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Subject: Re: [RFC v2-fix 1/1] x86/tdx: Handle in-kernel MMIO
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From:   Andi Kleen <ak@linux.intel.com>
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Date:   Tue, 18 May 2021 13:56:04 -0700
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> virtio-pci, which is going to used by pretty much all traditional VMs, uses iomap.
> See vp_get(), vp_set(), and all the vp_io{read,write}*() wrappers.

That's true. But there are still all the other users. So it doesn't 
solve the problem. In the end I'm fairly sure we would need to patch 
readl/writel and friends.

-Andi