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 6D75EC433B4 for ; Fri, 9 Apr 2021 17:33:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4583F6115B for ; Fri, 9 Apr 2021 17:33:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234330AbhDIRdS (ORCPT ); Fri, 9 Apr 2021 13:33:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:38916 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234268AbhDIRdR (ORCPT ); Fri, 9 Apr 2021 13:33:17 -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 94D8B6103E; Fri, 9 Apr 2021 17:33:04 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1lUv0A-006ahk-HY; Fri, 09 Apr 2021 18:33:02 +0100 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu Cc: James Morse , Suzuki K Poulose , Alexandru Elisei , Will Deacon , kernel-team@android.com, stable@vger.kernel.org Subject: [PATCH v2] KVM: arm64: Fully zero the vcpu state on reset Date: Fri, 9 Apr 2021 18:32:57 +0100 Message-Id: <20210409173257.3031729-1-maz@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@arm.com, will@kernel.org, kernel-team@android.com, stable@vger.kernel.org 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: kvm@vger.kernel.org On vcpu reset, we expect all the registers to be brought back to their initial state, which happens to be a bunch of zeroes. However, some recent commit broke this, and is now leaving a bunch of registers (such as the FP state) with whatever was left by the guest. My bad. Zero the reset of the state (32bit SPSRs and FPSIMD state). Cc: stable@vger.kernel.org Fixes: e47c2055c68e ("KVM: arm64: Make struct kvm_regs userspace-only") Signed-off-by: Marc Zyngier --- Notes: v2: Only reset the FPSIMD state and the AArch32 SPSRs to avoid corrupting CNTVOFF in creative ways. arch/arm64/kvm/reset.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index bd354cd45d28..4b5acd84b8c8 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -242,6 +242,11 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) /* Reset core registers */ memset(vcpu_gp_regs(vcpu), 0, sizeof(*vcpu_gp_regs(vcpu))); + memset(&vcpu->arch.ctxt.fp_regs, 0, sizeof(vcpu->arch.ctxt.fp_regs)); + vcpu->arch.ctxt.spsr_abt = 0; + vcpu->arch.ctxt.spsr_und = 0; + vcpu->arch.ctxt.spsr_irq = 0; + vcpu->arch.ctxt.spsr_fiq = 0; vcpu_gp_regs(vcpu)->pstate = pstate; /* Reset system registers */ -- 2.30.2