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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5296C55184 for ; Tue, 21 Apr 2020 14:29:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C665B206F4 for ; Tue, 21 Apr 2020 14:29:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587479379; bh=Z3SAyJ+K8U4voELx90j49yg6ENkNXXLr7yM/HxwV9GE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=kodVS8UsZT6wIKczfTzIyL/oOXDXe1xuORLlSB2BzJRHSfhN8RBVY8UO22+gmArCi xJ7WxkUp18m1MUUqfZOXgzLjrQHVjO/blPdP0y/id9UKRBkNh6bls1dvZdxXr7mrDy JfuNJuV6aigrtXvFQv4HLyWV85uG69Eoozq80wEI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729078AbgDUO3i (ORCPT ); Tue, 21 Apr 2020 10:29:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:42234 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729013AbgDUO3g (ORCPT ); Tue, 21 Apr 2020 10:29:36 -0400 Received: from localhost.localdomain (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 42D182071E; Tue, 21 Apr 2020 14:29:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587479375; bh=Z3SAyJ+K8U4voELx90j49yg6ENkNXXLr7yM/HxwV9GE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=liFNkhlrc/hJrKIJbUUoN7Ue1AtOwo1n5VfyN6dUy+hT75/hsnHyQi2py2EUoX8sG zdRRSc+PTeJ6DHr7lSuwv++G2yFF4LqAeYUBNVj9H5oRqFZRg18PIEAqZp3QXMx5FG xmPfwT8kZfT53ePitklgmBeg8gfHlbsZ+iLxEVCY= From: Will Deacon To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Cc: linux-kernel@vger.kernel.org, Will Deacon , Suzuki K Poulose , Mark Rutland , Marc Zyngier , Anshuman Khandual , Catalin Marinas , Sai Prakash Ranjan , Doug Anderson , kernel-team@android.com Subject: [PATCH v2 3/8] arm64: cpufeature: Add CPU capability for AArch32 EL1 support Date: Tue, 21 Apr 2020 15:29:17 +0100 Message-Id: <20200421142922.18950-4-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200421142922.18950-1-will@kernel.org> References: <20200421142922.18950-1-will@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Although we emit a "SANITY CHECK" warning and taint the kernel if we detect a CPU mismatch for AArch32 support at EL1, we still online the CPU with disastrous consequences for any running 32-bit VMs. Introduce a capability for AArch32 support at EL1 so that late onlining of incompatible CPUs is forbidden. Acked-by: Marc Zyngier Reviewed-by: Suzuki K Poulose Tested-by: Sai Prakash Ranjan Signed-off-by: Will Deacon --- arch/arm64/include/asm/cpucaps.h | 3 ++- arch/arm64/include/asm/sysreg.h | 1 + arch/arm64/kernel/cpufeature.c | 12 ++++++++++++ arch/arm64/kvm/reset.c | 12 ++---------- 4 files changed, 17 insertions(+), 11 deletions(-) diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index 8eb5a088ae65..c54c674e6c21 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -61,7 +61,8 @@ #define ARM64_HAS_AMU_EXTN 51 #define ARM64_HAS_ADDRESS_AUTH 52 #define ARM64_HAS_GENERIC_AUTH 53 +#define ARM64_HAS_32BIT_EL1 54 -#define ARM64_NCAPS 54 +#define ARM64_NCAPS 55 #endif /* __ASM_CPUCAPS_H */ diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index d7181972d28d..c4e896bf77f3 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -655,6 +655,7 @@ #define ID_AA64PFR0_ASIMD_NI 0xf #define ID_AA64PFR0_ASIMD_SUPPORTED 0x0 #define ID_AA64PFR0_EL1_64BIT_ONLY 0x1 +#define ID_AA64PFR0_EL1_32BIT_64BIT 0x2 #define ID_AA64PFR0_EL0_64BIT_ONLY 0x1 #define ID_AA64PFR0_EL0_32BIT_64BIT 0x2 diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index b143f8bc6c52..838fe5cc8d7e 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1535,6 +1535,18 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .field_pos = ID_AA64PFR0_EL0_SHIFT, .min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT, }, +#ifdef CONFIG_KVM + { + .desc = "32-bit EL1 Support", + .capability = ARM64_HAS_32BIT_EL1, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, + .matches = has_cpuid_feature, + .sys_reg = SYS_ID_AA64PFR0_EL1, + .sign = FTR_UNSIGNED, + .field_pos = ID_AA64PFR0_EL1_SHIFT, + .min_field_value = ID_AA64PFR0_EL1_32BIT_64BIT, + }, +#endif { .desc = "Kernel page table isolation (KPTI)", .capability = ARM64_UNMAP_KERNEL_AT_EL0, diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index 30b7ea680f66..102e5c4e01a0 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -46,14 +46,6 @@ static const struct kvm_regs default_regs_reset32 = { PSR_AA32_I_BIT | PSR_AA32_F_BIT), }; -static bool cpu_has_32bit_el1(void) -{ - u64 pfr0; - - pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); - return !!(pfr0 & 0x20); -} - /** * kvm_arch_vm_ioctl_check_extension * @@ -66,7 +58,7 @@ int kvm_arch_vm_ioctl_check_extension(struct kvm *kvm, long ext) switch (ext) { case KVM_CAP_ARM_EL1_32BIT: - r = cpu_has_32bit_el1(); + r = cpus_have_const_cap(ARM64_HAS_32BIT_EL1); break; case KVM_CAP_GUEST_DEBUG_HW_BPS: r = get_num_brps(); @@ -288,7 +280,7 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) switch (vcpu->arch.target) { default: if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) { - if (!cpu_has_32bit_el1()) + if (!cpus_have_const_cap(ARM64_HAS_32BIT_EL1)) goto out; cpu_reset = &default_regs_reset32; } else { -- 2.26.1.301.g55bc3eb7cb9-goog