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Date: Mon, 2 Dec 2019 08:22:18 +0100
From: Christoph Hellwig <hch@lst.de>
To: lijiazi <jqqlijiazi@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Robin Murphy <robin.murphy@arm.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	lijiazi <lijiazi@xiaomi.com>, iommu@lists.linux-foundation.org,
	linux-mm@kvack.org
Subject: Re: [PATCH] dma-mapping: do not mapping module memory
Message-ID: <20191202072218.GB29554@lst.de>
References: <d6a63ad37b2556b8ba2fda16fc4dde95aa721741.1574997534.git.lijiazi@xiaomi.com>
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On Fri, Nov 29, 2019 at 07:03:40PM +0800, lijiazi wrote:
> On ARM, x86_64, sparc64 platform, virt_to_page only convert a
> _valid_ virtual address to struct page *, virt_addr_valid(x)
> indicates whether a virtual address is valid. If ptr is point
> to a static variable in module area, virt_to_page will return
> a invalid value.

While the path isn't wrong, why bother?