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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D02F4C636CC for ; Tue, 31 Jan 2023 09:49:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=drWJwiqcGkeAmXitvUt14uZ/ttzHwPtdG3oJjGqtVgY=; b=JlLSp7nuqPj6Ut raDq08KSMH3aAS20LGMUpY8n1TM97+1FhlkG3GX0Ss7n2Rf1/2f/7Lm0r9gKW5Rqy3aeiyxWMMMiM yt2MswB0K2HBaO3nUCikDWZ7WbuYCgBoeNRlTrQ7ue8lhFnR7GkL2Nwi9eTDQL67BgIPcA3bx8CDs 6bU5Reg0G/N20w3qUSPw4I4OfPm5xITCDVgo+YR8JEHuJFhQZlzBRnLSJYq7QfEad+sbU/M6T8p+6 SLm9A8srCxGWeM1UkKV4TpVFa4BUDhtLgBILZwiKYDI15aZy17Yz1nbn3J28VntXCKPqky3/qxpDL N5bFd8/JYMZY8fLosiKg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pMnFk-0078Gt-F9; Tue, 31 Jan 2023 09:48:37 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pMn8W-00753P-8g for linux-arm-kernel@lists.infradead.org; Tue, 31 Jan 2023 09:41:12 +0000 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 dfw.source.kernel.org (Postfix) with ESMTPS id AAD5061445; Tue, 31 Jan 2023 09:41:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1FB0BC433D2; Tue, 31 Jan 2023 09:41:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675158067; bh=xBhjj6OSLXZCK722O+yY3j4d+austxISjMyQn27kvjI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a8LARrqCKSD/43xVEGLlmbmIpsKSaY3PaoONEIy1xkF8LYw+B1cftPEp2/bridyw5 2XbahgkGl1pZJ8/YgufHVAoqO4Yq/w8XowPIlyM+h1x09zbIECiaSWrA96dhVYbx+R JKZZlyj17tSpvr5/7CWZSSXgVGdyu8TYC6+B0bgADCOWRpoS/awGnhkQMbx1Y/K8lF 3QT5IFHJyT75jfRkAIUvRDo12GOf6wKijs16UuU2DxEYu4o8vtrkalpfkxJpPwvVLh EyV8MSWscrxzHulAJpn3dEbabGWIe/CnxY6BEsgTneCAGuEIDdhvPMF6UNzn/V5Ypl Y2k1DXIF0BKTA== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1pMmtS-0067U2-IH; Tue, 31 Jan 2023 09:25:34 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Alexandru Elisei , Andre Przywara , Chase Conklin , Christoffer Dall , Ganapatrao Kulkarni , Jintack Lim , Russell King , James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu Subject: [PATCH v8 18/69] KVM: arm64: nv: Emulate PSTATE.M for a guest hypervisor Date: Tue, 31 Jan 2023 09:24:13 +0000 Message-Id: <20230131092504.2880505-19-maz@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230131092504.2880505-1-maz@kernel.org> References: <20230131092504.2880505-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, alexandru.elisei@arm.com, andre.przywara@arm.com, chase.conklin@arm.com, christoffer.dall@arm.com, gankulkarni@os.amperecomputing.com, jintack@cs.columbia.edu, rmk+kernel@armlinux.org.uk, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230131_014108_449550_DC42632E X-CRM114-Status: GOOD ( 19.40 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org We can no longer blindly copy the VCPU's PSTATE into SPSR_EL2 and return to the guest and vice versa when taking an exception to the hypervisor, because we emulate virtual EL2 in EL1 and therefore have to translate the mode field from EL2 to EL1 and vice versa. This requires keeping track of the state we enter the guest, for which we transiently use a dedicated flag. Reviewed-by: Russell King (Oracle) Reviewed-by: Alexandru Elisei Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/kvm_host.h | 2 ++ arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 19 ++++++++++++++++- arch/arm64/kvm/hyp/vhe/switch.c | 24 ++++++++++++++++++++++ 3 files changed, 44 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 640997251724..a1892a8f6032 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -649,6 +649,8 @@ struct kvm_vcpu_arch { #define DEBUG_STATE_SAVE_SPE __vcpu_single_flag(iflags, BIT(5)) /* Save TRBE context if active */ #define DEBUG_STATE_SAVE_TRBE __vcpu_single_flag(iflags, BIT(6)) +/* vcpu running in HYP context */ +#define VCPU_HYP_CONTEXT __vcpu_single_flag(iflags, BIT(7)) /* SVE enabled for host EL0 */ #define HOST_SVE_ENABLED __vcpu_single_flag(sflags, BIT(0)) diff --git a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h index c506eabc4e21..d67c620f2af7 100644 --- a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h +++ b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h @@ -155,9 +155,26 @@ static inline void __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt, write_sysreg_el1(ctxt_sys_reg(ctxt, SPSR_EL1), SYS_SPSR); } +/* Read the VCPU state's PSTATE, but translate (v)EL2 to EL1. */ +static inline u64 to_hw_pstate(const struct kvm_cpu_context *ctxt) +{ + u64 mode = ctxt->regs.pstate & (PSR_MODE_MASK | PSR_MODE32_BIT); + + switch (mode) { + case PSR_MODE_EL2t: + mode = PSR_MODE_EL1t; + break; + case PSR_MODE_EL2h: + mode = PSR_MODE_EL1h; + break; + } + + return (ctxt->regs.pstate & ~(PSR_MODE_MASK | PSR_MODE32_BIT)) | mode; +} + static inline void __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctxt) { - u64 pstate = ctxt->regs.pstate; + u64 pstate = to_hw_pstate(ctxt); u64 mode = pstate & PSR_AA32_MODE_MASK; /* diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c index 81bf236d9c27..cd3f3117bf16 100644 --- a/arch/arm64/kvm/hyp/vhe/switch.c +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -120,6 +120,25 @@ static const exit_handler_fn *kvm_get_exit_handler_array(struct kvm_vcpu *vcpu) static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code) { + /* + * If we were in HYP context on entry, adjust the PSTATE view + * so that the usual helpers work correctly. + */ + if (unlikely(vcpu_get_flag(vcpu, VCPU_HYP_CONTEXT))) { + u64 mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT); + + switch (mode) { + case PSR_MODE_EL1t: + mode = PSR_MODE_EL2t; + break; + case PSR_MODE_EL1h: + mode = PSR_MODE_EL2h; + break; + } + + *vcpu_cpsr(vcpu) &= ~(PSR_MODE_MASK | PSR_MODE32_BIT); + *vcpu_cpsr(vcpu) |= mode; + } } /* Switch to the guest for VHE systems running in EL2 */ @@ -154,6 +173,11 @@ static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) sysreg_restore_guest_state_vhe(guest_ctxt); __debug_switch_to_guest(vcpu); + if (is_hyp_ctxt(vcpu)) + vcpu_set_flag(vcpu, VCPU_HYP_CONTEXT); + else + vcpu_clear_flag(vcpu, VCPU_HYP_CONTEXT); + do { /* Jump in the fire! */ exit_code = __guest_enter(vcpu); -- 2.34.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel