From nobody Tue Feb 10 06:04:56 2026 Received: from mail-ed1-f73.google.com (mail-ed1-f73.google.com [209.85.208.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 907822080C5 for ; Mon, 16 Dec 2024 17:58:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734371915; cv=none; b=mZyKo5kRV6V22sEaetRP93HDblaomxGIwgunoTTJdI+67eO9gv9VKvrxWOg1A9xN0RoA7A6/y5pMJcrMPS8RSwILZakoAqvFnwiNh0n34+hC42xOANjVN8tpb6zMKG/lu7XgSq26UhMl/JAOZUXhxNy2Sm5yQ5Ivf0RobV2xayo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734371915; c=relaxed/simple; bh=x7+FYuhLRSc4489GTUBhq7A0rSYck1JVWFO7Y19Rgzo=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=IUWeC/HtqRLeDAg4GqmObxUeTxv/+gDQv5G8HImvNgCW0KkPegnG+rD6vR7EphFlb9Ulwr1/L2ua4BjelIlyJTcWsPtZmWrEs7VHn87WXaL84cU6D2P02wKsSwuUR2+rLl1WColgV3GyJkrpSXDstN5edeuFygxtbUpjUrJ+w04= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--qperret.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=3oIF6D3g; arc=none smtp.client-ip=209.85.208.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--qperret.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="3oIF6D3g" Received: by mail-ed1-f73.google.com with SMTP id 4fb4d7f45d1cf-5d3e4e09ae7so5078536a12.3 for ; Mon, 16 Dec 2024 09:58:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1734371912; x=1734976712; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=dyP52yXMvdCG/qeO/nxD7I5lO2ep30nuHc1XdZd9lVE=; b=3oIF6D3goZZTEXbWSh0xRbQkbHAueUEFneQWrbYvRukbh3Yx7KkN/dEeml0RbbBVav ZrNGfjgg3hcIw06N43wfXwoJQxO381v2/znbUjvoIoHInfO+as/nhH9600Z/MB+v6hG/ roUEK37wmhDrOnP9Owy26U+BByrSRvPEUQKba+qXHeAZpmSwYQhpPO/SInKqux6a6nLS L+uyKZVGzE+y9VMXZuZe9+QayK1gtr7HFV/kIjEcZcOaKu1dd9mjyS2fFtXEwC3/BKhO iun74XthlB6pmip1M6+rSOsT8Ez08B9mq13Y5KLKvUApEA097+/IDl9KwAbzQfkd3VPt rosg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1734371912; x=1734976712; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=dyP52yXMvdCG/qeO/nxD7I5lO2ep30nuHc1XdZd9lVE=; b=uIRBCRRW8Ya0GTWSK/sZ5W73ZDqW9bztbFhimbI2yqeR/gjYnkIIhdodd83ytQXg+Y 2DBIwvu5vZiyLbQgHWBP6X0CSChEi5v7V2YGNKZdDZ3DIn8yXdzJsnDFr7mt3LvXCsd8 OLkILOQyXTJOBcmCj07+10eLzJe+vpGrI0rTgAjYTRYQzjVWd1pCrGZhhOwj5Gro9mz2 hA+Ph01oN2r3VMBeMUNN9hFTvWf/0cqjA7hyyIGvajE1yckQdwSaPby//QjP9ov1NEC/ YlSmP8nB5b79O3NeTmOLvm1+WDpv3RAn/9ma9IPxrtiTs956LnagQldXfkJ8/0fD+eW2 KWig== X-Forwarded-Encrypted: i=1; AJvYcCW1rBtJVM88hgoqeUMhed0Jrsf3VAKXaXigmL6AEJB97whA/Te4dgBBBVx51oc9CtHutlu1GbdG5gGjLy4=@vger.kernel.org X-Gm-Message-State: AOJu0Ywsvx+q8XJnjGVz7D2zw24cV/nJNG8c50LQnlp4ej7JBicnWMjU zSOkkBqjfZBeZs6zFNgITN1H+UfwpqlT3qSZqiwjyHiScAoAmK1YMkOzEymtfHWJydgOVIQEXTp OTtivyg== X-Google-Smtp-Source: AGHT+IFP4nw4MedeF204ACC4I+mIvh9+F0wuQVKyEpLyYdXQPbpwYFvSWf+Gws8g2zlegmkHbaKOYI4g0Iku X-Received: from edbek21.prod.google.com ([2002:a05:6402:3715:b0:5d6:570c:dae5]) (user=qperret job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:5191:b0:5cf:bb9e:cca7 with SMTP id 4fb4d7f45d1cf-5d63c3c0697mr13666506a12.28.1734371910915; Mon, 16 Dec 2024 09:58:30 -0800 (PST) Date: Mon, 16 Dec 2024 17:57:57 +0000 In-Reply-To: <20241216175803.2716565-1-qperret@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241216175803.2716565-1-qperret@google.com> X-Mailer: git-send-email 2.47.1.613.gc27f4b7a9f-goog Message-ID: <20241216175803.2716565-13-qperret@google.com> Subject: [PATCH v3 12/18] KVM: arm64: Introduce __pkvm_host_relax_guest_perms() From: Quentin Perret To: Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon Cc: Fuad Tabba , Vincent Donnefort , Sebastian Ene , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Introduce a new hypercall allowing the host to relax the stage-2 permissions of mappings in a non-protected guest page-table. It will be used later once we start allowing RO memslots and dirty logging. Signed-off-by: