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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 BE2ADC282DD for ; Wed, 8 Jan 2020 20:27:16 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 7DC3A20643 for ; Wed, 8 Jan 2020 20:27:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7DC3A20643 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 2B1D54B142; Wed, 8 Jan 2020 15:27:16 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id JwcG67DZgWAF; Wed, 8 Jan 2020 15:27:15 -0500 (EST) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 86B474B16E; Wed, 8 Jan 2020 15:27:11 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id BBF1A4B146 for ; Wed, 8 Jan 2020 15:27:08 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3cecrvIZFyhe for ; Wed, 8 Jan 2020 15:27:07 -0500 (EST) Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id AE2B44B13D for ; Wed, 8 Jan 2020 15:27:07 -0500 (EST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Jan 2020 12:27:06 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,411,1571727600"; d="scan'208";a="211658380" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.202]) by orsmga007.jf.intel.com with ESMTP; 08 Jan 2020 12:27:06 -0800 From: Sean Christopherson To: Paolo Bonzini Subject: [PATCH 08/14] KVM: x86/mmu: Drop level optimization from fast_page_fault() Date: Wed, 8 Jan 2020 12:24:42 -0800 Message-Id: <20200108202448.9669-9-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200108202448.9669-1-sean.j.christopherson@intel.com> References: <20200108202448.9669-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Cc: Wanpeng Li , kvm@vger.kernel.org, David Hildenbrand , Peter Zijlstra , Dave Hansen , Paul Mackerras , linux-mm@kvack.org, kvmarm@lists.cs.columbia.edu, Dave Jiang , linux-nvdimm , Marc Zyngier , Joerg Roedel , syzbot+c9d1fb51ac9d0d10c39d@syzkaller.appspotmail.com, Barret Rhoden , kvm-ppc@vger.kernel.org, Liran Alon , Andy Lutomirski , Dan Williams , Andrew Morton , linux-arm-kernel@lists.infradead.org, Jim Mattson , linux-kernel@vger.kernel.org, Sean Christopherson , Jason Zeng , Vitaly Kuznetsov X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu Remove fast_page_fault()'s optimization to stop the shadow walk if the iterator level drops below the intended map level. The intended map level is only acccurate for HugeTLB mappings (THP mappings are detected after fast_page_fault()), i.e. it's not required for correctness, and a future patch will also move HugeTLB mapping detection to after fast_page_fault(). Signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 4bd7f745b56d..7d78d1d996ed 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -3593,7 +3593,7 @@ static bool is_access_allowed(u32 fault_err_code, u64 spte) * - true: let the vcpu to access on the same address again. * - false: let the real page fault path to fix it. */ -static bool fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, int level, +static bool fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u32 error_code) { struct kvm_shadow_walk_iterator iterator; @@ -3611,8 +3611,7 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, int level, u64 new_spte; for_each_shadow_entry_lockless(vcpu, cr2_or_gpa, iterator, spte) - if (!is_shadow_present_pte(spte) || - iterator.level < level) + if (!is_shadow_present_pte(spte)) break; sp = page_header(__pa(iterator.sptep)); @@ -4223,7 +4222,7 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, if (level > PT_PAGE_TABLE_LEVEL) gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1); - if (fast_page_fault(vcpu, gpa, level, error_code)) + if (fast_page_fault(vcpu, gpa, error_code)) return RET_PF_RETRY; mmu_seq = vcpu->kvm->mmu_notifier_seq; -- 2.24.1 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm