From patchwork Wed Dec 1 17:04:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Quentin Perret X-Patchwork-Id: 12694354 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DFD08C433EF for ; Wed, 1 Dec 2021 17:08:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:References: Mime-Version:Message-Id:In-Reply-To:Date:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=P9wFHqRk7dnliVJl+T+lNSFCmkxtjQeB3xCc0+wwqws=; b=k9rUnKClWfsVqBE7iOCk8q5i/1 G5PjuzGX19HsMtKg/zO+3YBpkIjv5kOPLrWDZ38c25qzQrP95OkyUNAdZOnDdyjY5bcYoUFx+x4Bi 9UZdKnBzqrQ02jiDEIWXfUbYDMT13sK4qVmegbQkk17VjrmrM7VS+r45d42RkRDF2odCMIL5mcuF8 toRdg7IR0B14iw30cvWvtWDy9UIrvoFnUG/W2eutlFRoaC9oH7Fs6JLua06/6+O5+REvAgok/8kWc 0Pv5zi9h+WAgqVM/sdcPoRn8X8xrn+heNvv4IgqmEZv4p86mjZbMVvidN20msq5G5XAHLEfydBVMU 7CslOTdA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1msT3g-009Sde-Qq; Wed, 01 Dec 2021 17:06:17 +0000 Received: from mail-wm1-x34a.google.com ([2a00:1450:4864:20::34a]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1msT2B-009RuY-6f for linux-arm-kernel@lists.infradead.org; Wed, 01 Dec 2021 17:04:44 +0000 Received: by mail-wm1-x34a.google.com with SMTP id l6-20020a05600c4f0600b0033321934a39so1191331wmq.9 for ; Wed, 01 Dec 2021 09:04:42 -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=NJuegLyFty4h+k4BvUryfHfsyVJ26LHh21kFNoYVPms=; b=pjEZYfEFH2f9DZZLkJPc+DJKonqmGOFU+/IndvDwaAD0Mc38KaGhN+e2+ThY9Xkoie LyXXIL01+VTsQKZGzSG7BqPQx8sGPd7M0yPwve2btEpLEMaXtEoXnnm461+DFbQ1JuSF hVKeslduzUKxJvDgBe+SxkbHjOmG/IPTUQcWOBwoZm9RXnnQTefZq8EKI/qpAGZte/ig lFFXkNlytDGtJUhJPWkYUsGKCHLOFSLpEsdcuwsG6GsTNDLC1cXDgdJHgOrcZKjbIFVC 5UvpJAycHv+RaqfhaI2HTgGTD/ahlaWvkRYDC9DdisOszJzGcDRE3EN9f/dfRsXCxmde DbRw== 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=NJuegLyFty4h+k4BvUryfHfsyVJ26LHh21kFNoYVPms=; b=sPKf70aanSuRwbi2TxU8I1cspdPV7zLwQsjj3iLSKaDjkzN2uuLgYdbyiFw5Xt8qjR DoKQQPTvbA881HxiCT3oQJ2quU6ZVpf/tMv4lX26Z1OstO1Ak4iUI6aEusLgTiVO6VkP dSWt7Bi/DC6BoCFCPirZ+/+do17P231EJmmIwd2qod+OaZR74ZnqRzWJPEFs5ruTy/+U AV7FmzlTqNGNQPOcauJf0ALtrTpjCcykLEB2b4N4KRcoZi/6e0U5J5O0hVtwlSztC7Rn INa7Ixe+JtjUn4fUqpkU0tqn4rmwCfXuMEtTE5AuXETbE6gYzZnlOvQAMcKhcK+Su17M bEHA== X-Gm-Message-State: AOAM533CCc5awMZfGoo8yykQCEBUQ91ZV69UHaIDbP2e4DEGhmmXE7q5 Vonq9bHgoigHfkEHOqwfx7NjUppxfivw X-Google-Smtp-Source: ABdhPJxCJlvPNxfX1Vbthcz7eOfsb4kNC+DIdOG4XHH/CTzEgT2hYZqSk1komsbwuqasr1MGCR4/qh/O+mWH X-Received: from luke.lon.corp.google.com ([2a00:79e0:d:210:1cab:1a20:2ef1:ddde]) (user=qperret job=sendgmr) by 2002:a1c:a592:: with SMTP id o140mr8609740wme.10.1638378281534; Wed, 01 Dec 2021 09:04:41 -0800 (PST) Date: Wed, 1 Dec 2021 17:04:01 +0000 In-Reply-To: <20211201170411.1561936-1-qperret@google.com> Message-Id: <20211201170411.1561936-8-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 07/15] KVM: arm64: Introduce kvm_share_hyp() 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211201_090443_331058_0BABA951 X-CRM114-Status: GOOD ( 19.89 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The create_hyp_mappings() function can currently be called at any point in time. However, its behaviour in protected mode changes widely depending on when it is being called. Prior to KVM init, it is used to create the temporary page-table used to bring-up the hypervisor, and later on it is transparently turned into a 'share' hypercall when the kernel has lost control over the hypervisor stage-1. In order to prepare the ground for also unsharing pages with the hypervisor during guest teardown, introduce a kvm_share_hyp() function to make it clear in which places a share hypercall should