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bhyve: add suport for other mappings in the MSI-X table page
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Authored by bz on Tue, Jul 20, 3:19 PM.


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Intel AX200 seems to map other usable address space into the
same page holding the the MSI-X table (which may be against the spec).
Map the host view of MSI-X Table page of the bar and perform
reads/writes on that for anything not covered by the MSI-X PBA or
the MSI-X Table.

Many thanks to grehan and jhb for helping to figure this out.

Sponsored by: The FreeBSD Foundation

Diff Detail

rS FreeBSD src repository - subversion
Lint OK
No Unit Test Coverage
Build Status
Buildable 40561
Build 37450: arc lint + arc unit

Event Timeline

bz requested review of this revision.Tue, Jul 20, 3:19 PM

There is still an issue with this I believe in case the Table grows larger than 1 page.
now I would hope that we would never see these kinds of devices but I'll leave this and other things to the review.

For others showing the MSI-X Table not in a different bar:

bar   [10] = type Memory, range 64, base 0x9e200000, size 16384, enabled
    cap 11[80] = MSI-X supports 16 messages, enabled
                 Table in map 0x10[0x2000], PBA in map 0x10[0x3000]

and a random read/write from within the same page as the MSI-X Table as seen:

passthru_read: baridx 0 msixtabbar 0 offset 0x2804 size 4 val 0x2affe0 error 0
passthru_write:1071: baridx 0 msixtabbar 0 offset 0x2804 size 4 val 0x28ffe0 error 0