On 12/15/21 2:35 AM, Pierre Morel wrote:
On 12/7/21 22:04, Matthew Rosato wrote:
Note: The first 3 patches of this series are included as pre-reqs, but
should be pulled via a separate series. Also, patch 5 is needed to
support 5.16+ linux header-sync and was already done by Paolo but not
merged yet so is thus included here as well.
For QEMU, the majority of the work in enabling instruction interpretation
is handled via new VFIO ioctls to SET the appropriate interpretation and
interrupt forwarding modes, and to GET the function handle to use for
interpretive execution.
This series implements these new ioctls, as well as adding a new,
optional
'intercept' parameter to zpci to request interpretation support not be
used
as well as an 'intassist' parameter to determine whether or not the
firmware assist will be used for interrupt delivery or whether the host
will be responsible for delivering all interrupts.
In which circumstances do we have an added value by not using interrupt
delivered by firmware?
Disabling it can be a tool to debug and assist in problem determination,
but that's about the only scenario I can think of where you would
intentionally want to disable intassist. Perhaps then it's not worth
leaving in place.
