From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f74.google.com (mail-wr1-f74.google.com [209.85.221.74]) (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 A171A39EF1D for ; Fri, 1 May 2026 11:20:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777634410; cv=none; b=rgRcTDkam+O1dnAcylWnjGDfgi+HbHdbIwhg2aXwZd9JszcYwOzen+UALiZfouafstvW/3EXb3aaeXMxvnUS7GvSmFCT2DainNw7CFo00mEG59sORckGtXtlMUZgJJhFh3GsXerViXCR/MrCH3QT/6Nx/LW6YwhF+kTQCvNxAZY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777634410; c=relaxed/simple; bh=7BiQeDIdExKTrYvjjivfx/XCGpvMdX1OxrkfqO2/Rss=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=ulmfE76ujgp3DOeTLQtDPYobZAcUQvCt3I1jbJLLLD+R10c/X7sUPq0Ual065V4zSPwqBKnJD3KB1N04ylTaCTX+ZEpcuat3mceaCaosc9Yq18cbqpJkOJsKy4bcUsY3L970MPCs/8phgSZe3Ev2F2PSiz8qo+dwYvGv/OeVpWs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--smostafa.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=LfhZhGxU; arc=none smtp.client-ip=209.85.221.74 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--smostafa.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="LfhZhGxU" Received: by mail-wr1-f74.google.com with SMTP id ffacd0b85a97d-43ff19e54beso1245379f8f.2 for ; Fri, 01 May 2026 04:20:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1777634407; x=1778239207; 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=PcUXILApPYbJmZVAe9rvUD8ScMEsBCpayhLYZpcyGpA=; b=LfhZhGxU02n2MIRYReD6HaNMLjy/cUL3IQ5EyHeXXksGb7sWaxmuV/+XnVITxd0QVH S763XdaXQvZXWZh0+fjKSW9uwIz74e+EdLjLXapKk9ZjMm4IqZy4AALR8sP1vFXmZYuk 6CBkxCq7OiG4WEHZnhqczB7Hz0PGE+ZVqdZuJms9Xvfcno39IWHrmki3obfGbDuQrVca QZ8OQU07Tk+tfRqt9/LAAm+Cy0iF5v7u/vEpKBI05WIfQ2hsbav01WLeSip4lRnoCwt5 6o6B7u38J8jR7HdIIU7gVmpSASX3QBLU6xL8RwbeKDZZST2iiQcCZhN+pEvr3HCuEW0X ADDQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1777634407; x=1778239207; 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=PcUXILApPYbJmZVAe9rvUD8ScMEsBCpayhLYZpcyGpA=; b=UEO7zJR72zZpSZ+caU3oH7tJj6ZjLjeVZQ03QcmPHU3D7h2LYQTNvwr8gA4Dojnug6 KwszFHWvdSt/eKmaY0Sq/mRiXVNaRXs0rEGxsrm6HfqOBzsP7ZG9grPSOsnV7Skvz8Rf EFcl0WRHQIQ5biQs/mlI4vEUbYf+iStXbeIaqbvV8aixvpuQcYp1OLRA5kgA7tS4T2DL J3fwtc3Eo2Dl/imuwy4iPs9oNkfrCM25bp7RO31ZnEEB66gSiYuXv3DG3AEyMozu3sBG OaEnHQOAxJyerGLxEFvI9Pqp/FHP1e5q8Xt9dkVnXQh9+PMIRPjD7N+k3r09ewXTQqkX CfDg== X-Forwarded-Encrypted: i=1; AFNElJ82nGSKZ3Kjx7v2r54OIEXU6+ZVc3J/nlLjvryW6dGYCtS6A/saXADqnjQbQKgt8dGTyDdhM0r9aCi0Iqw=@vger.kernel.org X-Gm-Message-State: AOJu0Yy9+mqTTVgQnL7rFn+xkG1x3zEc7RLl8f4oP5gV+fxZfLYHl71M yQ9K51T9IWKChV0kx59fJwcYco6Ceferwb8ToAgxmTVtDvd9HlohHerxlR+lqvd97Hw6CQImLi/ eJc/FGwSkbVYuxQ== X-Received: from wmrk4.prod.google.com ([2002:a05:600c:b44:b0:48a:6a1b:6c3b]) (user=smostafa job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600d:a:b0:489:1d74:56d with SMTP id 5b1f17b1804b1-48a84532792mr89794945e9.29.1777634406991; Fri, 01 May 2026 04:20:06 -0700 (PDT) Date: Fri, 1 May 2026 11:19:09 +0000 In-Reply-To: <20260501111928.259252-1-smostafa@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260501111928.259252-1-smostafa@google.com> X-Mailer: git-send-email 2.54.0.545.g6539524ca2-goog Message-ID: <20260501111928.259252-8-smostafa@google.com> Subject: [PATCH v6 07/25] KVM: arm64: iommu: Introduce IOMMU driver infrastructure From: Mostafa Saleh To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kvmarm@lists.linux.dev, iommu@lists.linux.dev Cc: catalin.marinas@arm.com, will@kernel.org, maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, joro@8bytes.org, jean-philippe@linaro.org, jgg@ziepe.ca, mark.rutland@arm.com, qperret@google.com, tabba@google.com, vdonnefort@google.com, sebastianene@google.com, keirf@google.com, Mostafa Saleh Content-Type: text/plain; charset="UTF-8" To establish DMA isolation, KVM needs an IOMMU driver which provides ops implemented at EL2. Only one driver can be used and is registered with kvm_iommu_register_driver() by passing pointer to the ops. This must be called before module_init() which is the point KVM initializes. Signed-off-by: Jean-Philippe Brucker Signed-off-by: Mostafa Saleh --- arch/arm64/include/asm/kvm_host.h | 5 +++++ arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/hyp/include/nvhe/iommu.h | 13 +++++++++++++ arch/arm64/kvm/hyp/nvhe/Makefile | 3 ++- arch/arm64/kvm/hyp/nvhe/iommu/iommu.c | 20 +++++++++++++++++++ arch/arm64/kvm/hyp/nvhe/setup.c | 5 +++++ arch/arm64/kvm/iommu.c | 26 +++++++++++++++++++++++++ 7 files changed, 72 insertions(+), 2 deletions(-) create mode 100644 arch/arm64/kvm/hyp/include/nvhe/iommu.h create mode 100644 arch/arm64/kvm/hyp/nvhe/iommu/iommu.c create mode 100644 arch/arm64/kvm/iommu.c diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 851f6171751c..52898d2a3ec6 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -1733,4 +1733,9 @@ static __always_inline enum fgt_group_id __fgt_reg_to_group_id(enum vcpu_sysreg long kvm_get_cap_for_kvm_ioctl(unsigned int ioctl, long *ext); +#ifndef __KVM_NVHE_HYPERVISOR__ +struct kvm_iommu_ops; +int kvm_iommu_register_driver(struct kvm_iommu_ops *hyp_ops); +#endif + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 59612d2f277c..0ddef54f7434 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -24,7 +24,7 @@ kvm-y += arm.o mmu.o mmio.o psci.o hypercalls.o pvtime.o \ vgic/vgic-mmio.o vgic/vgic-mmio-v2.o \ vgic/vgic-mmio-v3.o vgic/vgic-kvm-device.o \ vgic/vgic-its.o vgic/vgic-debug.o vgic/vgic-v3-nested.o \ - vgic/vgic-v5.o + vgic/vgic-v5.o iommu.o kvm-$(CONFIG_HW_PERF_EVENTS) += pmu-emul.o pmu.o kvm-$(CONFIG_ARM64_PTR_AUTH) += pauth.o diff --git a/arch/arm64/kvm/hyp/include/nvhe/iommu.h b/arch/arm64/kvm/hyp/include/nvhe/iommu.h new file mode 100644 index 000000000000..1ac70cc28a9e --- /dev/null +++ b/arch/arm64/kvm/hyp/include/nvhe/iommu.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ARM64_KVM_NVHE_IOMMU_H__ +#define __ARM64_KVM_NVHE_IOMMU_H__ + +#include + +struct kvm_iommu_ops { + int (*init)(void); +}; + +int kvm_iommu_init(void); + +#endif /* __ARM64_KVM_NVHE_IOMMU_H__ */ diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index 89d0533921f9..606c0e1b7bd0 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -24,7 +24,8 @@ CFLAGS_switch.nvhe.o += -Wno-override-init hyp-obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \ hyp-main.o hyp-smp.o psci-relay.o early_alloc.o page_alloc.o \ - cache.o setup.o mm.o mem_protect.o sys_regs.o pkvm.o stacktrace.o ffa.o + cache.o setup.o mm.o mem_protect.o sys_regs.o pkvm.o stacktrace.o ffa.o \ + iommu/iommu.o hyp-obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \ ../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o ../vgic-v5-sr.o clock.o hyp-obj-y += ../../../kernel/smccc-call.o diff --git a/arch/arm64/kvm/hyp/nvhe/iommu/iommu.c b/arch/arm64/kvm/hyp/nvhe/iommu/iommu.c new file mode 100644 index 000000000000..406c8fb9b3b9 --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/iommu/iommu.c @@ -0,0 +1,20 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * IOMMU operations for pKVM + * + * Copyright (C) 2022 Linaro Ltd. + */ +#include + +/* Only one set of ops supported */ +struct kvm_iommu_ops *kvm_iommu_ops; + + +int kvm_iommu_init(void) +{ + /* Keep DMA isolation optional. */ + if (!kvm_iommu_ops || !kvm_iommu_ops->init) + return 0; + + return kvm_iommu_ops->init(); +} diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c index 8041f6e80cd1..1f6b221db9a0 100644 --- a/arch/arm64/kvm/hyp/nvhe/setup.c +++ b/arch/arm64/kvm/hyp/nvhe/setup.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -329,6 +330,10 @@ void __noreturn __pkvm_init_finalise(void) if (ret) goto out; + ret = kvm_iommu_init(); + if (ret) + goto out; + ret = hyp_ffa_init(ffa_proxy_pages); if (ret) goto out; diff --git a/arch/arm64/kvm/iommu.c b/arch/arm64/kvm/iommu.c new file mode 100644 index 000000000000..f247384fa193 --- /dev/null +++ b/arch/arm64/kvm/iommu.c @@ -0,0 +1,26 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2025 Google LLC + * Author: Mostafa Saleh + */ + +#include + +extern struct kvm_iommu_ops *kvm_nvhe_sym(kvm_iommu_ops); + +static DEFINE_MUTEX(kvm_iommu_reg_lock); + +int kvm_iommu_register_driver(struct kvm_iommu_ops *hyp_ops) +{ + guard(mutex)(&kvm_iommu_reg_lock); + + /* Only protected KVM before de-privilege. */ + if (!is_protected_kvm_enabled() || is_kvm_arm_initialised()) + return -EINVAL; + + if (kvm_nvhe_sym(kvm_iommu_ops)) + return -EBUSY; + + kvm_nvhe_sym(kvm_iommu_ops) = hyp_ops; + return 0; +} -- 2.54.0.545.g6539524ca2-goog