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 02EE9C433EF for ; Wed, 1 Dec 2021 17:05:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238178AbhLARIW (ORCPT ); Wed, 1 Dec 2021 12:08:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53730 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351710AbhLARHx (ORCPT ); Wed, 1 Dec 2021 12:07:53 -0500 Received: from mail-wr1-x44a.google.com (mail-wr1-x44a.google.com [IPv6:2a00:1450:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 288ABC06174A for ; Wed, 1 Dec 2021 09:04:31 -0800 (PST) Received: by mail-wr1-x44a.google.com with SMTP id v18-20020a5d5912000000b001815910d2c0so4466814wrd.1 for ; Wed, 01 Dec 2021 09:04:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=9uBUypl+EXPtiyqLggdiPCeBqKTFxHsKtVyJKG8pgmY=; b=Vv1c7CHoktHXpAkMllAbrV9Qh8WJZnyTA3AZU15KbH4HMkRzFi9p8jcrrt9SYvw/vm XiJfozl/oFlTHNfLRWY3HBA3gFa9GG27TT0SAeeuzCVqz8nF3/MFgRTE1JTlFJUP24Ec BzDBGevNwW/zf0YB+zazdFhJ4kiNaPq5iHmleo2R5XUDtGWhB+8awKuhqPooz9Z/mSNG gs4ndbhCyBpRHS3gb21jCowKbTdnE1ozwPsjKll5mD7/DVNd1EvOyQ72bfzphCiSXYhN gFAldNGJnBPpUdYyDkMsuJXxN+63Mq6uHhqZqhCmWw9MzrD9lAxNSXUtKzeOMkHVbfX8 pvlg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=9uBUypl+EXPtiyqLggdiPCeBqKTFxHsKtVyJKG8pgmY=; b=vBJCkKrRDBQOevm9cwBchatgbUGPkOjCxDg5WfhmpTaKe1Pn7kligncJaql7YEOL/K cQiz5iDfk5V8VvlfNk9RJMF67wTDYBiwXKbk3w9WCvEwBVMkQEYaQtf8E2+YO05mQMuw YlnoYHBNOEf3zFWcyWF0UBUMtlj61w0KMlnc+DRO2aRxPs6/0bFY/rFKPez8C++U0IDC ADZMja+zpkFz6vvdxn8oXcHI8DmWO5dQ3q5uVVEk6K1lp+iMIGf5t5bldkU+Nq52eWoc XNx0Mv338sNyg+q81FZRDuMPIsxM9A4qdjXnMkJbvAc13e2T80XHEn/0peufspKOr9Jd 0pVw== X-Gm-Message-State: AOAM530nor2eavXbVxKitikCae5/gjHizzj73Vqg5B6mhilKHaBZzjuw VxPUpnB49hXVRsnvsBm1ck7c9Vx5AL9G X-Google-Smtp-Source: ABdhPJynMlhVluzA+1W+geGVMD660u2IXflLbXQYLj5MfYI1LEe60lA76lE/vavpHK8Z8gHIBVjRNs1KfRK+ X-Received: from luke.lon.corp.google.com ([2a00:79e0:d:210:1cab:1a20:2ef1:ddde]) (user=qperret job=sendgmr) by 2002:a05:600c:1d1b:: with SMTP id l27mr113174wms.1.1638378269441; Wed, 01 Dec 2021 09:04:29 -0800 (PST) Date: Wed, 1 Dec 2021 17:03:58 +0000 In-Reply-To: <20211201170411.1561936-1-qperret@google.com> Message-Id: <20211201170411.1561936-5-qperret@google.com> Mime-Version: 1.0 References: <20211201170411.1561936-1-qperret@google.com> X-Mailer: git-send-email 2.34.0.rc2.393.gf8c9666880-goog Subject: [PATCH v3 04/15] KVM: arm64: Fixup hyp stage-1 refcount From: Quentin Perret To: Marc Zyngier , James Morse , Alexandru Elisei , Suzuki K Poulose , Catalin Marinas , Will Deacon Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, kernel-team@android.com Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In nVHE-protected mode, the hyp stage-1 page-table refcount is broken due to the lack of refcount support in the early allocator. Fix-up the refcount in the finalize walker, once the 'hyp_vmemmap' is up and running. Signed-off-by: Quentin Perret --- arch/arm64/kvm/hyp/nvhe/setup.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c index 578f71798c2e..875b5174342f 100644 --- a/arch/arm64/kvm/hyp/nvhe/setup.c +++ b/arch/arm64/kvm/hyp/nvhe/setup.c @@ -165,6 +165,7 @@ static int finalize_host_mappings_walker(u64 addr, u64 end, u32 level, enum kvm_pgtable_walk_flags flag, void * const arg) { + struct kvm_pgtable_mm_ops *mm_ops = arg; enum kvm_pgtable_prot prot; enum pkvm_page_state state; kvm_pte_t pte = *ptep; @@ -173,6 +174,15 @@ static int finalize_host_mappings_walker(u64 addr, u64 end, u32 level, if (!kvm_pte_valid(pte)) return 0; + /* + * Fix-up the refcount for the page-table pages as the early allocator + * was unable to access the hyp_vmemmap and so the buddy allocator has + * initialised the refcount to '1'. + */ + mm_ops->get_page(ptep); + if (flag != KVM_PGTABLE_WALK_LEAF) + return 0; + if (level != (KVM_PGTABLE_MAX_LEVELS - 1)) return -EINVAL; @@ -205,7 +215,8 @@ static int finalize_host_mappings(void) { struct kvm_pgtable_walker walker = { .cb = finalize_host_mappings_walker, - .flags = KVM_PGTABLE_WALK_LEAF, + .flags = KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST, + .arg = pkvm_pgtable.mm_ops, }; int i, ret; @@ -240,10 +251,6 @@ void __noreturn __pkvm_init_finalise(void) if (ret) goto out; - ret = finalize_host_mappings(); - if (ret) - goto out; - pkvm_pgtable_mm_ops = (struct kvm_pgtable_mm_ops) { .zalloc_page = hyp_zalloc_hyp_page, .phys_to_virt = hyp_phys_to_virt, @@ -253,6 +260,10 @@ void __noreturn __pkvm_init_finalise(void) }; pkvm_pgtable.mm_ops = &pkvm_pgtable_mm_ops; + ret = finalize_host_mappings(); + if (ret) + goto out; + out: /* * We tail-called to here from handle___pkvm_init() and will not return, -- 2.34.0.rc2.393.gf8c9666880-goog