>>> On 21.01.15 at 11:37, <julien.gr...@linaro.org> wrote: > On 21/01/2015 10:23, Jan Beulich wrote: >>>>> On 20.01.15 at 18:11, <julien.gr...@linaro.org> wrote: >>> While this function is currently only used for DOM0, this will be used >>> in a later patch for guest non-PCI passthrough. >> >> Okay, but you shouldn't break (or alter in [seemingly] benign ways) the >> Dom0 case imo. > > As iommu_hwdom_init is initialized correctly the IOMMU for DOM0, > iommu_construct is a no-op. > > Would an if ( need_iommu(d) ) will be more clear? Maybe we an assert > (!is_hardware_domain(d)).
Just think this through properly: iommu_hwdom_init() may leave Dom0's ->need_iommu at 0 or 1 (depending on iommu_dom0_strict). And iommu_construct() specifically is a nop only when ->need_iommu is positive (x86's arch_iommu_populate_page_table() sets it to a negative value to indicate "being set up", and I wonder how ARM gets away without doing so). Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
