From patchwork Mon May 15 17:30:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13241909 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 ECE9AC77B7D for ; Mon, 15 May 2023 17:49:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244791AbjEORtO (ORCPT ); Mon, 15 May 2023 13:49:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46596 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244128AbjEORsi (ORCPT ); Mon, 15 May 2023 13:48:38 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ADEFF183CA for ; Mon, 15 May 2023 10:47:03 -0700 (PDT) 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 8D8E362F08 for ; Mon, 15 May 2023 17:47:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D2455C4339B; Mon, 15 May 2023 17:47:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684172823; bh=si0pj4eLKvyGEpWT8F2+2OVmTMIOYM63o1TwN/EyzSQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=e4RxxI8Xkuv4eDBfvHkbk3ywaB93eTtx+sJi+xcx13XOUtU9wHj3xgO4ZswwDkQZ2 7QMkOr4Fo9ZrClwNuwN5HKEiIP6Qw2xazpNTFjm9nDQodyxuMCnICnDPx9L9LEbfnN 4tgpcp8LkWfCGgWHD7btRK4/47/nVFyt1jcd58AKoruSebXFWrgGoTsnEbMWRyv2al SDjjYKllDUROt6CQzf3wcQeO89q2VT4hiNo+fTr1fKFWSsdhW+exMzVifAdDGva51O OqqJncQyopLrDxahkGaCMHjDCIitCDijK175pvoyExM7VNhkfXOMGoTIxMa0CGhW2f UhepKSdeHSMsw== 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 1pyc2i-00FJAF-2P; Mon, 15 May 2023 18:31:28 +0100 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 , Darren Hart , Jintack Lim , Russell King , Miguel Luis , James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu Subject: [PATCH v10 18/59] KVM: arm64: nv: Save/Restore vEL2 sysregs Date: Mon, 15 May 2023 18:30:22 +0100 Message-Id: <20230515173103.1017669-19-maz@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230515173103.1017669-1-maz@kernel.org> References: <20230515173103.1017669-1-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, darren@os.amperecomputing.com, jintack@cs.columbia.edu, rmk+kernel@armlinux.org.uk, miguel.luis@oracle.com, 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 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Whenever we need to restore the guest's system registers to the CPU, we now need to take care of the EL2 system registers as well. Most of them are accessed via traps only, but some have an immediate effect and also a guest running in VHE mode would expect them to be accessible via their EL1 encoding, which we do not trap. For vEL2 we write the virtual EL2 registers with an identical format directly into their EL1 counterpart, and translate the few registers that have a different format for the same effect on the execution when running a non-VHE guest guest hypervisor. Based on an initial patch from Andre Przywara, rewritten many times since. Reviewed-by: Alexandru Elisei Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 5 +- arch/arm64/kvm/hyp/nvhe/sysreg-sr.c | 2 +- arch/arm64/kvm/hyp/vhe/sysreg-sr.c | 124 ++++++++++++++++++++- 3 files changed, 126 insertions(+), 5 deletions(-) diff --git a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h index 699ea1f8d409..d67c620f2af7 100644 --- a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h +++ b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h @@ -91,9 +91,10 @@ static inline void __sysreg_restore_user_state(struct kvm_cpu_context *ctxt) write_sysreg(ctxt_sys_reg(ctxt, TPIDRRO_EL0), tpidrro_el0); } -static inline void __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) +static