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=-16.6 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, 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 76D58C433E0 for ; Fri, 19 Mar 2021 10:02:55 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id DE2FB64F1F for ; Fri, 19 Mar 2021 10:02:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DE2FB64F1F Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.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 8C1D94B6A2; Fri, 19 Mar 2021 06:02:54 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@google.com 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 uSnOvw+9IBYf; Fri, 19 Mar 2021 06:02:53 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 596054B723; Fri, 19 Mar 2021 06:02:53 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 79A294B72A for ; Fri, 19 Mar 2021 06:02:52 -0400 (EDT) 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 HHO02XRuk3Ti for ; Fri, 19 Mar 2021 06:02:51 -0400 (EDT) Received: from mail-wr1-f73.google.com (mail-wr1-f73.google.com [209.85.221.73]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 139CF4B682 for ; Fri, 19 Mar 2021 06:02:51 -0400 (EDT) Received: by mail-wr1-f73.google.com with SMTP id h5so21519887wrr.17 for ; Fri, 19 Mar 2021 03:02:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=uBuSDgADlVyxIdI3BmsAIPCPmlM7WqeZ0Oeo6QVFLts=; b=qCWraLZ0Tszd8AH74n5bMJc2ZNxpli+5BtX1Qu0TYtfObzVU7M02pQnddE7gvCf0iN pxmN8wb8E3OkHG0yFhoGSKXtXucoyZgOukVOd9KIzkfTZ/qis1gqdYkYBY6SgONRydNY KY5mRl/bU+IaXK3gVCVIou3kiMKprdEqZ7Fs1tKl1gCFYmPlEuuIQYwaYZS+QSHTyqNY 47eTUx6l0G5XKkzF68I0V5R/05uQim6YGk9NHHdWAPWlBjSiZ4pqQy1/gCTdPSfuywh9 Pg0WV+45hM8j8NIgdxeyB2hzRuAj3f9jXw1V3wXA8TEq7M0aKy6iE4YGWe1j2bPyM4Xy etHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=uBuSDgADlVyxIdI3BmsAIPCPmlM7WqeZ0Oeo6QVFLts=; b=lgMBmlciyl21285evoJ1PBimDFCL2zsW2zLIhO48VfcuhEFQ4kpAGkPlKSZacsLAN4 JglAvHohEg81ANuH2HL+kd3Nef2JhEwl9wGfvZiw3NUyGlepo8u32Sm16j8LvQGIRmzZ SlH9Oy+HIn++9XV2+S1UdX62iQ/5m/qBLYP/gf2yMw0oZ5f5cddZRSRrvGu13Ixu3zpX NuUaGEmrMA2A201Vx2P1wlKmNSJdsIepcV2HczS7Hkq3jyKOfQ5+YdsS00i1pd/3LXLw +pl/NT/EncIxzZEtWOUYGQ5yR3m50F/TyHEUSTtr5EwB9gl2qCqTyKSZ1UjWeL4Ue/+P 6LOQ== X-Gm-Message-State: AOAM532FnZHLKc5Mb6Hhr9Nl+cKyeLi2cU4dYY/yjPFapUOT5kDpyD1L BApoPKWFZwMCRUQ389JX8HpmQa05tT6x X-Google-Smtp-Source: ABdhPJy7gzoGDveYEOxbSnLDlDyWEZkPizO1OQME7oNr7V9YSTxgGFBprzpO+9yJFS/BuMsKlUSbA1VxNmbB X-Received: from r2d2-qp.c.googlers.com ([fda3:e722:ac3:10:28:9cb1:c0a8:1652]) (user=qperret job=sendgmr) by 2002:a05:600c:4ed1:: with SMTP id g17mr2965040wmq.67.1616148170085; Fri, 19 Mar 2021 03:02:50 -0700 (PDT) Date: Fri, 19 Mar 2021 10:01:36 +0000 In-Reply-To: <20210319100146.1149909-1-qperret@google.com> Message-Id: <20210319100146.1149909-29-qperret@google.com> Mime-Version: 1.0 References: <20210319100146.1149909-1-qperret@google.com> X-Mailer: git-send-email 2.31.0.rc2.261.g7f71774620-goog Subject: [PATCH v6 28/38] KVM: arm64: Always zero invalid PTEs From: Quentin Perret To: catalin.marinas@arm.com, will@kernel.org, maz@kernel.org, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com Cc: