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=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 817AFC47E4B for ; Thu, 15 Jul 2021 16:32:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 66239613F7 for ; Thu, 15 Jul 2021 16:32:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232230AbhGOQf1 (ORCPT ); Thu, 15 Jul 2021 12:35:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:43046 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231626AbhGOQfL (ORCPT ); Thu, 15 Jul 2021 12:35:11 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5B6E8613FC; Thu, 15 Jul 2021 16:32:18 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1m44HY-00DYjr-P8; Thu, 15 Jul 2021 17:32:16 +0100 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Cc: will@kernel.org, qperret@google.com, dbrazdil@google.com, Srivatsa Vaddagiri , Shanker R Donthineni , James Morse , Suzuki K Poulose , Alexandru Elisei , kernel-team@android.com Subject: [PATCH 06/16] KVM: arm64: Force a full unmap on vpcu reinit Date: Thu, 15 Jul 2021 17:31:49 +0100 Message-Id: <20210715163159.1480168-7-maz@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210715163159.1480168-1-maz@kernel.org> References: <20210715163159.1480168-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, will@kernel.org, qperret@google.com, dbrazdil@google.com, vatsa@codeaurora.org, sdonthineni@nvidia.com, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@arm.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As we now keep information in the S2PT, we must be careful not to keep it across a VM reboot, which could otherwise lead to interesting problems. Make sure that the S2 is completely discarded on reset of a vcpu, and remove the flag that enforces the MMIO check. Signed-off-by: Marc Zyngier --- arch/arm64/kvm/arm.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 97ab1512c44f..b0d2225190d2 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1096,12 +1096,18 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, * ensuring that the data side is always coherent. We still * need to invalidate the I-cache though, as FWB does *not* * imply CTR_EL0.DIC. + * + * If the MMIO guard was enabled, we pay the price of a full + * unmap to get back to a sane state (and clear the flag). */ if (vcpu->arch.has_run_once) { - if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) + if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB) || + test_bit(KVM_ARCH_FLAG_MMIO_GUARD, &vcpu->kvm->arch.flags)) stage2_unmap_vm(vcpu->kvm); else icache_inval_all_pou(); + + clear_bit(KVM_ARCH_FLAG_MMIO_GUARD, &vcpu->kvm->arch.flags); } vcpu_reset_hcr(vcpu); -- 2.30.2