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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 3DDA5C433E0 for ; Tue, 2 Feb 2021 19:01:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 01BA064F5C for ; Tue, 2 Feb 2021 19:01:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237971AbhBBTA4 (ORCPT ); Tue, 2 Feb 2021 14:00:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57332 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239223AbhBBS6d (ORCPT ); Tue, 2 Feb 2021 13:58:33 -0500 Received: from mail-qk1-x74a.google.com (mail-qk1-x74a.google.com [IPv6:2607:f8b0:4864:20::74a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99F8AC061797 for ; Tue, 2 Feb 2021 10:57:46 -0800 (PST) Received: by mail-qk1-x74a.google.com with SMTP id a75so18156120qkg.16 for ; Tue, 02 Feb 2021 10:57:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=KTYEyXIgb4wI42K1yBcuqU69rlausMxtU1GwO2JJSfc=; b=A3SMO1A6jAqBUExSNWmRam6ysZiwsIlC52mBxT2bopExdqHIBugBrv/ileXZbdnRGF i8cVgOJh+zPcodoOUyleOTeF3fMbp4DaOIUDSujm6e6/7JmPxeQlrgtKDMigIhPBFzjW Xqiqa9WEoZ2UW+mP6GwHpblG/H2H8weZzseRVsKfn/YV7BCWl2E+gvJ1+3P7KBd7jGGp LnzaAVttOqPI9eBilD+UWW9acrjfAvbtPMLs/AaAe8Zff4CCewn7UMSyDnlipvlgHexG MDSPtzb/nEzSvA+2X8UUqlK54rdhJ9boWVXOg2MqNj8zbD0QK9BteYRh3RwsBw0UWm5Z 60Jw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=KTYEyXIgb4wI42K1yBcuqU69rlausMxtU1GwO2JJSfc=; b=Q8mW/DXSCuBc6jOoW4Txvw/MPqaxzAgY0G9/9jCV6IwD4RQLofB8DqD5D/Kg4V314Z OQtm4tZp30rbMeaIShYqmQ/orpFEJoj6A6VTo09O98pyF8hMK9GpZnwPIybZRF+5XJu7 D13SuqL0c+5ESBMOcJ4Uzk77qq9SxrwVwgq2x133DITH0wf2ZAPAMjkqQVQQVhCxJTAA G0KuRXXLy8kHy5r3vmemRaKSA9a5NJ5Uw/skQrUnLy2lks6dyvSQ08fYYyq2sRorK6Z/ VPpPjMbDq9dY1qCVdh/baTYwd5IPtB8p1wa8Vu1apBXi+IMBH1i2gWOXyobvC5ddrYIp x6+A== X-Gm-Message-State: AOAM533qzzs1mKk+PHA7B35ci96aZFOZ8s9Xaosuuz/7H2j8VGwpgiKv UqraQWDcH4ZYABwiidZl3anlSNdCLRUN86/taDJNm3POYq8EiRl4/GouupRBlm4e/fONzNv7+1m di2/otp2iOpB8JItgKxrjLtmsr3aneRESAW3t6tf7pFmaldVIBQd+YKJtKZRJupbZY5I0BzQl X-Google-Smtp-Source: ABdhPJw35iQ1myHf6nwzdvwrNMRryl3/GMsxE12DKFd8FH4ic90uHjpGrPkdi51usxmn3uQAKzCJ0aULv8k0 Sender: "bgardon via sendgmr" X-Received: from bgardon.sea.corp.google.com ([2620:15c:100:202:9090:561:5a98:6d47]) (user=bgardon job=sendgmr) by 2002:ad4:4f41:: with SMTP id eu1mr21827353qvb.34.1612292265673; Tue, 02 Feb 2021 10:57:45 -0800 (PST) Date: Tue, 2 Feb 2021 10:57:10 -0800 In-Reply-To: <20210202185734.1680553-1-bgardon@google.com> Message-Id: <20210202185734.1680553-5-bgardon@google.com> Mime-Version: 1.0 References: <20210202185734.1680553-1-bgardon@google.com> X-Mailer: git-send-email 2.30.0.365.g02bc693789-goog Subject: [PATCH v2 04/28] KVM: x86/mmu: Don't redundantly clear TDP MMU pt memory From: Ben Gardon To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini , Peter Xu , Sean Christopherson , Peter Shier , Peter Feiner , Junaid Shahid , Jim Mattson , Yulei Zhang , Wanpeng Li , Vitaly Kuznetsov , Xiao Guangrong , Ben Gardon Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The KVM MMU caches already guarantee that shadow page table memory will be zeroed, so there is no reason to re-zero the page in the TDP MMU page fault handler. No functional change intended. Reviewed-by: Peter Feiner Reviewed-by: Sean Christopherson Acked-by: Paolo Bonzini Signed-off-by: Ben Gardon --- arch/x86/kvm/mmu/tdp_mmu.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index b83a6a3ad29c..3828c0e83466 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -655,7 +655,6 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, sp = alloc_tdp_mmu_page(vcpu, iter.gfn, iter.level); list_add(&sp->link, &vcpu->kvm->arch.tdp_mmu_pages); child_pt = sp->spt; - clear_page(child_pt); new_spte = make_nonleaf_spte(child_pt, !shadow_accessed_mask); -- 2.30.0.365.g02bc693789-goog