android-kvm@google.com, seanjc@google.com, mate.toth-pal@arm.com, linux-kernel@vger.kernel.org, robh+dt@kernel.org, tabba@google.com, kernel-team@android.com, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org 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 kvm_set_invalid_pte() currently only clears bit 0 from a PTE because stage2_map_walk_table_post() needs to be able to follow the anchor. In preparation for re-using bits 63-01 from invalid PTEs, make sure to zero it entirely by ensuring to cache the anchor's child upfront. Acked-by: Will Deacon Suggested-by: Will Deacon Signed-off-by: Quentin Perret --- arch/arm64/kvm/hyp/pgtable.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index 15de1708cfcd..0a674010afb6 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -156,10 +156,9 @@ static kvm_pte_t *kvm_pte_follow(kvm_pte_t pte, struct kvm_pgtable_mm_ops *mm_op return mm_ops->phys_to_virt(kvm_pte_to_phys(pte)); } -static void kvm_set_invalid_pte(kvm_pte_t *ptep) +static void kvm_clear_pte(kvm_pte_t *ptep) { - kvm_pte_t pte = *ptep; - WRITE_ONCE(*ptep, pte & ~KVM_PTE_VALID); + WRITE_ONCE(*ptep, 0); } static void kvm_set_table_pte(kvm_pte_t *ptep, kvm_pte_t *childp, @@ -444,6 +443,7 @@ struct stage2_map_data { kvm_pte_t attr; kvm_pte_t *anchor; + kvm_pte_t *childp; struct kvm_s2_mmu *mmu; void *memcache; @@ -533,7 +533,7 @@ static int stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, * There's an existing different valid leaf entry, so perform * break-before-make. */ - kvm_set_invalid_pte(ptep); + kvm_clear_pte(ptep); kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level); mm_ops->put_page(ptep); } @@ -554,7 +554,8 @@ static int stage2_map_walk_table_pre(u64 addr, u64 end, u32 level, if (!kvm_block_mapping_supported(addr, end, data->phys, level)) return 0; - kvm_set_invalid_pte(ptep); + data->childp = kvm_pte_follow(*ptep, data->mm_ops); + kvm_clear_pte(ptep); /* * Invalidate the whole stage-2, as we may have numerous leaf @@ -600,7 +601,7 @@ static int stage2_map_walk_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, * will be mapped lazily. */ if (kvm_pte_valid(pte)) { - kvm_set_invalid_pte(ptep); + kvm_clear_pte(ptep); kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level); mm_ops->put_page(ptep); } @@ -616,19 +617,24 @@ static int stage2_map_walk_table_post(u64 addr, u64 end, u32 level, struct stage2_map_data *data) { struct kvm_pgtable_mm_ops *mm_ops = data->mm_ops; + kvm_pte_t *childp; int ret = 0; if (!data->anchor) return 0; - mm_ops->put_page(kvm_pte_follow(*ptep, mm_ops)); - mm_ops->put_page(ptep); - if (data->anchor == ptep) { + childp = data->childp; data->anchor = NULL; + data->childp = NULL; ret = stage2_map_walk_leaf(addr, end, level, ptep, data); + } else { + childp = kvm_pte_follow(*ptep, mm_ops); } + mm_ops->put_page(childp); + mm_ops->put_page(ptep); + return ret; } @@ -737,7 +743,7 @@ static int stage2_unmap_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, * block entry and rely on the remaining portions being faulted * back lazily. */ - kvm_set_invalid_pte(ptep); + kvm_clear_pte(ptep); kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, mmu, addr, level); mm_ops->put_page(ptep); -- 2.31.0.rc2.261.g7f71774620-goog _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm