From patchwork Thu Apr 8 11:43:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Emanuele Giuseppe Esposito X-Patchwork-Id: 12190783 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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 4F265C43460 for ; Thu, 8 Apr 2021 11:43:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3351C61155 for ; Thu, 8 Apr 2021 11:43:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231345AbhDHLoH (ORCPT ); Thu, 8 Apr 2021 07:44:07 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:50568 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231266AbhDHLoF (ORCPT ); Thu, 8 Apr 2021 07:44:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617882234; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=i9iBaLNrNdHy5Myw5Ru7jrMYIVd0xBvqef8GrfatpKg=; b=ZzhLaX7XVlHnNA98G3ayqHGPO7DXUh7luxQZKKv92xktPJBKLi/wRdYavGcPr9mWuDFTfi zZeLJLC/BsNj25uPdd5BSELOuxIv/L67MaCcV3QG1ZifrZF+Hbsk6U5H1Zs7bUWqbb+98A mTGwvSnbkT1BhFhC/4hyEA1nMNqGLaA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-155-RoBmdd_GPzeBTTdDIISv6A-1; Thu, 08 Apr 2021 07:43:50 -0400 X-MC-Unique: RoBmdd_GPzeBTTdDIISv6A-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D931B1883525; Thu, 8 Apr 2021 11:43:48 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-113-155.ams2.redhat.com [10.36.113.155]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7A6C45B4A8; Thu, 8 Apr 2021 11:43:31 +0000 (UTC) From: Emanuele Giuseppe Esposito To: kvm@vger.kernel.org Cc: Paolo Bonzini , Jonathan Corbet , Sean Christopherson , Vitaly Kuznetsov , Emanuele Giuseppe Esposito , Jim Mattson , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Shuah Khan , Alexander Graf , Andrew Jones , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH v4 2/4] Documentation: KVM: update KVM_GET_EMULATED_CPUID ioctl description Date: Thu, 8 Apr 2021 13:43:01 +0200 Message-Id: <20210408114303.30310-3-eesposit@redhat.com> In-Reply-To: <20210408114303.30310-1-eesposit@redhat.com> References: <20210408114303.30310-1-eesposit@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org KVM_GET_EMULATED_CPUID returns -E2BIG if the nent field of struct kvm_cpuid2 is smaller than the actual entries, while it adjusts nent if the provided amount is bigger than the actual amount. Update documentation accordingly. ENOMEM is just returned if the allocation fails, like all other calls. Signed-off-by: Emanuele Giuseppe Esposito --- Documentation/virt/kvm/api.rst | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 307f2fcf1b02..8ba23bc2a625 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -3404,12 +3404,10 @@ which features are emulated by kvm instead of being present natively. Userspace invokes KVM_GET_EMULATED_CPUID by passing a kvm_cpuid2 structure with the 'nent' field indicating the number of entries in -the variable-size array 'entries'. If the number of entries is too low -to describe the cpu capabilities, an error (E2BIG) is returned. If the -number is too high, the 'nent' field is adjusted and an error (ENOMEM) -is returned. If the number is just right, the 'nent' field is adjusted -to the number of valid entries in the 'entries' array, which is then -filled. +the variable-size array 'entries'. +If the number of entries is too low to describe the cpu +capabilities, an error (E2BIG) is returned. If the number is too high, +the 'nent' field is adjusted and the entries array is filled. The entries returned are the set CPUID bits of the respective features which kvm emulates, as returned by the CPUID instruction, with unknown