From patchwork Mon Jul 1 09:54:57 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Price X-Patchwork-Id: 13717718 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 5109E14BF97; Mon, 1 Jul 2024 09:55:41 +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=1719827742; cv=none; b=V+xghUIGzBycY/teTSW8XI/tZd+YtkRIz3HmtgLJos3Vat00kSDC6Zhk2y5GZZjSe3PAlPIsONW/PUAASUq2NLtSrVH2Pn6qBt5FUl2wWIw103pcIoLl00aso9OOLscxSlQKoyRF7rvCbbsu2U32u1rlGBT9OY2EqGAsTyABanM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719827742; c=relaxed/simple; bh=cVh1MxUOGv76W88LdDecLvgPg8RG2FpI/Xa6L4O/K4k=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=UUAXxQ4vCHHQ6v3GWnc3EBNzZMeYBI6Fz/yE+mJP6NochKLM558X1HTTJO1+sKz7A0mL8rDE6vBtuxypztcCU+wAb+T3Hd7iyOKGv1MGR2Au1JToUjCihLZyrQRz16C3Dk2/DS4e0g8Uu/SJF688Eob2T8gkOTnTpCkKrGX13XQ= 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 F24A6339; Mon, 1 Jul 2024 02:56:05 -0700 (PDT) Received: from e122027.arm.com (unknown [10.57.44.170]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6BD143F762; Mon, 1 Jul 2024 02:55:38 -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 Subject: [PATCH v4 07/15] arm64: Enforce bounce buffers for realm DMA Date: Mon, 1 Jul 2024 10:54:57 +0100 Message-Id: <20240701095505.165383-8-steven.price@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240701095505.165383-1-steven.price@arm.com> References: <20240701095505.165383-1-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 --- v3: Simplify mem_init() by using a 'flags' variable. --- arch/arm64/kernel/rsi.c | 2 ++ arch/arm64/mm/init.c | 10 +++++++++- 2 files changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c index 7ac5fc4a27d0..918db258cd4a 100644 --- a/arch/arm64/kernel/rsi.c +++ b/arch/arm64/kernel/rsi.c @@ -6,6 +6,8 @@ #include #include #include +#include + #include struct realm_config config; 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();