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 104B3C433F5 for ; Tue, 29 Mar 2022 22:28:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237114AbiC2WaE (ORCPT ); Tue, 29 Mar 2022 18:30:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37102 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235540AbiC2WaA (ORCPT ); Tue, 29 Mar 2022 18:30:00 -0400 Received: from mail-pl1-x62a.google.com (mail-pl1-x62a.google.com [IPv6:2607:f8b0:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 061A46333 for ; Tue, 29 Mar 2022 15:28:16 -0700 (PDT) Received: by mail-pl1-x62a.google.com with SMTP id a16so1974277plh.13 for ; Tue, 29 Mar 2022 15:28:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=vjcQWfLhbG0uWlWmdRXNd421Er7E9z2hWWjFUh0KLac=; b=OGLO94A5JWnv/1HgSvDkWtlZJ3KU0e1HVGPbLk1//DxgmJp5CzBFGqzrXpYKOet3CI MRdJXVjjM/YvN6nR0cdWOtpHtnrIaBS8AGoqWHODJ1D3gmNv7gKi/29MLo/3pNmq8BXr B1Is/E6Y3bdgDcyCcoaVmdiPfJgUdpKWNMbxpMxQlSHg1/wrvj1TvGYhWtfUV0Sxrbw2 LPm/I0nN8vCvFXQf+AVGIqSE/SU8aLItoAQFJ626eiC4xjbHLmSNGjuk2t0eQYd+xAcx dsmBEMPa3ZexRfAacNlqhWctL1dkGfh6QS9hihyJt2JJNu/Yhblhckoiyax1sVGHsUJG Mh9w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=vjcQWfLhbG0uWlWmdRXNd421Er7E9z2hWWjFUh0KLac=; b=1wsUk9F8agMzFGS+PV26ljd5enVnKRNvhkvxwj2Q4Fk5FG6AeaRespNnH7SUlniDix FAM7n3Jikm/Pa5J0qpjdmyxbV0pIR3XGf7cXu2z3MHxAGjcQWC3QjDb/I06RRrEyhr9S Lh92+EWcj4Nlv9ZKX2RH4rEcuPBs1A4LwMdg/t98xxsb4mEeRQtxGu0z9ujrFGAPdtXO VpH8SAcyjPAP0Tb1a/3T1gLkjDgDZQ1IFZX2ktkbl6aRTJRD7DtsRy/8xiWBDefvC/0S BnnR9Gwo9McVWKH0JXz2t8hdjd1gYvoupiDaG57zjourWGAEunQ7Qp2cCIhsLEglSGFJ Ujcg== X-Gm-Message-State: AOAM533xo1oO5i2g17ZuIcmOaWS/YwCeR9/ceuX1D4I3Wb9pECdlj2Ha HZMSGT1a8yUF25R0Bb1KZxusDg== X-Google-Smtp-Source: ABdhPJzgAPJDsue3uchTl3K7kEiko/T1kxeOR+TSgffxAJ/PrZ1l3QiItWqukpVDfkpMLPfIyYOVrQ== X-Received: by 2002:a17:902:e2c3:b0:155:c75c:335d with SMTP id l3-20020a170902e2c300b00155c75c335dmr27420796plc.33.1648592895356; Tue, 29 Mar 2022 15:28:15 -0700 (PDT) Received: from google.com (157.214.185.35.bc.googleusercontent.com. [35.185.214.157]) by smtp.gmail.com with ESMTPSA id k62-20020a17090a4cc400b001c7ea7f487asm3868557pjh.39.2022.03.29.15.28.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 29 Mar 2022 15:28:14 -0700 (PDT) Date: Tue, 29 Mar 2022 22:28:10 +0000 From: Sean Christopherson To: Mingwei Zhang Cc: Paolo Bonzini , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Ben Gardon , David Matlack , Jing Zhang , Peter Xu , Yosry Ahmed Subject: Re: [PATCH v2 3/4] KVM: x86/mmu: explicitly check nx_hugepage in disallowed_hugepage_adjust() Message-ID: References: <20220323184915.1335049-1-mizhang@google.com> <20220323184915.1335049-5-mizhang@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 29, 2022, Sean Christopherson wrote: > > Fixes: b8e8c8303ff2 ("kvm: mmu: ITLB_MULTIHIT mitigation") > > Cc: stable@vger.kernel.org > > I vote to keep the Fixes tag, but drop the Cc: stable@ and NAK any MANUALSEL/AUTOSEL > for backporting this to stable trees. Yes, it's a bug, but the NX huge page zapping > kthread will (eventually) reclaim the lost performance. On the flip side, if there's > an edge case we mess up (see below), then we've introduced a far worse bug. Doh, that's wrong. The whole problem is that these pages aren't on the NX list... I think I'd still vote to not send this to stable, but it's a weak vote.