From patchwork Mon Aug 19 13:19:19 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Price X-Patchwork-Id: 13768358 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C530616CD18; Mon, 19 Aug 2024 13:20:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724073643; cv=none; b=QCZ+8BFm2VE0Ej6rKF4G2Ac4ferhlWWvRpEIeV4INOHj+hROFT81+Ni+cg8AMBJQ0QKbaSLKXzvzx9jhMymkEqkF6n2U5bkNoDuH4NXBOohu8p9xucUb8r76YSbKfhCRDiihQpLPcxIdYzDBjDq2rdk5jnJWbY9KXZRKmHjzh9k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724073643; c=relaxed/simple; bh=KaLWr6YZb+PWvDZSNXabheOdGWtip51iowgdcysufRw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=YDkFVGJ26CN/kRkY/wIF9S7rwiB8Fiif6rwrqFwN9YbIZrIauNty2oosY9C1vCKBJvI1twKNZPwRNyhEE5vFaQKJ8QH6yzc2zoQUsjpHxMO22y6R6KX4r8tkLSdm+bR4NnD8iuOnLrL/ouWOY0WYYhfhniXZGYNW39QZZ6i3OT4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3EE82339; Mon, 19 Aug 2024 06:21:07 -0700 (PDT) Received: from e122027.arm.com (unknown [10.57.85.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2AAAE3F73B; Mon, 19 Aug 2024 06:20:37 -0700 (PDT) From: Steven Price To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Steven Price , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Suzuki K Poulose , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Gavin Shan , Shanker Donthineni , Alper Gun Subject: [PATCH v5 14/19] arm64: Enforce bounce buffers for realm DMA Date: Mon, 19 Aug 2024 14:19:19 +0100 Message-Id: <20240819131924.372366-15-steven.price@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240819131924.372366-1-steven.price@arm.com> References: <20240819131924.372366-1-steven.price@arm.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Within a realm guest it's not possible for a device emulated by the VMM to access arbitrary guest memory. So force the use of bounce buffers to ensure that the memory the emulated devices are accessing is in memory which is explicitly shared with the host. This adds a call to swiotlb_update_mem_attributes() which calls set_memory_decrypted() to ensure the bounce buffer memory is shared with the host. For non-realm guests or hosts this is a no-op. Co-developed-by: Suzuki K Poulose Signed-off-by: Suzuki K Poulose Signed-off-by: Steven Price Reviewed-by: Catalin Marinas --- v3: Simplify mem_init() by using a 'flags' variable. --- arch/arm64/kernel/rsi.c | 1 + arch/arm64/mm/init.c | 10 +++++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c index 5c2c977a50fb..69d8d9791c65 100644 --- a/arch/arm64/kernel/rsi.c +++ b/arch/arm64/kernel/rsi.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 9b5ab6818f7f..1d595b63da71 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -41,6 +41,7 @@ #include #include #include +#include #include #include #include @@ -369,8 +370,14 @@ void __init bootmem_init(void) */ void __init mem_init(void) { + unsigned int flags = SWIOTLB_VERBOSE; bool swiotlb = max_pfn > PFN_DOWN(arm64_dma_phys_limit); + if (is_realm_world()) { + swiotlb = true; + flags |= SWIOTLB_FORCE; + } + if (IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC) && !swiotlb) { /* * If no bouncing needed for ZONE_DMA, reduce the swiotlb @@ -382,7 +389,8 @@ void __init mem_init(void) swiotlb = true; } - swiotlb_init(swiotlb, SWIOTLB_VERBOSE); + swiotlb_init(swiotlb, flags); + swiotlb_update_mem_attributes(); /* this will put all unused low memory onto the freelists */ memblock_free_all();