be expected, as we will soon need a matching unshare hypercall in all those places. Signed-off-by: Quentin Perret --- arch/arm64/include/asm/kvm_mmu.h | 1 + arch/arm64/kvm/arm.c | 4 ++-- arch/arm64/kvm/fpsimd.c | 2 +- arch/arm64/kvm/mmu.c | 27 +++++++++++++++++++++------ arch/arm64/kvm/reset.c | 2 +- 5 files changed, 26 insertions(+), 10 deletions(-) diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 02d378887743..185d0f62b724 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -150,6 +150,7 @@ static __always_inline unsigned long __kern_hyp_va(unsigned long v) #include #include +int kvm_share_hyp(void *from, void *to); int create_hyp_mappings(void *from, void *to, enum kvm_pgtable_prot prot); int create_hyp_io_mappings(phys_addr_t phys_addr, size_t size, void __iomem **kaddr, diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 9b745d2bc89a..c202abb448b1 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -146,7 +146,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) if (ret) return ret; - ret = create_hyp_mappings(kvm, kvm + 1, PAGE_HYP); + ret = kvm_share_hyp(kvm, kvm + 1); if (ret) goto out_free_stage2_pgd; @@ -342,7 +342,7 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) if (err) return err; - return create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP); + return kvm_share_hyp(vcpu, vcpu + 1); } void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) diff --git a/arch/arm64/kvm/fpsimd.c b/arch/arm64/kvm/fpsimd.c index 5526d79c7b47..86899d3aa9a9 100644 --- a/arch/arm64/kvm/fpsimd.c +++ b/arch/arm64/kvm/fpsimd.c @@ -30,7 +30,7 @@ int kvm_arch_vcpu_run_map_fp(struct kvm_vcpu *vcpu) struct user_fpsimd_state *fpsimd = ¤t->thread.uw.fpsimd_state; /* Make sure the host task fpsimd state is visible to hyp: */ - ret = create_hyp_mappings(fpsimd, fpsimd + 1, PAGE_HYP); + ret = kvm_share_hyp(fpsimd, fpsimd + 1); if (!ret) vcpu->arch.host_fpsimd_state = kern_hyp_va(fpsimd); diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index f8f1096a297f..fd868fb9d922 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -299,6 +299,25 @@ static int pkvm_share_hyp(phys_addr_t start, phys_addr_t end) return 0; } +int kvm_share_hyp(void *from, void *to) +{ + if (is_kernel_in_hyp_mode()) + return 0; + + /* + * The share hcall maps things in the 'fixed-offset' region of the hyp + * VA space, so we can only share physically contiguous data-structures + * for now. + */ + if (is_vmalloc_addr(from) || is_vmalloc_addr(to)) + return -EINVAL; + + if (kvm_host_owns_hyp_mappings()) + return create_hyp_mappings(from, to, PAGE_HYP); + + return pkvm_share_hyp(__pa(from), __pa(to)); +} + /** * create_hyp_mappings - duplicate a kernel virtual address range in Hyp mode * @from: The virtual kernel start address of the range @@ -319,12 +338,8 @@ int create_hyp_mappings(void *from, void *to, enum kvm_pgtable_prot prot) if (is_kernel_in_hyp_mode()) return 0; - if (!kvm_host_owns_hyp_mappings()) { - if (WARN_ON(prot != PAGE_HYP)) - return -EPERM; - return pkvm_share_hyp(kvm_kaddr_to_phys(from), - kvm_kaddr_to_phys(to)); - } + if (!kvm_host_owns_hyp_mappings()) + return -EPERM; start = start & PAGE_MASK; end = PAGE_ALIGN(end); diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index c7a0249df840..e3e2a79fbd75 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -113,7 +113,7 @@ static int kvm_vcpu_finalize_sve(struct kvm_vcpu *vcpu) if (!buf) return -ENOMEM; - ret = create_hyp_mappings(buf, buf + reg_sz, PAGE_HYP); + ret = kvm_share_hyp(buf, buf + reg_sz); if (ret) { kfree(buf); return ret;