On Tue, Dec 05, 2023 at 09:33:30AM -0800, Nicolin Chen wrote: > On Mon, Dec 04, 2023 at 10:48:50AM -0400, Jason Gunthorpe wrote: > > > > Or am I missing some point here? > > > > It sounds Ok, we just have to understand what userspace should be > > doing and how much of this the kernel should implement. > > > > It seems to me that the error code should return the gerror and the > > req_num should indicate the halted cons. The vmm should relay both > > into the virtual registers. > > I see your concern. I will take a closer look and see if we can > add to the initial version of arm_smmu_cache_invalidate_user(). > Otherwise, we can add later. > > Btw, VT-d seems to want the error_code and reports in the VT-d > specific invalidate entry structure, as Kevin and Yi had that > discussion in the other side of the thread. It could be fine to shift it into the driver data blob. It isn't really generic in the end. Jason