On 06.05.2025 10:31, Roger Pau Monne wrote: > Such flag is added to the domain create hypercall, and a matching option is > added to xl and libxl to set the flag: `cache_control`. When the flag is > set, the domain is allowed the usage of cache control operations. If the > flag is not explicitly set, libxl will set it if the domain has any `iomem` > or `ioports` ranges assigned. > > Modify cache_flush_permitted() helper so that it's return value is no > longer based on the IO resources assigned to the domain, but rather whether > the domain has been explicitly allowed control over the cache, or if it has > IOMMU support and there's a single IOMMU in the system that doesn't allow > forcing snooping behind the guest back. As a result of this, the return of > cache_flush_permitted() is constant for the lifetime of a domain, based on > the domain creation flags and the capabilities of the IOMMU if enabled > for the domain.
This then further emphasizes the remark made for patch 7. Jan
