Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753246AbdL0QuC (ORCPT ); Wed, 27 Dec 2017 11:50:02 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:36670 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753186AbdL0Qt6 (ORCPT ); Wed, 27 Dec 2017 11:49:58 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julien Thierry , Christoffer Dall , Marc Zyngier , Catalin Marinas , Will Deacon Subject: [PATCH 4.14 57/74] arm64: kvm: Prevent restoring stale PMSCR_EL1 for vcpu Date: Wed, 27 Dec 2017 17:46:30 +0100 Message-Id: <20171227164616.440759140@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171227164614.109898944@linuxfoundation.org> References: <20171227164614.109898944@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1470 Lines: 43 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Julien Thierry commit bfe766cf65fb65e68c4764f76158718560bdcee5 upstream. When VHE is not present, KVM needs to save and restores PMSCR_EL1 when possible. If SPE is used by the host, value of PMSCR_EL1 cannot be saved for the guest. If the host starts using SPE between two save+restore on the same vcpu, restore will write the value of PMSCR_EL1 read during the first save. Make sure __debug_save_spe_nvhe clears the value of the saved PMSCR_EL1 when the guest cannot use SPE. Signed-off-by: Julien Thierry Cc: Christoffer Dall Cc: Marc Zyngier Cc: Catalin Marinas Reviewed-by: Will Deacon Reviewed-by: Christoffer Dall Signed-off-by: Christoffer Dall Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kvm/hyp/debug-sr.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/arm64/kvm/hyp/debug-sr.c +++ b/arch/arm64/kvm/hyp/debug-sr.c @@ -84,6 +84,9 @@ static void __hyp_text __debug_save_spe_ { u64 reg; + /* Clear pmscr in case of early return */ + *pmscr_el1 = 0; + /* SPE present on this CPU? */ if (!cpuid_feature_extract_unsigned_field(read_sysreg(id_aa64dfr0_el1), ID_AA64DFR0_PMSVER_SHIFT))