The virtio specification says:

"The descriptors used for a buffer should not effect the semantics
of the message,
except for the total length of the buffer"

and

"In particular, no implementation should use the descriptor boundaries
to determine the size of any header in a request"

Why should descriptor layout not be specified?

It seems that implementing arbitrary descriptor layout support (e.g.
1-byte descriptors) requires more code and makes input validation
harder.

Why bother with the flexibility of unspecified descriptor layouts?  As
long as the layout is specified clearly it makes everyone's lives
easier to use a strict descriptor layout.

The only reason I can think of is that virtio should work over
transports that do not have the concept of "descriptors" (non-vring
transports like pipes or streams).

Stefan
_______________________________________________
Virtualization mailing list
[email protected]
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

Reply via email to