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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 4C3ACC433EF for ; Thu, 16 Sep 2021 21:45:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26EB46120E for ; Thu, 16 Sep 2021 21:45:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239308AbhIPVqz (ORCPT ); Thu, 16 Sep 2021 17:46:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234847AbhIPVqs (ORCPT ); Thu, 16 Sep 2021 17:46:48 -0400 Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8EB3DC061574 for ; Thu, 16 Sep 2021 14:45:27 -0700 (PDT) Received: by mail-pj1-x104a.google.com with SMTP id k1-20020a17090a590100b001971da53970so5961250pji.4 for ; Thu, 16 Sep 2021 14:45:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:message-id:mime-version:subject:from:to:cc; bh=R5NhbA+pjUVPZNfNHPtaYNtNYTv1h+ja92HfpRStBqA=; b=LlzVqBRk9HyqIgkEKwTRdfPTOIlc3qOVXfopYaEeFe9ZewruQYdODOZc8ASQp5OKCr Fl7/fBaZ6EHFKNXJ+xM1+VbZvBIswyWIiv0TEV7LOY++QwJvEVoGtioABjNg40Qn3TMA unYRCZZpwXzX+cv1A4dD/X6mHRxaNWtuNhCSi55oFbCJsobXuBQEfo5PI0WwyK3cL0a9 utyujJWR0SBfQ+Pg+0ED6h3oWQP7PTBC6Q/WhqqWFLJLRF+M+Eeqg2JkmSwEqDt9iPtb ribrRQ8TyqBF/g79W4DNfjSteKGfhXaqLR/r0oqZsHexVUqAxtuwTNvMRN/a1XIYDPSl 9bug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:message-id:mime-version:subject :from:to:cc; bh=R5NhbA+pjUVPZNfNHPtaYNtNYTv1h+ja92HfpRStBqA=; b=MKYzyZBI2fskpKtdk6FsGR9OJMvIDfOO44zVIGVUz4w+wQQhj7eoE5nFuE6/K2M8gf g7yjkbaAM0CeaLXZ18zLxSnVfaSozNEY9z3FlxvJZcpXtTIGmXK7IlPwI3d4vKzcW2Rv W/FwlHPK6zit4tKzPAqVwHC8/9gdOKTHFO5lf8FuPJCxDu/YrPwddkLyJ0oRid27LwdT 3W74BkYFNiq+iXgyyOHPr9gTqZjocNlsuDVu+43VBXAsIWkPu+x/+fL9Qxa2t2op0Zc7 V2FWSBerO1j8JSACkuhBEmWldCC2WNvRGKVc1IspsCmiO2Ym+tP5k9J6Ivv5XyRGPinF UTSw== X-Gm-Message-State: AOAM5324Go9v6KNc8jx7M0rvMuFNNjKr5oy0bLgU1XrXQCgCpb6TsOFT LVVn0u0Zqyje5XCDrQ4q/4KMrp7JUnIw X-Google-Smtp-Source: ABdhPJyJ3GLd7Y4KTIshP0TGJLp8e0qxBx7aK4BWozn5MOmt0QCKuiQq7LSf2MbjftzPa+72dT3WDDKPV4P0 X-Received: from mizhang-super.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:1071]) (user=mizhang job=sendgmr) by 2002:a17:90a:1a52:: with SMTP id 18mr17365103pjl.43.1631828726904; Thu, 16 Sep 2021 14:45:26 -0700 (PDT) Reply-To: Mingwei Zhang Date: Thu, 16 Sep 2021 21:45:22 +0000 Message-Id: <20210916214522.1560893-1-mizhang@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.33.0.464.g1972c5931b-goog Subject: [PATCH v2] KVM: SVM: fix missing sev_decommission() in sev_receive_start() From: Mingwei Zhang To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Alper Gun , Borislav Petkov , Brijesh Singh , David Rienjes , Marc Orr , John Allen , Peter Gonda , Tom Lendacky , Vipin Sharma , Mingwei Zhang Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org DECOMMISSION the current SEV context if binding an ASID fails after RECEIVE_START. Per AMD's SEV API, RECEIVE_START generates a new guest context and thus needs to be paired with DECOMMISSION: AMD SEV API v0.24 Section 1.3.3 "The RECEIVE_START command is the only command other than the LAUNCH_START command that generates a new guest context and guest handle." The missing DECOMMISSION can result in subsequent SEV launch failures due to insufficient resource. In particular, both LAUNCH_START and RECEIVE_START command will fail with SEV_RET_RESOURCE_LIMIT error. Note, LAUNCH_START suffered from the same bug, but was previously fixed by [1]. However, the same bug could come back to LAUNCH_START if RECEIVE_START part was not fixed. So add the sev_decommission() function in sev_receive_start. [1] commit 934002cd660b ("KVM: SVM: Call SEV Guest Decommission if ASID binding fails"). Cc: Alper Gun Cc: Borislav Petkov Cc: Brijesh Singh Cc: David Rienjes Cc: Marc Orr Cc: John Allen Cc: Peter Gonda Cc: Sean Christopherson Cc: Tom Lendacky Cc: Vipin Sharma Reviewed-by: Marc Orr Reviewed-by: Sean Christopherson Acked-by: Brijesh Singh Fixes: af43cbbf954b ("KVM: SVM: Add support for KVM_SEV_RECEIVE_START command") Signed-off-by: Mingwei Zhang --- arch/x86/kvm/svm/sev.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 75e0b21ad07c..55d8b9c933c3 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1397,8 +1397,10 @@ static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp) /* Bind ASID to this guest */ ret = sev_bind_asid(kvm, start.handle, error); - if (ret) + if (ret) { + sev_decommission(start.handle); goto e_free_session; + } params.handle = start.handle; if (copy_to_user((void __user *)(uintptr_t)argp->data, -- 2.33.0.464.g1972c5931b-goog