From patchwork Mon Jul 26 15:35:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 12399983 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=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 AF631C4320E for ; Mon, 26 Jul 2021 15:36:05 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4B6C160F59 for ; Mon, 26 Jul 2021 15:36:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 4B6C160F59 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id F0A8F8D0001; Mon, 26 Jul 2021 11:36:00 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D805B8D0006; Mon, 26 Jul 2021 11:36:00 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9FF448D0009; Mon, 26 Jul 2021 11:36:00 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0236.hostedemail.com [216.40.44.236]) by kanga.kvack.org (Postfix) with ESMTP id 659658D0005 for ; Mon, 26 Jul 2021 11:36:00 -0400 (EDT) Received: from smtpin12.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 14A4E1803EB5D for ; Mon, 26 Jul 2021 15:36:00 +0000 (UTC) X-FDA: 78405139680.12.7FC43A1 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf23.hostedemail.com (Postfix) with ESMTP id BDDA590000AF for ; Mon, 26 Jul 2021 15:35:59 +0000 (UTC) Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2322E60F22; Mon, 26 Jul 2021 15:35:58 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1m82e4-001511-HB; Mon, 26 Jul 2021 16:35:56 +0100 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-mm@kvack.org Cc: Sean Christopherson , Matthew Wilcox , Paolo Bonzini , Will Deacon , Quentin Perret , James Morse , Suzuki K Poulose , Alexandru Elisei , kernel-team@android.com Subject: [PATCH v2 3/6] KVM: arm64: Avoid mapping size adjustment on permission fault Date: Mon, 26 Jul 2021 16:35:49 +0100 Message-Id: <20210726153552.1535838-4-maz@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210726153552.1535838-1-maz@kernel.org> References: <20210726153552.1535838-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-mm@kvack.org, seanjc@google.com, willy@infradead.org, pbonzini@redhat.com, will@kernel.org, qperret@google.com, james.morse@arm.com, suzuki.poulose@arm.com, alexandru.elisei@arm.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: BDDA590000AF Authentication-Results: imf23.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf23.hostedemail.com: domain of maz@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=maz@kernel.org X-Stat-Signature: p7mrhg6ok5w36h9hwa4mzh1fz94gq6uw X-HE-Tag: 1627313759-944528 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Since we only support PMD-sized mappings for THP, getting a permission fault on a level that results in a mapping being larger than PAGE_SIZE is a sure indication that we have already upgraded our mapping to a PMD. In this case, there is no need to try and parse userspace page tables, as the fault information already tells us everything. Signed-off-by: Marc Zyngier Reviewed-by: Alexandru Elisei --- arch/arm64/kvm/mmu.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 0adc1617c557..ebb28dd4f2c9 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1076,9 +1076,14 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, * If we are not forced to use page mapping, check if we are * backed by a THP and thus use block mapping if possible. */ - if (vma_pagesize == PAGE_SIZE && !(force_pte || device)) - vma_pagesize = transparent_hugepage_adjust(kvm, memslot, hva, - &pfn, &fault_ipa); + if (vma_pagesize == PAGE_SIZE && !(force_pte || device)) { + if (fault_status == FSC_PERM && fault_granule > PAGE_SIZE) + vma_pagesize = fault_granule; + else + vma_pagesize = transparent_hugepage_adjust(kvm, memslot, + hva, &pfn, + &fault_ipa); + } if (fault_status != FSC_PERM && !device && kvm_has_mte(kvm)) { /* Check the VMM hasn't introduced a new VM_SHARED VMA */