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Date: Fri,  8 Aug 2025 10:42:03 +0800
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Cc: <alex@ghiti.fr>, <aou@eecs.berkeley.edu>, 
	<huangxianliang@lanxincomputing.com>, <iommu@lists.linux.dev>, 
	<joro@8bytes.org>, <linux-kernel@vger.kernel.org>, 
	<linux-riscv@lists.infradead.org>, <palmer@dabbelt.com>, 
	<paul.walmsley@sifive.com>, <robin.murphy@arm.com>, 
	<tjeznach@rivosinc.com>, <will@kernel.org>
Subject: Re: Re: [PATCH v?] iommu/riscv: check pte null pointer before use
References: <effb29be-6d14-47e5-ab71-454119467750@web.de>
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Received: from LeonHXL.localdomain ([116.237.111.137]) by smtp.feishu.cn with ESMTPS; Fri, 08 Aug 2025 10:42:15 +0800
From: "XianLiang Huang" <huangxianliang@lanxincomputing.com>

Sure, 'prevent' is much appropriate than 'check' here...

Prevent null pointer dereference in riscv_iommu_iova_to_phys(). Now, when
it's called with an unmapped iova, the kernel will not crash here.