On Tue, 2015-03-24 at 16:48 -0400, Robbie VanVossen wrote: > If multiple devices are being passed through to the same domain and they > share a single SMMU, then they only require a single iommu_domain. > > In arm_smmu_assign_dev, before a new iommu_domain is created, the > xen_domain->contexts is checked for any iommu_domains that are already > assigned to device that uses the same SMMU as the current device. If one > is found, attach the device to that iommu_domain. If a new one isn't > found, create a new iommu_domain just like before. > > The arm_smmu_deassign_dev function assumes that there is a single > device per iommu_domain. This meant that when the first device was > deassigned, the iommu_domain was freed and when another device was > deassigned a crash occurred in xen. > > To fix this, a reference counter was added to the iommu_domain struct. > When an arm_smmu_xen_device references an iommu_domain, the > iommu_domains ref is incremented. When that reference is removed, the > iommu_domains ref is decremented. The iommu_domain will only be freed > when the ref is 0. > > Signed-off-by: Robbie VanVossen <robert.vanvos...@dornerworks.com> > Reviewed-by: Julien Grall <julien.gr...@linaro.org>
I was expecting this to come back in a new version of Julien's passthrough series, but Julien prodded me to say that this patch didn't actually have any dependency/interaction with his passthrough series like I thought, so it can go in now. So Acked + applied, sorry for the delay. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
