From patchwork Thu Jul 30 15:34:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 11693307 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 27D4614B7 for ; Thu, 30 Jul 2020 15:39:50 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EFB9C2082E for ; Thu, 30 Jul 2020 15:39:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="BaMa8/Jm"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="KB0czXdG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EFB9C2082E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=L/+NjRWs8SzmL9Xa8o+WWp4eYHYAgBg/VnliDR3Uqzo=; b=BaMa8/Jmd1mZuWyELvJCNoEt4 hbpgTql2tKq8q9ACF7O9mtCMHtBS5ODc2ilPJ2J31SlMexS1SvvHkqyZ9GLKiUxdV7bH1VD0Jc2r7 28fIi+SwsfPROV5X8fGktrhPPo1IfnVXxRsNKXhrWQzfnKkYmalwGBdJ4FjdH8+AA3s0QXZBa6pJB orwON6S+Z23ORJ+AeRegR8WlIzOK209Pd8vxG1JgVGOnX0ftNSvFC9yPVFJM1lKH9cIQuucjE/V2D yh2z3WuaL6A/zX5GOylxEOjd1X4t0TZ/vxGf8oC8VubbqkQVL+1oj/zdODaOLiSfi4lowe43PL5My tZ35ravwA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k1Acm-0003Ak-Pk; Thu, 30 Jul 2020 15:37:40 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1k1Aa2-0001zh-D6 for linux-arm-kernel@lists.infradead.org; Thu, 30 Jul 2020 15:34:51 +0000 Received: from localhost.localdomain (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 40B7622B42; Thu, 30 Jul 2020 15:34:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596123289; bh=fZtxzvhOzdyXaAUD31LH6x+TDWxF0GaTJ2KbdQyLKbc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KB0czXdGBCexDuzVnPtg7/mCh6h7aT9IeEMov8rj1dzi1Aa1k9Vque37CLij0zfos Kviy0vEeOQ2NUB5ZXKS0T/3ii4xtTFu1sK0HXpsiGExu2JVMerhtZYg/s+4bFMqRJx 1ZOVzqOKORIMkvdUV7eDFX1oWcrcLmMUkWfCD9hQ= From: Will Deacon To: kvmarm@lists.cs.columbia.edu Subject: [PATCH 15/20] KVM: arm64: Add support for relaxing stage-2 perms in generic page-table code Date: Thu, 30 Jul 2020 16:34:01 +0100 Message-Id: <20200730153406.25136-16-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200730153406.25136-1-will@kernel.org> References: <20200730153406.25136-1-will@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200730_113450_615896_9581DE9F X-CRM114-Status: GOOD ( 16.74 ) X-Spam-Score: -5.2 (-----) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-5.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [198.145.29.99 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.0 DKIMWL_WL_HIGH DKIMwl.org - Whitelisted High sender X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kernel-team@android.com, Suzuki Poulose , Marc Zyngier , Quentin Perret , James Morse , Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Add support for relaxing the permissions of a stage-2 mapping (i.e. adding additional permissions) to the generic page-table code. Cc: Marc Zyngier Cc: Quentin Perret Signed-off-by: Will Deacon --- arch/arm64/include/asm/kvm_pgtable.h | 17 +++++++++++++++++ arch/arm64/kvm/pgtable.c | 20 ++++++++++++++++++++ 2 files changed, 37 insertions(+) diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index e4d99556a22f..36f0e9e88acd 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -198,6 +198,23 @@ kvm_pte_t kvm_pgtable_stage2_mkyoung(void *cookie, u64 addr); */ kvm_pte_t kvm_pgtable_stage2_mkold(void *cookie, u64 addr); +/** + * kvm_pgtable_stage2_relax_perms() - Relax the permissions enforced by a + * page-table entry. + * @cookie: Opaque cookie allocated by kvm_pgtable_stage2_alloc_cookie(). + * @addr: Intermediate physical address to identify the page-table entry. + * @prot: Additional permissions to grant for the mapping. + * + * If there is a valid, leaf page-table entry used to translate @addr, then + * relax the permissions in that entry according to the read, write and + * execute permissions specified by @prot. No permissions are removed, and + * TLB invalidation is performed after updating the entry. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_stage2_relax_perms(void *cookie, u64 addr, + enum kvm_pgtable_prot prot); + /** * kvm_pgtable_stage2_is_young() - Test whether a page-table entry has the * access flag set. diff --git a/arch/arm64/kvm/pgtable.c b/arch/arm64/kvm/pgtable.c index eb41f162a36a..14d8a1b2c4c1 100644 --- a/arch/arm64/kvm/pgtable.c +++ b/arch/arm64/kvm/pgtable.c @@ -800,6 +800,26 @@ bool kvm_pgtable_stage2_is_young(void *cookie, u64 addr) return !!(pte & KVM_PTE_LEAF_ATTR_LO_S2_AF); } +int kvm_pgtable_stage2_relax_perms(void *cookie, u64 addr, + enum kvm_pgtable_prot prot) +{ + int ret; + struct kvm_pgtable *pgt = cookie; + kvm_pte_t set = 0, clr = 0; + + if (prot & KVM_PGTABLE_PROT_R) + set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R; + + if (prot & KVM_PGTABLE_PROT_W) + set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W; + + if (prot & KVM_PGTABLE_PROT_X) + clr |= KVM_PTE_LEAF_ATTR_HI_S2_XN; + + ret = stage2_update_leaf_attrs(cookie, addr, 1, set, clr, NULL); + kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, pgt->mmu, addr, 0); + return ret; +} static int stage2_flush_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, enum kvm_pgtable_walk_flags flag,