From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH v5 12/16] PCI: Add pci_iomap_host_shared(),
 pci_iomap_host_shared_range()
Date: Tue, 12 Oct 2021 17:18:28 -0400
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To: Dan Williams <dan.j.williams@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>, Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>, Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>, Peter Zijlstra <peterz@infradead.org>, Andy Lutomirski <luto@kernel.org>, Bjorn Helgaas <bhelgaas@google.com>, Richard Henderson <rth@twiddle.net>, Thomas Bogendoerfer <tsbogend@alpha.franken.de>, James E J Bottomley <James.Bottomley@hansenpartnership.com>, Helge Deller <deller@gmx.de>, "David S . Miller" <davem@davemloft.net>, Arnd Bergmann <arnd@arndb.de>, Jonathan Corbet <corbet@lwn.net>, Paolo Bonzini <pbonzini@redhat.com>, David Hildenbrand <david@redhat.com>, Andrea Arcangeli <aarcange@redhat.com>, Josh Poimboeuf <jpoimboe@redhat.c>

On Tue, Oct 12, 2021 at 02:14:44PM -0700, Dan Williams wrote:
> Especially in this case where the virtio use case being
> opted-in is *already* in a path that has been authorized by the
> device-filter policy engine.

That's a good point. Andi, how about setting a per-device flag
if its ID has been allowed and then making pci_iomap create
a shared mapping transparently?

-- 
MST