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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE2C2C433EF for ; Mon, 29 Nov 2021 21:38:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231268AbhK2Vlx (ORCPT ); Mon, 29 Nov 2021 16:41:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230286AbhK2Vjv (ORCPT ); Mon, 29 Nov 2021 16:39:51 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0DAF6C091D3B for ; Mon, 29 Nov 2021 12:07:39 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 5DFE9CE1682 for ; Mon, 29 Nov 2021 20:07:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC375C53FAD; Mon, 29 Nov 2021 20:07:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1638216455; bh=DG5uIX2bquWNN63M+COe51RmuG6Tckf1/Wal1EhHeWQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PgN2Z/OT8rVmyE94YzzntX/KUyOTHCZnRlRXDduWjQrOkZKgVv6yfHHBGolbg7Nqx 6bDu9wn/R9jJdYNFgupIxbU0za3fZrON2Ho/DvmeQQo8RNQcBl59h19dBQU1nkha7U NfGGcz77oIMxRDzLBUVM2qk5ydaEfvYKDbpzcfA7+8mEVbz/6SLhxo68cIQfSZy/fq AfSRGOI+FnYDqL2MxD7qVlXskidM4rvG2jn0PsgffeUxH3zvZHFhqCcOFCJAbJiH4i 0Tfk07PnuF6ndJjeES3rqAPN8kc0OT2Wi6Nzr4vncjjAbPTAfCrq/g8gJlP8uglu9L 1majtVC9ZYfKw== 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 1mrmqw-008gvR-CX; Mon, 29 Nov 2021 20:02:18 +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 , Jintack Lim , Haibo Xu , Ganapatrao Kulkarni , James Morse , Suzuki K Poulose , Alexandru Elisei , kernel-team@android.com Subject: [PATCH v5 28/69] KVM: arm64: nv: Respect virtual CPTR_EL2.{TFP,FPEN} settings Date: Mon, 29 Nov 2021 20:01:09 +0000 Message-Id: <20211129200150.351436-29-maz@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211129200150.351436-1-maz@kernel.org> References: <20211129200150.351436-1-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, andre.przywara@arm.com, christoffer.dall@arm.com, jintack@cs.columbia.edu, haibo.xu@linaro.org, gankulkarni@os.amperecomputing.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: 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/include/hyp/switch.h | 8 ++++++-- 3 files changed, 44 insertions(+), 6 deletions(-) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 2db11ff3fdad..105fb0d4a366 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 @@ -324,6 +326,30 @@ 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 __always_inline u32 kvm_vcpu_get_esr(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 68a9579aa13e..7721c7c36137 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -96,11 +96,19 @@ static int handle_smc(struct kvm_vcpu *vcpu) } /* - * 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) +static int kvm_handle_fpasimd(struct kvm_vcpu *vcpu) { + if (guest_hyp_fpsimd_traps_enabled(vcpu)) + return kvm_inject_nested_sync(vcpu, kvm_vcpu_get_esr(vcpu)); + + /* This is the case when the system doesn't support FP/ASIMD. */ kvm_inject_undefined(vcpu); return 1; } @@ -229,7 +237,7 @@ 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/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h index 0987abd4d57d..110b347f887a 100644 --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -184,8 +184,12 @@ static bool kvm_hyp_handle_fpsimd(struct kvm_vcpu *vcpu, u64 *exit_code) esr_ec = kvm_vcpu_trap_get_class(vcpu); - /* Don't handle SVE traps for non-SVE vcpus here: */ - if (!sve_guest && esr_ec != ESR_ELx_EC_FP_ASIMD) + /* + * Don't handle SVE traps for non-SVE vcpus here. This + * includes NV guests for the time being. + */ + if (!sve_guest && (esr_ec != ESR_ELx_EC_FP_ASIMD || + guest_hyp_fpsimd_traps_enabled(vcpu))) return false; /* Valid trap. Switch the context: */ -- 2.30.2