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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53605C433FE for ; Mon, 21 Mar 2022 13:59:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348547AbiCUOAj (ORCPT ); Mon, 21 Mar 2022 10:00:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46274 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348789AbiCUN6R (ORCPT ); Mon, 21 Mar 2022 09:58:17 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF9BE174BAA; Mon, 21 Mar 2022 06:56:30 -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 ams.source.kernel.org (Postfix) with ESMTPS id 909FCB81598; Mon, 21 Mar 2022 13:56:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D02C2C340E8; Mon, 21 Mar 2022 13:56:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1647870989; bh=LaU3vxjYoNBfirEwBHnRQFnFf8IXd9iO7q8zwVVXGiQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=js0+YGF7ps8RUY4QiGXDTx+dqNLjHVZtHFrTslvDeUjWV6ZCxmAYd0kOIUKBNC3IG ERWXonu6dxuuS/mwnnBcjylXxyq3UfzsewIVAo6kdId0UnC9813xxxrMrNg8D/0x3E XGa3zIExo7dYQdStFBdy5F6LTNLjZG5KjFXLhmdQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , "Russell King (Oracle)" , Catalin Marinas , James Morse Subject: [PATCH 4.19 42/57] KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated Date: Mon, 21 Mar 2022 14:52:23 +0100 Message-Id: <20220321133223.213391721@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220321133221.984120927@linuxfoundation.org> References: <20220321133221.984120927@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: James Morse commit a5905d6af492ee6a4a2205f0d550b3f931b03d03 upstream. KVM allows the guest to discover whether the ARCH_WORKAROUND SMCCC are implemented, and to preserve that state during migration through its firmware register interface. Add the necessary boiler plate for SMCCC_ARCH_WORKAROUND_3. Reviewed-by: Russell King (Oracle) Reviewed-by: Catalin Marinas [ kvm code moved to virt/kvm/arm, removed fw regs ABI. Added 32bit stub ] Signed-off-by: James Morse Signed-off-by: Greg Kroah-Hartman --- arch/arm/include/asm/kvm_host.h | 7 +++++++ arch/arm64/include/asm/kvm_host.h | 5 +++++ virt/kvm/arm/psci.c | 12 ++++++++++++ 3 files changed, 24 insertions(+) --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -26,6 +26,7 @@ #include #include #include +#include #include #define __KVM_HAVE_ARCH_INTC_INITIALIZED @@ -367,4 +368,10 @@ void kvm_arch_free_vm(struct kvm *kvm); #define kvm_arm_vcpu_loaded(vcpu) (false) +static inline int kvm_arm_get_spectre_bhb_state(void) +{ + /* 32bit guests don't need firmware for this */ + return SPECTRE_VULNERABLE; /* aka SMCCC_RET_NOT_SUPPORTED */ +} + #endif /* __ARM_KVM_HOST_H__ */ --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -542,4 +542,9 @@ void kvm_arch_free_vm(struct kvm *kvm); #define kvm_arm_vcpu_loaded(vcpu) ((vcpu)->arch.sysregs_loaded_on_cpu) +static inline enum mitigation_state kvm_arm_get_spectre_bhb_state(void) +{ + return arm64_get_spectre_bhb_state(); +} + #endif /* __ARM64_KVM_HOST_H__ */ --- a/virt/kvm/arm/psci.c +++ b/virt/kvm/arm/psci.c @@ -429,6 +429,18 @@ int kvm_hvc_call_handler(struct kvm_vcpu break; } break; + case ARM_SMCCC_ARCH_WORKAROUND_3: + switch (kvm_arm_get_spectre_bhb_state()) { + case SPECTRE_VULNERABLE: + break; + case SPECTRE_MITIGATED: + val = SMCCC_RET_SUCCESS; + break; + case SPECTRE_UNAFFECTED: + val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED; + break; + } + break; } break; default: