (almost) universally useful[*]. IMO, a one-off stat for a specific exit reason is too narrowly focused, e.g. collecting information on all exit reasons is superior. And no, that won't be accepted upstream either, because for some environments gathering detailed information on all exits is too much overhead (also covered in the link). FWIW, we (GCE) plan on carrying stats like this in out-of-tree patches, i.e. your request for stats is likely something that would get accepted internally (if it isn't already captured through our generic stats collection). [*] https://lore.kernel.org/all/87czp0voqg.wl-maz@kernel.org