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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 C4A1AC2B9F4 for ; Mon, 28 Jun 2021 14:39:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AA1EB61206 for ; Mon, 28 Jun 2021 14:39:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234743AbhF1OmD (ORCPT ); Mon, 28 Jun 2021 10:42:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:35966 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234568AbhF1Ocs (ORCPT ); Mon, 28 Jun 2021 10:32:48 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id AE21061C7C; Mon, 28 Jun 2021 14:27:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1624890467; bh=tkmf6/6OeAXh1cg0sElhxYdTTvOAK7Oe8FM4NgV8fu0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vOMvesBRrVhLoeED2XcnilWZCjlyJuR8Gla6vczLS13wxo8rXzOepZybpBb1oH0LY NUTlGtJtlf2cGIlwlZxbhrX9MSDMxJYzNOVBU3SYaHJRXLoM3pSt5zCHpD+sw/uKHS tmB4oDh7TSjNvEvmrgNZLmc2JJX7Q1Zh6Fh+6szKpmscIwl4TtpF5Tu5oGrF9BkeEu VlfL6OAhceZlKkmUSY9DlYqu/MD4+OmLNZNJxZcn6fNgeNd2QunZ7+ukyZKtrPAkNS DrFcTcIH/F7DMs8rU7HqCbLxjkd7agvCPE2wLbVeA1RNQoIbaXxH8u8cvLDWy07ff1 u+rxxQ7aqTVMg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Alper Gun , Peter Gonda , Marc Orr , Paolo Bonzini , Greg Kroah-Hartman Subject: [PATCH 5.10 093/101] KVM: SVM: Call SEV Guest Decommission if ASID binding fails Date: Mon, 28 Jun 2021 10:25:59 -0400 Message-Id: <20210628142607.32218-94-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210628142607.32218-1-sashal@kernel.org> References: <20210628142607.32218-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.10.47-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.10.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.10.47-rc1 X-KernelTest-Deadline: 2021-06-30T14:25+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alper Gun commit 934002cd660b035b926438244b4294e647507e13 upstream. Send SEV_CMD_DECOMMISSION command to PSP firmware if ASID binding fails. If a failure happens after a successful LAUNCH_START command, a decommission command should be executed. Otherwise, guest context will be unfreed inside the AMD SP. After the firmware will not have memory to allocate more SEV guest context, LAUNCH_START command will begin to fail with SEV_RET_RESOURCE_LIMIT error. The existing code calls decommission inside sev_unbind_asid, but it is not called if a failure happens before guest activation succeeds. If sev_bind_asid fails, decommission is never called. PSP firmware has a limit for the number of guests. If sev_asid_binding fails many times, PSP firmware will not have resources to create another guest context. Cc: stable@vger.kernel.org Fixes: 59414c989220 ("KVM: SVM: Add support for KVM_SEV_LAUNCH_START command") Reported-by: Peter Gonda Signed-off-by: Alper Gun Reviewed-by: Marc Orr Signed-off-by: Paolo Bonzini Message-Id: <20210610174604.2554090-1-alpergun@google.com> Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/svm/sev.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 16b10b9436dc..01547bdbfb06 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -130,9 +130,25 @@ static void sev_asid_free(int asid) mutex_unlock(&sev_bitmap_lock); } -static void sev_unbind_asid(struct kvm *kvm, unsigned int handle) +static void sev_decommission(unsigned int handle) { struct sev_data_decommission *decommission; + + if (!handle) + return; + + decommission = kzalloc(sizeof(*decommission), GFP_KERNEL); + if (!decommission) + return; + + decommission->handle = handle; + sev_guest_decommission(decommission, NULL); + + kfree(decommission); +} + +static void sev_unbind_asid(struct kvm *kvm, unsigned int handle) +{ struct sev_data_deactivate *data; if (!handle) @@ -152,15 +168,7 @@ static void sev_unbind_asid(struct kvm *kvm, unsigned int handle) kfree(data); - decommission = kzalloc(sizeof(*decommission), GFP_KERNEL); - if (!decommission) - return; - - /* decommission handle */ - decommission->handle = handle; - sev_guest_decommission(decommission, NULL); - - kfree(decommission); + sev_decommission(handle); } static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) @@ -288,8 +296,10 @@ static int sev_launch_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; + } /* return handle to userspace */ params.handle = start->handle; -- 2.30.2