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To: <markus.elfring@web.de>
Subject: Re: Re: [PATCH v?] iommu/riscv: check pte null pointer before use
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From: "XianLiang Huang" <huangxianliang@lanxincomputing.com>
Date: Fri,  8 Aug 2025 10:42:03 +0800
X-Original-From: XianLiang Huang <huangxianliang@lanxincomputing.com>
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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

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.