From patchwork Tue Feb 11 17:48:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 11376299 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 88DFF14B4 for ; Tue, 11 Feb 2020 17:53:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6927A214DB for ; Tue, 11 Feb 2020 17:53:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581443603; bh=sE8UXFGqcupDgYc8xZ/0fIPTLUj36A79kNsMxBbXn/o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=eroVvHP42UCCMSVn3BaZ38RCevZ0FVFbDBaZ5bp5AQxh3LC0Fcc+6G5qhdBcNTDOZ PgS4A+XGG20NBrLH5/ViXRwIZlnox7lno/qblmtYhx+Pfwg1uhbuffA5PEtdKRguxm 27b5wEsXDEOCkmg8oR5TPNii6u5HPzo+vKGadMj8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730662AbgBKRxW (ORCPT ); Tue, 11 Feb 2020 12:53:22 -0500 Received: from mail.kernel.org ([198.145.29.99]:56904 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730671AbgBKRxW (ORCPT ); Tue, 11 Feb 2020 12:53:22 -0500 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 48EC720661; Tue, 11 Feb 2020 17:53:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581443601; bh=sE8UXFGqcupDgYc8xZ/0fIPTLUj36A79kNsMxBbXn/o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eJBh7/n4oMrBfqjZFf2O0DAofX+KFPP1XKEJJTDfjhF3L7LboA2R8IDJ2w/EgRP/c ydpCPbog6g8EEZxa1TGFTi4JOO+qpV/xJwZjNIiBYoEjiC0Sic9Ay7x/admleXhi+K +z+uqoy4UaSNUsOqnfC1ptuwMgj7lQoLfjWQYCZ4= Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1j1Zfj-004O7k-Ej; Tue, 11 Feb 2020 17:50:07 +0000 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Cc: Andre Przywara , Christoffer Dall , Dave Martin , Jintack Lim , Alexandru Elisei , James Morse , Julien Thierry , Suzuki K Poulose Subject: [PATCH v2 24/94] KVM: arm64: nv: Respect virtual CPTR_EL2.{TFP,FPEN} settings Date: Tue, 11 Feb 2020 17:48:28 +0000 Message-Id: <20200211174938.27809-25-maz@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200211174938.27809-1-maz@kernel.org> References: <20200211174938.27809-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, andre.przywara@arm.com, christoffer.dall@arm.com, Dave.Martin@arm.com, jintack@cs.columbia.edu, alexandru.elisei@arm.com, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Jintack Lim Forward traps due to FP/ASIMD register accesses to the virtual EL2 if virtual CPTR_EL2.TFP is set (with HCR_EL2.E2H == 0) or CPTR_EL2.FPEN is configure to do so (with HCR_EL2.E2h == 1). Signed-off-by: Jintack Lim Signed-off-by: Christoffer Dall [maz: account for HCR_EL2.E2H when testing for TFP/FPEN, with all the hard work actually being done by Chase Conklin] Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_emulate.h | 26 ++++++++++++++++++++++++++ arch/arm64/kvm/handle_exit.c | 16 ++++++++++++---- arch/arm64/kvm/hyp/switch.c | 11 +++++++++-- 3 files changed, 47 insertions(+), 6 deletions(-) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 26552c8571cb..0e5f88060ecc 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -11,12 +11,14 @@ #ifndef __ARM64_KVM_EMULATE_H__ #define __ARM64_KVM_EMULATE_H__ +#include #include #include #include #include #include +#include #include #include #include @@ -392,6 +394,30 @@ static inline bool vcpu_mode_priv(const struct kvm_vcpu *vcpu) return mode != PSR_MODE_EL0t; } +static inline bool guest_hyp_fpsimd_traps_enabled(const struct kvm_vcpu *vcpu) +{ + u64 val; + + if (!nested_virt_in_use(vcpu)) + return false; + + val = vcpu_read_sys_reg(vcpu, CPTR_EL2); + + if (!vcpu_el2_e2h_is_set(vcpu)) + return (val & CPTR_EL2_TFP); + + switch (FIELD_GET(CPACR_EL1_FPEN, val)) { + case 0b00: + case 0b10: + return true; + case 0b01: + return vcpu_el2_tge_is_set(vcpu) && !vcpu_mode_el2(vcpu); + case 0b11: + default: /* GCC is dumb */ + return false; + } +} + static inline u32 kvm_vcpu_get_hsr(const struct kvm_vcpu *vcpu) { return vcpu->arch.fault.esr_el2; diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 03bc69b09ed4..e813bda18c7c 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -97,11 +97,19 @@ static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) } /* - * Guest access to FP/ASIMD registers are routed to this handler only - * when the system doesn't support FP/ASIMD. + * This handles the cases where the system does not support FP/ASIMD or when + * we are running nested virtualization and the guest hypervisor is trapping + * FP/ASIMD accesses by its guest guest. + * + * All other handling of guest vs. host FP/ASIMD register state is handled in + * fixup_guest_exit(). */ -static int handle_no_fpsimd(struct kvm_vcpu *vcpu, struct kvm_run *run) +static int kvm_handle_fpasimd(struct kvm_vcpu *vcpu, struct kvm_run *run) { + if (guest_hyp_fpsimd_traps_enabled(vcpu)) + return kvm_inject_nested_sync(vcpu, kvm_vcpu_get_hsr(vcpu)); + + /* This is the case when the system doesn't support FP/ASIMD. */ kvm_inject_undefined(vcpu); return 1; } @@ -270,7 +278,7 @@ static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_BREAKPT_LOW]= kvm_handle_guest_debug, [ESR_ELx_EC_BKPT32] = kvm_handle_guest_debug, [ESR_ELx_EC_BRK64] = kvm_handle_guest_debug, - [ESR_ELx_EC_FP_ASIMD] = handle_no_fpsimd, + [ESR_ELx_EC_FP_ASIMD] = kvm_handle_fpasimd, [ESR_ELx_EC_PAC] = kvm_handle_ptrauth, }; diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 976b9661203b..ae967e274e08 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -371,11 +371,18 @@ static bool __hyp_text __hyp_handle_fpsimd(struct kvm_vcpu *vcpu) hsr_ec != ESR_ELx_EC_SVE) return false; - /* Don't handle SVE traps for non-SVE vcpus here: */ - if (!sve_guest) + /* + * Don't handle SVE traps for non-SVE vcpus here. This + * includes NV guests for the time beeing. + */ + if (!sve_guest) { if (hsr_ec != ESR_ELx_EC_FP_ASIMD) return false; + if (guest_hyp_fpsimd_traps_enabled(vcpu)) + return false; + } + /* Valid trap. Switch the context: */ if (vhe) {