From patchwork Wed Nov 3 06:25:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Reiji Watanabe X-Patchwork-Id: 12600177 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48202C433F5 for ; Wed, 3 Nov 2021 06:28:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 25ED661139 for ; Wed, 3 Nov 2021 06:28:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231952AbhKCGar (ORCPT ); Wed, 3 Nov 2021 02:30:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231913AbhKCGaq (ORCPT ); Wed, 3 Nov 2021 02:30:46 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4A72BC061203 for ; Tue, 2 Nov 2021 23:28:10 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id f92-20020a25a465000000b005bea37bc0baso2781351ybi.5 for ; Tue, 02 Nov 2021 23:28:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=lJ8r9zWPVVKmzZ6XSiFVL9KgUM/7kGO2C8okeqFq7iE=; b=GqPCo2kbDo0gSPnj0m72zxZN00OWSr6pB/bwwtdLgEnl+1CHLDmcJ7wRo2HBZZl1Uw VJGWlUmgdT15yGsf419qc5odq6L42fdhxeD/SceMwaKW+IJIpMb55xdO8oNMVCc+YC4f SPUnMH279dlDVDa4J21/pmG99XYuWQn3g9fblMyc2IXrAu3Kl1c7HVIWeA4HF7BTg1aw C/pdtC0RxeBplDs+nI9HpawzVghMQe8H06V2FUC9lXnZ8wLza/XlMnqDVLCn+a0Jnx0o vVmHmHg7dah9XVqJfLu3d7/Y8oBnftMRWwQ6gtiwA07RE9JlVNSye4iUezXitwJtiuR+ 2AvA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=lJ8r9zWPVVKmzZ6XSiFVL9KgUM/7kGO2C8okeqFq7iE=; b=Cdd6bFYEVuuXnz7E8tecxUVpoaKs64e8BMPHhBkkv4k8/s1B2HmoLKi/m5A/8gWLF2 MEKKKwwQLYH9qi3I8DYvuDwGz+dF1+OdtK7nVmNZYOjYHjkhVN1IVrYViASz8lxJh9PE dMNx8TYQ+vdOyhL0Aznw92HpANGOGJqjlgn5wwkpTFh0abKiYtbAa0ciP4h0ntlVfTZ3 3CC4pjqvISGcLgVeIGMccDumM0/bq9K5Vs0AleqjEIDSabFhzRtoJhwmNayDJW5H0aYs xvjMJVY9fkYboyo1MRsk56ObUGJNPdi8QydNFL7bwfCErkFAnfc1hz+QRRk4sud4MuHV mJYQ== X-Gm-Message-State: AOAM532H8vvUF3Yq+2UWaf7gXXiv5udZT6ToGucjuMaPrCWROwoBckoY NmUScUkaLoQHB1QfrDD+EIVdQ6uk3mI= X-Google-Smtp-Source: ABdhPJxFZGDuaoZmZoSlnGY8V5l2x9kpOlI3wBqVBwlIEIxhhs0O0wxDwHts1tnVSjNnd+MvZ7X1wOjo66k= X-Received: from reiji-vws-sp.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3d59]) (user=reijiw job=sendgmr) by 2002:a25:2395:: with SMTP id j143mr38737153ybj.415.1635920889503; Tue, 02 Nov 2021 23:28:09 -0700 (PDT) Date: Tue, 2 Nov 2021 23:25:01 -0700 In-Reply-To: <20211103062520.1445832-1-reijiw@google.com> Message-Id: <20211103062520.1445832-10-reijiw@google.com> Mime-Version: 1.0 References: <20211103062520.1445832-1-reijiw@google.com> X-Mailer: git-send-email 2.33.1.1089.g2158813163f-goog Subject: [RFC PATCH v2 09/28] KVM: arm64: Make ID_AA64MMFR0_EL1 writable From: Reiji Watanabe To: Marc Zyngier , kvmarm@lists.cs.columbia.edu Cc: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, James Morse , Alexandru Elisei , Suzuki K Poulose , Paolo Bonzini , Will Deacon , Andrew Jones , Peng Liang , Peter Shier , Ricardo Koller , Oliver Upton , Jing Zhang , Raghavendra Rao Anata , Reiji Watanabe Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This patch adds id_reg_info for ID_AA64MMFR0_EL1 to make it writable by userspace. Since ID_AA64MMFR0_EL1 stage 2 granule size fields don't follow the standard ID scheme, we need a special handling to validate those fields. Signed-off-by: Reiji Watanabe --- arch/arm64/kvm/sys_regs.c | 118 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 83b05d37afbd..7c1ac456dc94 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -508,6 +508,113 @@ static int validate_id_aa64isar1_el1(struct kvm_vcpu *vcpu, return 0; } +/* + * Check if the requested stage2 translation granule size indicated in + * @mmfr0 is also indicated in @mmfr0_lim. This function assumes that + * the stage1 granule size indicated in @mmfr0 has been validated already. + */ +static int aa64mmfr0_tgran2_check(int field, u64 mmfr0, u64 mmfr0_lim) +{ + s64 tgran2, lim_tgran2, rtgran1; + int f1; + bool is_signed = true; + + tgran2 = cpuid_feature_extract_unsigned_field(mmfr0, field); + lim_tgran2 = cpuid_feature_extract_unsigned_field(mmfr0_lim, field); + if (tgran2 == lim_tgran2) + return 0; + + if (tgran2 && lim_tgran2) + return (tgran2 > lim_tgran2) ? -E2BIG : 0; + + /* + * Either tgran2 or lim_tgran2 is zero. + * Need stage1 granule size to validate tgran2. + */ + switch (field) { + case ID_AA64MMFR0_TGRAN4_2_SHIFT: + f1 = ID_AA64MMFR0_TGRAN4_SHIFT; + break; + case ID_AA64MMFR0_TGRAN64_2_SHIFT: + f1 = ID_AA64MMFR0_TGRAN64_SHIFT; + break; + case ID_AA64MMFR0_TGRAN16_2_SHIFT: + f1 = ID_AA64MMFR0_TGRAN16_SHIFT; + is_signed = false; + break; + default: + /* Should never happen */ + WARN_ONCE(1, "Unexpected stage2 granule field (%d)\n", field); + return 0; + } + + /* + * If tgran2 == 0 (&& lim_tgran2 != 0), the requested stage2 granule + * size is indicated in the stage1 granule size field of @mmfr0. + * So, validate the stage1 granule size against the stage2 limit + * granule size. + * If lim_tgran2 == 0 (&& tgran2 != 0), the stage2 limit granule size + * is indicated in the stage1 granule size field of @mmfr0_lim. + * So, validate the requested stage2 granule size against the stage1 + * limit granule size. + */ + + /* Get the relevant stage1 granule size to validate tgran2 */ + if (tgran2 == 0) + /* The requested stage1 granule size */ + rtgran1 = cpuid_feature_extract_field(mmfr0, f1, is_signed); + else /* lim_tgran2 == 0 */ + /* The stage1 limit granule size */ + rtgran1 = cpuid_feature_extract_field(mmfr0_lim, f1, is_signed); + + /* + * Adjust the value of rtgran1 to compare with stage2 granule size, + * which indicates: 1: Not supported, 2: Supported, etc. + */ + if (is_signed) + /* For signed, -1: Not supported, 0: Supported, etc. */ + rtgran1 += 0x2; + else + /* For unsigned, 0: Not supported, 1: Supported, etc. */ + rtgran1 += 0x1; + + if ((tgran2 == 0) && (rtgran1 > lim_tgran2)) + /* + * The requested stage1 granule size (== the requested stage2 + * granule size) is larger than the stage2 limit granule size. + */ + return -E2BIG; + else if ((lim_tgran2 == 0) && (tgran2 > rtgran1)) + /* + * The requested stage2 granule size is larger than the stage1 + * limit granulze size (== the stage2 limit granule size). + */ + return -E2BIG; + + return 0; +} + +static int validate_id_aa64mmfr0_el1(struct kvm_vcpu *vcpu, + const struct id_reg_info *id_reg, u64 val) +{ + u64 limit = id_reg->vcpu_limit_val; + int ret; + + ret = aa64mmfr0_tgran2_check(ID_AA64MMFR0_TGRAN4_2_SHIFT, val, limit); + if (ret) + return ret; + + ret = aa64mmfr0_tgran2_check(ID_AA64MMFR0_TGRAN64_2_SHIFT, val, limit); + if (ret) + return ret; + + ret = aa64mmfr0_tgran2_check(ID_AA64MMFR0_TGRAN16_2_SHIFT, val, limit); + if (ret) + return ret; + + return 0; +} + static void init_id_aa64pfr0_el1_info(struct id_reg_info *id_reg) { u64 limit = id_reg->vcpu_limit_val; @@ -601,6 +708,16 @@ static struct id_reg_info id_aa64isar1_el1_info = { .get_reset_val = get_reset_id_aa64isar1_el1, }; +static struct id_reg_info id_aa64mmfr0_el1_info = { + .sys_reg = SYS_ID_AA64MMFR0_EL1, + .ftr_check_types = S_FCT(ID_AA64MMFR0_TGRAN4_SHIFT, FCT_LOWER_SAFE) | + S_FCT(ID_AA64MMFR0_TGRAN64_SHIFT, FCT_LOWER_SAFE) | + U_FCT(ID_AA64MMFR0_TGRAN4_2_SHIFT, FCT_IGNORE) | + U_FCT(ID_AA64MMFR0_TGRAN64_2_SHIFT, FCT_IGNORE) | + U_FCT(ID_AA64MMFR0_TGRAN16_2_SHIFT, FCT_IGNORE), + .validate = validate_id_aa64mmfr0_el1, +}; + /* * An ID register that needs special handling to control the value for the * guest must have its own id_reg_info in id_reg_info_table. @@ -614,6 +731,7 @@ static struct id_reg_info *id_reg_info_table[KVM_ARM_ID_REG_MAX_NUM] = { [IDREG_IDX(SYS_ID_AA64PFR1_EL1)] = &id_aa64pfr1_el1_info, [IDREG_IDX(SYS_ID_AA64ISAR0_EL1)] = &id_aa64isar0_el1_info, [IDREG_IDX(SYS_ID_AA64ISAR1_EL1)] = &id_aa64isar1_el1_info, + [IDREG_IDX(SYS_ID_AA64MMFR0_EL1)] = &id_aa64mmfr0_el1_info, }; static int validate_id_reg(struct kvm_vcpu *vcpu,