inline void __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt, + u64 mpidr) { - write_sysreg(ctxt_sys_reg(ctxt, MPIDR_EL1), vmpidr_el2); + write_sysreg(mpidr, vmpidr_el2); if (has_vhe() || !cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { diff --git a/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c b/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c index 29305022bc04..dba101565de3 100644 --- a/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c +++ b/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c @@ -28,7 +28,7 @@ void __sysreg_save_state_nvhe(struct kvm_cpu_context *ctxt) void __sysreg_restore_state_nvhe(struct kvm_cpu_context *ctxt) { - __sysreg_restore_el1_state(ctxt); + __sysreg_restore_el1_state(ctxt, ctxt_sys_reg(ctxt, MPIDR_EL1)); __sysreg_restore_common_state(ctxt); __sysreg_restore_user_state(ctxt); __sysreg_restore_el2_return_state(ctxt); diff --git a/arch/arm64/kvm/hyp/vhe/sysreg-sr.c b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c index b35a178e7e0d..cae3e35a9034 100644 --- a/arch/arm64/kvm/hyp/vhe/sysreg-sr.c +++ b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c @@ -15,6 +15,95 @@ #include #include +static void __sysreg_save_vel2_state(struct kvm_cpu_context *ctxt) +{ + /* These registers are common with EL1 */ + ctxt_sys_reg(ctxt, PAR_EL1) = read_sysreg(par_el1); + ctxt_sys_reg(ctxt, TPIDR_EL1) = read_sysreg(tpidr_el1); + + ctxt_sys_reg(ctxt, ESR_EL2) = read_sysreg_el1(SYS_ESR); + ctxt_sys_reg(ctxt, AFSR0_EL2) = read_sysreg_el1(SYS_AFSR0); + ctxt_sys_reg(ctxt, AFSR1_EL2) = read_sysreg_el1(SYS_AFSR1); + ctxt_sys_reg(ctxt, FAR_EL2) = read_sysreg_el1(SYS_FAR); + ctxt_sys_reg(ctxt, MAIR_EL2) = read_sysreg_el1(SYS_MAIR); + ctxt_sys_reg(ctxt, VBAR_EL2) = read_sysreg_el1(SYS_VBAR); + ctxt_sys_reg(ctxt, CONTEXTIDR_EL2) = read_sysreg_el1(SYS_CONTEXTIDR); + ctxt_sys_reg(ctxt, AMAIR_EL2) = read_sysreg_el1(SYS_AMAIR); + + /* + * In VHE mode those registers are compatible between EL1 and EL2, + * and the guest uses the _EL1 versions on the CPU naturally. + * So we save them into their _EL2 versions here. + * For nVHE mode we trap accesses to those registers, so our + * _EL2 copy in sys_regs[] is always up-to-date and we don't need + * to save anything here. + */ + if (__vcpu_el2_e2h_is_set(ctxt)) { + ctxt_sys_reg(ctxt, SCTLR_EL2) = read_sysreg_el1(SYS_SCTLR); + ctxt_sys_reg(ctxt, CPTR_EL2) = read_sysreg_el1(SYS_CPACR); + ctxt_sys_reg(ctxt, TTBR0_EL2) = read_sysreg_el1(SYS_TTBR0); + ctxt_sys_reg(ctxt, TTBR1_EL2) = read_sysreg_el1(SYS_TTBR1); + ctxt_sys_reg(ctxt, TCR_EL2) = read_sysreg_el1(SYS_TCR); + ctxt_sys_reg(ctxt, CNTHCTL_EL2) = read_sysreg_el1(SYS_CNTKCTL); + } + + ctxt_sys_reg(ctxt, SP_EL2) = read_sysreg(sp_el1); + ctxt_sys_reg(ctxt, ELR_EL2) = read_sysreg_el1(SYS_ELR); + ctxt_sys_reg(ctxt, SPSR_EL2) = __fixup_spsr_el2_read(ctxt, read_sysreg_el1(SYS_SPSR)); +} + +static void __sysreg_restore_vel2_state(struct kvm_cpu_context *ctxt) +{ + u64 val; + + /* These registers are common with EL1 */ + write_sysreg(ctxt_sys_reg(ctxt, PAR_EL1), par_el1); + write_sysreg(ctxt_sys_reg(ctxt, TPIDR_EL1), tpidr_el1); + + write_sysreg(read_cpuid_id(), vpidr_el2); + write_sysreg(ctxt_sys_reg(ctxt, MPIDR_EL1), vmpidr_el2); + write_sysreg_el1(ctxt_sys_reg(ctxt, MAIR_EL2), SYS_MAIR); + write_sysreg_el1(ctxt_sys_reg(ctxt, VBAR_EL2), SYS_VBAR); + write_sysreg_el1(ctxt_sys_reg(ctxt, CONTEXTIDR_EL2),SYS_CONTEXTIDR); + write_sysreg_el1(ctxt_sys_reg(ctxt, AMAIR_EL2), SYS_AMAIR); + + if (__vcpu_el2_e2h_is_set(ctxt)) { + /* + * In VHE mode those registers are compatible between + * EL1 and EL2. + */ + write_sysreg_el1(ctxt_sys_reg(ctxt, SCTLR_EL2), SYS_SCTLR); + write_sysreg_el1(ctxt_sys_reg(ctxt, CPTR_EL2), SYS_CPACR); + write_sysreg_el1(ctxt_sys_reg(ctxt, TTBR0_EL2), SYS_TTBR0); + write_sysreg_el1(ctxt_sys_reg(ctxt, TTBR1_EL2), SYS_TTBR1); + write_sysreg_el1(ctxt_sys_reg(ctxt, TCR_EL2), SYS_TCR); + write_sysreg_el1(ctxt_sys_reg(ctxt, CNTHCTL_EL2), SYS_CNTKCTL); + } else { + /* + * CNTHCTL_EL2 only affects EL1 when running nVHE, so + * no need to restore it. + */ + val = translate_sctlr_el2_to_sctlr_el1(ctxt_sys_reg(ctxt, SCTLR_EL2)); + write_sysreg_el1(val, SYS_SCTLR); + val = translate_cptr_el2_to_cpacr_el1(ctxt_sys_reg(ctxt, CPTR_EL2)); + write_sysreg_el1(val, SYS_CPACR); + val = translate_ttbr0_el2_to_ttbr0_el1(ctxt_sys_reg(ctxt, TTBR0_EL2)); + write_sysreg_el1(val, SYS_TTBR0); + val = translate_tcr_el2_to_tcr_el1(ctxt_sys_reg(ctxt, TCR_EL2)); + write_sysreg_el1(val, SYS_TCR); + } + + write_sysreg_el1(ctxt_sys_reg(ctxt, ESR_EL2), SYS_ESR); + write_sysreg_el1(ctxt_sys_reg(ctxt, AFSR0_EL2), SYS_AFSR0); + write_sysreg_el1(ctxt_sys_reg(ctxt, AFSR1_EL2), SYS_AFSR1); + write_sysreg_el1(ctxt_sys_reg(ctxt, FAR_EL2), SYS_FAR); + write_sysreg(ctxt_sys_reg(ctxt, SP_EL2), sp_el1); + write_sysreg_el1(ctxt_sys_reg(ctxt, ELR_EL2), SYS_ELR); + + val = __fixup_spsr_el2_write(ctxt, ctxt_sys_reg(ctxt, SPSR_EL2)); + write_sysreg_el1(val, SYS_SPSR); +} + /* * VHE: Host and guest must save mdscr_el1 and sp_el0 (and the PC and * pstate, which are handled as part of the el2 return state) on every @@ -66,6 +155,7 @@ void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu) { struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt; struct kvm_cpu_context *host_ctxt; + u64 mpidr; host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; __sysreg_save_user_state(host_ctxt); @@ -89,7 +179,29 @@ void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu) */ __sysreg32_restore_state(vcpu); __sysreg_restore_user_state(guest_ctxt); - __sysreg_restore_el1_state(guest_ctxt); + + if (unlikely(__is_hyp_ctxt(guest_ctxt))) { + __sysreg_restore_vel2_state(guest_ctxt); + } else { + if (vcpu_has_nv(vcpu)) { + /* + * Only set VPIDR_EL2 for nested VMs, as this is the + * only time it changes. We'll restore the MIDR_EL1 + * view on put. + */ + write_sysreg(ctxt_sys_reg(guest_ctxt, VPIDR_EL2), vpidr_el2); + + /* + * As we're restoring a nested guest, set the value + * provided by the guest hypervisor. + */ + mpidr = ctxt_sys_reg(guest_ctxt, VMPIDR_EL2); + } else { + mpidr = ctxt_sys_reg(guest_ctxt, MPIDR_EL1); + } + + __sysreg_restore_el1_state(guest_ctxt, mpidr); + } vcpu_set_flag(vcpu, SYSREGS_ON_CPU); @@ -115,12 +227,20 @@ void kvm_vcpu_put_sysregs_vhe(struct kvm_vcpu *vcpu) host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; deactivate_traps_vhe_put(vcpu); - __sysreg_save_el1_state(guest_ctxt); + if (unlikely(__is_hyp_ctxt(guest_ctxt))) + __sysreg_save_vel2_state(guest_ctxt); + else + __sysreg_save_el1_state(guest_ctxt); + __sysreg_save_user_state(guest_ctxt); __sysreg32_save_state(vcpu); /* Restore host user state */ __sysreg_restore_user_state(host_ctxt); + /* If leaving a nesting guest, restore MPIDR_EL1 default view */ + if (vcpu_has_nv(vcpu)) + write_sysreg(read_cpuid_id(), vpidr_el2); + vcpu_clear_flag(vcpu, SYSREGS_ON_CPU); }