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Date:   Wed, 2 Feb 2022 00:12:17 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Tianyu Lan <ltykernel@gmail.com>
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Subject: Re: [PATCH 0/2] x86/hyperv/Swiotlb: Add swiotlb_alloc_from_low_pages
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I think this interface is a little too hacky.  In the end all the
non-trusted hypervisor schemes (including the per-device swiotlb one)
can allocate the memory from everywhere and want for force use of
swiotlb.  I think we need some kind of proper interface for that instead
of setting all kinds of global variables.