Hi Will, On 3/2/2018 5:30 AM, Will Deacon wrote: >> Do you really have to reset the IOMMU? Can you just give it new page >> tables that start out with all IOVAs from all devices being invalid, >> then add valid mappings as drivers need them (presumably after the >> driver has done whatever it needs to so the device stops using the old >> DMA addresses)? > We already have the option to do that via the command line using the > disable_bypass option, so it just sounds like we need to take this into > account when resetting the SMMU to take care that GBPA is configured so > that transactions are terminated when SMMUEN=0. How about the points that Baoquan highlighted in his email regarding the solution from AMD and X86? I have not read the entire thread but, is this just a matter of following what Bjorn recommended or there is more to it? Sinan -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
