From patchwork Fri Nov 14 10:07:53 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andre Przywara X-Patchwork-Id: 5304611 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id BB0FB9F2ED for ; Fri, 14 Nov 2014 10:25:39 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C56FD20145 for ; Fri, 14 Nov 2014 10:25:38 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D50762011E for ; Fri, 14 Nov 2014 10:25:37 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XpE2G-0003nf-Fd; Fri, 14 Nov 2014 10:23:24 +0000 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XpE1Q-0003Lj-Vy for linux-arm-kernel@lists.infradead.org; Fri, 14 Nov 2014 10:22:34 +0000 Received: from e106785-lin.cambridge.arm.com ([10.1.203.161]) by cam-admin0.cambridge.arm.com (8.12.6/8.12.6) with ESMTP id sAEA83wx022993; Fri, 14 Nov 2014 10:08:04 GMT From: Andre Przywara To: christoffer.dall@linaro.org, marc.zyngier@arm.com Subject: [PATCH v4 09/19] arm/arm64: KVM: make the value of ICC_SRE_EL1 a per-VM variable Date: Fri, 14 Nov 2014 10:07:53 +0000 Message-Id: <1415959683-26027-10-git-send-email-andre.przywara@arm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1415959683-26027-1-git-send-email-andre.przywara@arm.com> References: <1415959683-26027-1-git-send-email-andre.przywara@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20141114_022233_406272_D3EB25F5 X-CRM114-Status: GOOD ( 15.05 ) X-Spam-Score: -6.0 (------) Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_LOW, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP ICC_SRE_EL1 is a system register allowing msr/mrs accesses to the GIC CPU interface for EL1 (guests). Currently we force it to 0, but for proper GICv3 support we have to allow guests to use it (depending on their selected virtual GIC model). So add ICC_SRE_EL1 to the list of saved/restored registers on a world switch, but actually disallow a guest to change it by only restoring a fixed, once-initialized value. This value depends on the GIC model userland has chosen for a guest. Signed-off-by: Andre Przywara Reviewed-by: Christoffer Dall --- Changelog v3...v4: - initialize variable on declaration arch/arm64/kernel/asm-offsets.c | 1 + arch/arm64/kvm/vgic-v3-switch.S | 14 +++++++++----- include/kvm/arm_vgic.h | 1 + virt/kvm/arm/vgic-v3.c | 8 ++++++-- 4 files changed, 17 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 9a9fce0..9d34486 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -140,6 +140,7 @@ int main(void) DEFINE(VGIC_V2_CPU_ELRSR, offsetof(struct vgic_cpu, vgic_v2.vgic_elrsr)); DEFINE(VGIC_V2_CPU_APR, offsetof(struct vgic_cpu, vgic_v2.vgic_apr)); DEFINE(VGIC_V2_CPU_LR, offsetof(struct vgic_cpu, vgic_v2.vgic_lr)); + DEFINE(VGIC_V3_CPU_SRE, offsetof(struct vgic_cpu, vgic_v3.vgic_sre)); DEFINE(VGIC_V3_CPU_HCR, offsetof(struct vgic_cpu, vgic_v3.vgic_hcr)); DEFINE(VGIC_V3_CPU_VMCR, offsetof(struct vgic_cpu, vgic_v3.vgic_vmcr)); DEFINE(VGIC_V3_CPU_MISR, offsetof(struct vgic_cpu, vgic_v3.vgic_misr)); diff --git a/arch/arm64/kvm/vgic-v3-switch.S b/arch/arm64/kvm/vgic-v3-switch.S index d160469..617a012 100644 --- a/arch/arm64/kvm/vgic-v3-switch.S +++ b/arch/arm64/kvm/vgic-v3-switch.S @@ -148,17 +148,18 @@ * x0: Register pointing to VCPU struct */ .macro restore_vgic_v3_state - // Disable SRE_EL1 access. Necessary, otherwise - // ICH_VMCR_EL2.VFIQEn becomes one, and FIQ happens... - msr_s ICC_SRE_EL1, xzr - isb - // Compute the address of struct vgic_cpu add x3, x0, #VCPU_VGIC_CPU // Restore all interesting registers ldr w4, [x3, #VGIC_V3_CPU_HCR] ldr w5, [x3, #VGIC_V3_CPU_VMCR] + ldr w25, [x3, #VGIC_V3_CPU_SRE] + + msr_s ICC_SRE_EL1, x25 + + // make sure SRE is valid before writing the other registers + isb msr_s ICH_HCR_EL2, x4 msr_s ICH_VMCR_EL2, x5 @@ -244,9 +245,12 @@ dsb sy // Prevent the guest from touching the GIC system registers + // if SRE isn't enabled for GICv3 emulation + cbnz x25, 1f mrs_s x5, ICC_SRE_EL2 and x5, x5, #~ICC_SRE_EL2_ENABLE msr_s ICC_SRE_EL2, x5 +1: .endm ENTRY(__save_vgic_v3_state) diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 09344ac..421833f 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -243,6 +243,7 @@ struct vgic_v3_cpu_if { #ifdef CONFIG_ARM_GIC_V3 u32 vgic_hcr; u32 vgic_vmcr; + u32 vgic_sre; /* Restored only, change ignored */ u32 vgic_misr; /* Saved only */ u32 vgic_eisr; /* Saved only */ u32 vgic_elrsr; /* Saved only */ diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c index acd256c7..a04d208 100644 --- a/virt/kvm/arm/vgic-v3.c +++ b/virt/kvm/arm/vgic-v3.c @@ -145,15 +145,19 @@ static void vgic_v3_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcrp) static void vgic_v3_enable(struct kvm_vcpu *vcpu) { + struct vgic_v3_cpu_if *vgic_v3 = &vcpu->arch.vgic_cpu.vgic_v3; + /* * By forcing VMCR to zero, the GIC will restore the binary * points to their reset values. Anything else resets to zero * anyway. */ - vcpu->arch.vgic_cpu.vgic_v3.vgic_vmcr = 0; + vgic_v3->vgic_vmcr = 0; + + vgic_v3->vgic_sre = 0; /* Get the show on the road... */ - vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr = ICH_HCR_EN; + vgic_v3->vgic_hcr = ICH_HCR_EN; } static const struct vgic_ops vgic_v3_ops = {