On Thu, Nov 19, 2020 at 9:41 AM Thierry Reding <[email protected]> wrote: > > From: Thierry Reding <[email protected]> > > Commit d0511b5496c0 ("firmware: QCOM_SCM: Allow qcom_scm driver to be > loadable as a permenent module") causes the ARM SMMU driver to be built > as a loadable module when using the Aarch64 default configuration. This > in turn causes problems because if the loadable module is not shipped > in an initial ramdisk, then the deferred probe timeout mechanism will > cause all SMMU masters to probe without SMMU support and fall back to > just plain DMA ops (not IOMMU-backed). > > Once the system has mounted the rootfs, the ARM SMMU driver will then > be loaded, but since the ARM SMMU driver faults by default, this causes > a slew of SMMU faults for the SMMU masters that have already been set > up with plain DMA ops and cause these devices to malfunction. > > Revert that commit to unbreak things while we look for an alternative > solution. > > Reported-by: Jon Hunter <[email protected]> > Signed-off-by: Thierry Reding <[email protected]>
Acked-by: John Stultz <[email protected]> Thanks for sending this Thierry, and sorry again for the troubles. thanks -john _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