Quentin Perret Reviewed-by: Fuad Tabba --- arch/arm64/include/asm/kvm_asm.h | 1 + arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 1 + arch/arm64/kvm/hyp/nvhe/hyp-main.c | 20 ++++++++++++++++ arch/arm64/kvm/hyp/nvhe/mem_protect.c | 23 +++++++++++++++++++ 4 files changed, 45 insertions(+) diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_= asm.h index 0b6c4d325134..66ee8542dcc9 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -67,6 +67,7 @@ enum __kvm_host_smccc_func { __KVM_HOST_SMCCC_FUNC___pkvm_host_unshare_hyp, __KVM_HOST_SMCCC_FUNC___pkvm_host_share_guest, __KVM_HOST_SMCCC_FUNC___pkvm_host_unshare_guest, + __KVM_HOST_SMCCC_FUNC___pkvm_host_relax_perms_guest, __KVM_HOST_SMCCC_FUNC___kvm_adjust_pc, __KVM_HOST_SMCCC_FUNC___kvm_vcpu_run, __KVM_HOST_SMCCC_FUNC___kvm_flush_vm_context, diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm= /hyp/include/nvhe/mem_protect.h index e528a42ed60e..a308dcd3b5b8 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h +++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h @@ -41,6 +41,7 @@ int __pkvm_host_share_ffa(u64 pfn, u64 nr_pages); int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages); int __pkvm_host_share_guest(u64 pfn, u64 gfn, struct pkvm_hyp_vcpu *vcpu, = enum kvm_pgtable_prot prot); int __pkvm_host_unshare_guest(u64 gfn, struct pkvm_hyp_vm *hyp_vm); +int __pkvm_host_relax_perms_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu, enu= m kvm_pgtable_prot prot); =20 bool addr_is_memory(phys_addr_t phys); int host_stage2_idmap_locked(phys_addr_t addr, u64 size, enum kvm_pgtable_= prot prot); diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/h= yp-main.c index 3c3a27c985a2..287e4ee93ef2 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -264,6 +264,25 @@ static void handle___pkvm_host_unshare_guest(struct kv= m_cpu_context *host_ctxt) cpu_reg(host_ctxt, 1) =3D ret; } =20 +static void handle___pkvm_host_relax_perms_guest(struct kvm_cpu_context *h= ost_ctxt) +{ + DECLARE_REG(u64, gfn, host_ctxt, 1); + DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 2); + struct pkvm_hyp_vcpu *hyp_vcpu; + int ret =3D -EINVAL; + + if (!is_protected_kvm_enabled()) + goto out; + + hyp_vcpu =3D pkvm_get_loaded_hyp_vcpu(); + if (!hyp_vcpu || pkvm_hyp_vcpu_is_protected(hyp_vcpu)) + goto out; + + ret =3D __pkvm_host_relax_perms_guest(gfn, hyp_vcpu, prot); +out: + cpu_reg(host_ctxt, 1) =3D ret; +} + static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt) { DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1); @@ -475,6 +494,7 @@ static const hcall_t host_hcall[] =3D { HANDLE_FUNC(__pkvm_host_unshare_hyp), HANDLE_FUNC(__pkvm_host_share_guest), HANDLE_FUNC(__pkvm_host_unshare_guest), + HANDLE_FUNC(__pkvm_host_relax_perms_guest), HANDLE_FUNC(__kvm_adjust_pc), HANDLE_FUNC(__kvm_vcpu_run), HANDLE_FUNC(__kvm_flush_vm_context), diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvh= e/mem_protect.c index 30243b7922f1..aa8e0408aebb 100644 --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c @@ -1488,3 +1488,26 @@ int __pkvm_host_unshare_guest(u64 gfn, struct pkvm_h= yp_vm *vm) =20 return ret; } + +int __pkvm_host_relax_perms_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu, enu= m kvm_pgtable_prot prot) +{ + struct pkvm_hyp_vm *vm =3D pkvm_hyp_vcpu_to_hyp_vm(vcpu); + u64 ipa =3D hyp_pfn_to_phys(gfn); + u64 phys; + int ret; + + if (prot & ~KVM_PGTABLE_PROT_RWX) + return -EINVAL; + + host_lock_component(); + guest_lock_component(vm); + + ret =3D __check_host_shared_guest(vm, &phys, ipa); + if (!ret) + ret =3D kvm_pgtable_stage2_relax_perms(&vm->pgt, ipa, prot, 0); + + guest_unlock_component(vm); + host_unlock_component(); + + return ret; +} --=20 2.47.1.613.gc27f4b7a9f-goog