From patchwork Fri Jun 29 11:15:39 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suzuki K Poulose X-Patchwork-Id: 10496279 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 75CC260230 for ; Fri, 29 Jun 2018 11:19:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6961A298DF for ; Fri, 29 Jun 2018 11:19:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5B78A298EE; Fri, 29 Jun 2018 11:19:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EBAF6298E7 for ; Fri, 29 Jun 2018 11:19:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934553AbeF2LSv (ORCPT ); Fri, 29 Jun 2018 07:18:51 -0400 Received: from foss.arm.com ([217.140.101.70]:60314 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934484AbeF2LRF (ORCPT ); Fri, 29 Jun 2018 07:17:05 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C94261529; Fri, 29 Jun 2018 04:17:04 -0700 (PDT) Received: from en101.cambridge.arm.com (en101.cambridge.arm.com [10.1.206.73]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 71C453F266; Fri, 29 Jun 2018 04:17:02 -0700 (PDT) From: Suzuki K Poulose To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, marc.zyngier@arm.com, cdall@kernel.org, eric.auger@redhat.com, julien.grall@arm.com, will.deacon@arm.com, catalin.marinas@arm.com, punit.agrawal@arm.com, qemu-devel@nongnu.org, Suzuki K Poulose Subject: [PATCH v3 19/20] kvm: arm64: Allow IPA size supported by the system Date: Fri, 29 Jun 2018 12:15:39 +0100 Message-Id: <1530270944-11351-20-git-send-email-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1530270944-11351-1-git-send-email-suzuki.poulose@arm.com> References: <1530270944-11351-1-git-send-email-suzuki.poulose@arm.com> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP So far we have restricted the IPA size of the VM to the default value (40bits). Now that we can manage the IPA size per VM and support dynamic stage2 page tables, allow VMs to have larger IPA. This is done by setting the IPA limit to the one supported by the hardware and kernel. This patch also moves the check for the default IPA size support to kvm_get_ipa_limit(). Since the stage2 page table code is dependent on the stage1 page table, we always ensure that : Number of Levels at Stage1 >= Number of Levels at Stage2 So we limit the IPA to make sure that the above condition is satisfied. This will affect the following combinations of VA_BITS and IPA for different page sizes. 39bit VA, 4K - IPA > 43 (Upto 48) 36bit VA, 16K - IPA > 40 (Upto 48) 42bit VA, 64K - IPA > 46 (Upto 52) Supporting the above combinations need independent stage2 page table manipulation code, which would need substantial changes. We could purse the solution independently and switch the page table code once we have it ready. Cc: Catalin Marinas Cc: Marc Zyngier Cc: Christoffer Dall Signed-off-by: Suzuki K Poulose --- Changes since V2: - Restrict the IPA size to limit the number of page table levels in stage2 to that of stage1 or less. --- arch/arm64/include/asm/kvm_host.h | 6 ------ arch/arm64/include/asm/kvm_mmu.h | 37 ++++++++++++++++++++++++++++++++++++- 2 files changed, 36 insertions(+), 7 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 9a15860..e858e49 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -452,13 +452,7 @@ int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu, static inline void __cpu_init_stage2(void) { - u32 ps; - kvm_call_hyp(__init_stage2_translation); - /* Sanity check for minimum IPA size support */ - ps = id_aa64mmfr0_parange_to_phys_shift(read_sysreg(id_aa64mmfr0_el1) & 0x7); - WARN_ONCE(ps < 40, - "PARange is %d bits, unsupported configuration!", ps); } /* Guest/host FPSIMD coordination helpers */ diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index a291cdc..d38f395 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -547,7 +547,42 @@ static inline void *stage2_alloc_pgd(struct kvm *kvm) static inline u32 kvm_get_ipa_limit(void) { - return KVM_PHYS_SHIFT; + unsigned int ipa_max, va_max, parange; + + parange = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1) & 0x7; + ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange); + + /* Raise the limit to the default size for backward compatibility */ + if (ipa_max < KVM_PHYS_SHIFT) { + WARN_ONCE(1, + "PARange is %d bits, unsupported configuration!", + ipa_max); + ipa_max = KVM_PHYS_SHIFT; + } + + /* Clamp it to the PA size supported by the kernel */ + ipa_max = (ipa_max > PHYS_MASK_SHIFT) ? PHYS_MASK_SHIFT : ipa_max; + /* + * Since our stage2 table is dependent on the stage1 page table code, + * we must always honor the following condition: + * + * Number of levels in Stage1 >= Number of levels in Stage2. + * + * So clamp the ipa limit further down to limit the number of levels. + * Since we can concatenate upto 16 tables at entry level, we could + * go upto 4bits above the maximum VA addressible with the current + * number of levels. + */ + va_max = PGDIR_SHIFT + PAGE_SHIFT - 3; + va_max += 4; + + if (va_max < ipa_max) { + kvm_info("Limiting IPA limit to %dbytes due to host VA bits limitation\n", + va_max); + ipa_max = va_max; + } + + return ipa_max; } static inline void kvm_config_stage2(struct kvm *kvm, u32 ipa_shift)