From patchwork Tue Apr 26 08:22:08 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 566494 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 46D60C433EF for ; Tue, 26 Apr 2022 09:08:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346535AbiDZJLU (ORCPT ); Tue, 26 Apr 2022 05:11:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346282AbiDZJH3 (ORCPT ); Tue, 26 Apr 2022 05:07:29 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C608CE4BC; Tue, 26 Apr 2022 01:48:45 -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 dfw.source.kernel.org (Postfix) with ESMTPS id DEB2560C42; Tue, 26 Apr 2022 08:48:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CEF8FC385A4; Tue, 26 Apr 2022 08:48:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1650962924; bh=C7K6+dIhO4lVsvHYxez6CLHJhbjfmzvpry9EP/SdI58=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pzeRNfM2nQMjvHFOqOfDyUvLdHo2eUd/C0zXeIoQXXknao/vVJxWWbZExMyHoHh7U 65JsoF14vuqYZlnSSLN+2WbLRpwX0QCsxT7rYpFpOMRSLBGCQMZg8kdjs2nkc1xcXi fjwgKIPcIdarGZ2+xSDMRMFagpnFatV0ZJW71zr0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, stable@vger.kerel.org, Sean Christopherson , Mingwei Zhang , Paolo Bonzini Subject: [PATCH 5.17 133/146] KVM: SVM: Flush when freeing encrypted pages even on SME_COHERENT CPUs Date: Tue, 26 Apr 2022 10:22:08 +0200 Message-Id: <20220426081753.797805653@linuxfoundation.org> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220426081750.051179617@linuxfoundation.org> References: <20220426081750.051179617@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mingwei Zhang commit d45829b351ee6ec5f54dd55e6aca1f44fe239fe6 upstream. Use clflush_cache_range() to flush the confidential memory when SME_COHERENT is supported in AMD CPU. Cache flush is still needed since SME_COHERENT only support cache invalidation at CPU side. All confidential cache lines are still incoherent with DMA devices. Cc: stable@vger.kerel.org Fixes: add5e2f04541 ("KVM: SVM: Add support for the SEV-ES VMSA") Reviewed-by: Sean Christopherson Signed-off-by: Mingwei Zhang Message-Id: <20220421031407.2516575-3-mizhang@google.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/svm/sev.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -2217,11 +2217,14 @@ static void sev_flush_encrypted_page(str unsigned long addr = (unsigned long)va; /* - * If hardware enforced cache coherency for encrypted mappings of the - * same physical page is supported, nothing to do. + * If CPU enforced cache coherency for encrypted mappings of the + * same physical page is supported, use CLFLUSHOPT instead. NOTE: cache + * flush is still needed in order to work properly with DMA devices. */ - if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) + if (boot_cpu_has(X86_FEATURE_SME_COHERENT)) { + clflush_cache_range(va, PAGE_SIZE); return; + } /* * VM Page Flush takes a host virtual address and a guest ASID. Fall