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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 5F2B1ECE568 for ; Mon, 24 Sep 2018 20:53:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 11B2D2087A for ; Mon, 24 Sep 2018 20:53:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 11B2D2087A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728186AbeIYC5I (ORCPT ); Mon, 24 Sep 2018 22:57:08 -0400 Received: from foss.arm.com ([217.140.101.70]:41860 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728122AbeIYC5H (ORCPT ); Mon, 24 Sep 2018 22:57:07 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 82C017A9; Mon, 24 Sep 2018 13:53:04 -0700 (PDT) Received: from [10.37.9.1] (unknown [10.37.9.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8A9FA3F5B7; Mon, 24 Sep 2018 13:53:02 -0700 (PDT) Subject: Re: [PATCH v7 1/9] KVM: arm/arm64: Ensure only THP is candidate for adjustment To: Punit Agrawal , kvmarm@lists.cs.columbia.edu Cc: marc.zyngier@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Christoffer Dall , stable@vger.kernel.org References: <20180924174552.8387-1-punit.agrawal@arm.com> <20180924174552.8387-2-punit.agrawal@arm.com> From: Suzuki K Poulose Message-ID: <2827f67b-d734-aca5-d790-c350a81f0792@arm.com> Date: Mon, 24 Sep 2018 21:54:02 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180924174552.8387-2-punit.agrawal@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Punit, On 09/24/2018 06:45 PM, Punit Agrawal wrote: > PageTransCompoundMap() returns true for hugetlbfs and THP > hugepages. This behaviour incorrectly leads to stage 2 faults for > unsupported hugepage sizes (e.g., 64K hugepage with 4K pages) to be > treated as THP faults. > > Tighten the check to filter out hugetlbfs pages. This also leads to > consistently mapping all unsupported hugepage sizes as PTE level > entries at stage 2. > > Signed-off-by: Punit Agrawal > Cc: Christoffer Dall > Cc: Marc Zyngier > Cc: Suzuki Poulose > Cc: stable@vger.kernel.org # v4.13+ > --- > virt/kvm/arm/mmu.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c > index 7e477b3cae5b..c23a1b323aad 100644 > --- a/virt/kvm/arm/mmu.c > +++ b/virt/kvm/arm/mmu.c > @@ -1231,8 +1231,14 @@ static bool transparent_hugepage_adjust(kvm_pfn_t *pfnp, phys_addr_t *ipap) > { > kvm_pfn_t pfn = *pfnp; > gfn_t gfn = *ipap >> PAGE_SHIFT; > + struct page *page = pfn_to_page(pfn); > > - if (PageTransCompoundMap(pfn_to_page(pfn))) { > + /* > + * PageTransCompoungMap() returns true for THP and > + * hugetlbfs. Make sure the adjustment is done only for THP > + * pages. > + */ > + if (!PageHuge(page) && PageTransCompoundMap(page)) { Reviewed-by: Suzuki K Poulose