On Thu, Aug 21, 2025 at 08:22:06AM -0700, Nicolin Chen wrote: > I should have pasted the full piece: > drivers/gpu/drm/tegra/drm.c-960- /* > drivers/gpu/drm/tegra/drm.c:961: * If the host1x client is already attached to an IOMMU domain that is > drivers/gpu/drm/tegra/drm.c-962- * not the shared IOMMU domain, don't try to attach it to a different > drivers/gpu/drm/tegra/drm.c-963- * domain. This allows using the IOMMU-backed DMA API. > drivers/gpu/drm/tegra/drm.c-964- */ > drivers/gpu/drm/tegra/drm.c-965- if (domain && domain->type != IOMMU_DOMAIN_IDENTITY && > drivers/gpu/drm/tegra/drm.c-966- domain != tegra->domain) > > So, the check is two-fold: > 1) is attached > 2) is the shared IOMMU domain (tegra->domain?) Yea iommu_is_domain_currently_attached(dev, tegra->domain) > Overall, I feel this would be a big project yet arguably for a low > reward.. Indeed, we can drop a FIXME comment there and leave it as the last user or something perhaps Jason
