On Tue, 28 Apr 2020 12:07:25 -0700 "Luck, Tony" <tony.l...@intel.com> wrote:
> > If fd release cleans up then how should there be something in > > flight at the final mmdrop? > > ENQCMD from the user is only synchronous in that it lets the user > know their request has been added to a queue (or not). Execution of > the request may happen later (if the device is busy working on > requests for other users). The request will take some time to > complete. Someone told me the theoretical worst case once, which I've > since forgotten, but it can be a long time. > > So the driver needs to use flush/drain operations to make sure all > the in-flight work has completed before releasing/re-using the PASID. > Are you suggesting we should let driver also hold a reference of the PASID? > -Tony _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
