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 7F7B3C433FE for ; Wed, 6 Apr 2022 20:18:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234469AbiDFUUR (ORCPT ); Wed, 6 Apr 2022 16:20:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234104AbiDFUTc (ORCPT ); Wed, 6 Apr 2022 16:19:32 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E2E728D2A0; Wed, 6 Apr 2022 11:28:29 -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 01840B824E1; Wed, 6 Apr 2022 18:28:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6B25FC385A3; Wed, 6 Apr 2022 18:28:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649269706; bh=NgqVS5WrlftclBEuSycZ8OoPFaK+Gbw/CFEjdjdLH8w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vzSRhOgddLkSmjECL5R9J+p0qSz5XQWO4+szW0tDNy5yLkli3boBGbfl6OYRQ7rML yNY/nOs8IyBSuOrDXN2cNBKkXZOmFXAwAPPhf6rVXTFa+JQGm0P8hozXo3XeUlrsSx LKjp2QsvaFf1RCxWeyF/CdSzCFvRlnEPK7duwhck= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Russell King (Oracle)" , Catalin Marinas , James Morse Subject: [PATCH 4.9 41/43] KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated Date: Wed, 6 Apr 2022 20:26:50 +0200 Message-Id: <20220406182437.872916215@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220406182436.675069715@linuxfoundation.org> References: <20220406182436.675069715@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: linux-kernel@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 arch/arm/kvm, 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 | 5 +++++ arch/arm/kvm/psci.c | 4 ++++ arch/arm64/include/asm/kvm_host.h | 4 ++++ 3 files changed, 13 insertions(+) --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -349,4 +349,9 @@ static inline int kvm_arm_have_ssbd(void return KVM_SSBD_UNKNOWN; } +static inline bool kvm_arm_spectre_bhb_mitigated(void) +{ + /* 32bit guests don't need firmware for this */ + return false; +} #endif /* __ARM_KVM_HOST_H__ */ --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -431,6 +431,10 @@ int kvm_hvc_call_handler(struct kvm_vcpu break; } break; + case ARM_SMCCC_ARCH_WORKAROUND_3: + if (kvm_arm_spectre_bhb_mitigated()) + val = SMCCC_RET_SUCCESS; + break; } break; default: --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -452,4 +452,8 @@ static inline int kvm_arm_have_ssbd(void } } +static inline bool kvm_arm_spectre_bhb_mitigated(void) +{ + return arm64_get_spectre_bhb_state() == SPECTRE_MITIGATED; +} #endif /* __ARM64_KVM_HOST_H__ */