Re: [PATCH v2 00/33] iommu: Move iommu_group setup to IOMMU core code

[Jerry Snitselaar]

On Fri May 29 20, Jerry Snitselaar wrote:
> On Tue Apr 14 20, Joerg Roedel wrote:
> > Hi,
> >
> > here is the second version of this patch-set. The first version with
> > some more introductory text can be found here:
> >
> > 	https://lore.kernel.org/lkml/20200407183742.4344-1-joro@xxxxxxxxxx/
> >
> > Changes v1->v2:
> >
> > 	* Rebased to v5.7-rc1
> >
> > 	* Re-wrote the arm-smmu changes as suggested by Robin Murphy
> >
> > 	* Re-worked the Exynos patches to hopefully not break the
> > 	  driver anymore
> >
> > 	* Fixed a missing mutex_unlock() reported by Marek Szyprowski,
> > 	  thanks for that.
> >
> > There is also a git-branch available with these patches applied:
> >
> > 	https://git.kernel.org/pub/scm/linux/kernel/git/joro/linux.git/log/?h=iommu-probe-device-v2
> >
> > Please review.
> >
> > Thanks,
> >
> > 	Joerg
> >
> > Joerg Roedel (32):
> > iommu: Move default domain allocation to separate function
> > iommu/amd: Implement iommu_ops->def_domain_type call-back
> > iommu/vt-d: Wire up iommu_ops->def_domain_type
> > iommu/amd: Remove dma_mask check from check_device()
> > iommu/amd: Return -ENODEV in add_device when device is not handled by
> >   IOMMU
> > iommu: Add probe_device() and remove_device() call-backs
> > iommu: Move default domain allocation to iommu_probe_device()
> > iommu: Keep a list of allocated groups in __iommu_probe_device()
> > iommu: Move new probe_device path to separate function
> > iommu: Split off default domain allocation from group assignment
> > iommu: Move iommu_group_create_direct_mappings() out of
> >   iommu_group_add_device()
> > iommu: Export bus_iommu_probe() and make is safe for re-probing
> > iommu/amd: Remove dev_data->passthrough
> > iommu/amd: Convert to probe/release_device() call-backs
> > iommu/vt-d: Convert to probe/release_device() call-backs
> > iommu/arm-smmu: Convert to probe/release_device() call-backs
> > iommu/pamu: Convert to probe/release_device() call-backs
> > iommu/s390: Convert to probe/release_device() call-backs
> > iommu/virtio: Convert to probe/release_device() call-backs
> > iommu/msm: Convert to probe/release_device() call-backs
> > iommu/mediatek: Convert to probe/release_device() call-backs
> > iommu/mediatek-v1 Convert to probe/release_device() call-backs
> > iommu/qcom: Convert to probe/release_device() call-backs
> > iommu/rockchip: Convert to probe/release_device() call-backs
> > iommu/tegra: Convert to probe/release_device() call-backs
> > iommu/renesas: Convert to probe/release_device() call-backs
> > iommu/omap: Remove orphan_dev tracking
> > iommu/omap: Convert to probe/release_device() call-backs
> > iommu/exynos: Use first SYSMMU in controllers list for IOMMU core
> > iommu/exynos: Convert to probe/release_device() call-backs
> > iommu: Remove add_device()/remove_device() code-paths
> > iommu: Unexport iommu_group_get_for_dev()
> >
> > Sai Praneeth Prakhya (1):
> > iommu: Add def_domain_type() callback in iommu_ops
> >
> > drivers/iommu/amd_iommu.c       |  97 ++++----
> > drivers/iommu/amd_iommu_types.h |   1 -
> > drivers/iommu/arm-smmu-v3.c     |  38 +--
> > drivers/iommu/arm-smmu.c        |  39 ++--
> > drivers/iommu/exynos-iommu.c    |  24 +-
> > drivers/iommu/fsl_pamu_domain.c |  22 +-
> > drivers/iommu/intel-iommu.c     |  68 +-----
> > drivers/iommu/iommu.c           | 393 +++++++++++++++++++++++++-------
> > drivers/iommu/ipmmu-vmsa.c      |  60 ++---
> > drivers/iommu/msm_iommu.c       |  34 +--
> > drivers/iommu/mtk_iommu.c       |  24 +-
> > drivers/iommu/mtk_iommu_v1.c    |  50 ++--
> > drivers/iommu/omap-iommu.c      |  99 ++------
> > drivers/iommu/qcom_iommu.c      |  24 +-
> > drivers/iommu/rockchip-iommu.c  |  26 +--
> > drivers/iommu/s390-iommu.c      |  22 +-
> > drivers/iommu/tegra-gart.c      |  24 +-
> > drivers/iommu/tegra-smmu.c      |  31 +--
> > drivers/iommu/virtio-iommu.c    |  41 +---
> > include/linux/iommu.h           |  21 +-
> > 20 files changed, 533 insertions(+), 605 deletions(-)
> >
> > --
> > 2.17.1
> >
> > _______________________________________________
> > iommu mailing list
> > iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
> > https://lists.linuxfoundation.org/mailman/listinfo/iommu
>
> Hi Joerg,
>
> With this patchset, I have an epyc system where if I boot with
> iommu=nopt and force a dump I will see some io page faults for a nic
> on the system. The vmcore is harvested and the system reboots. I
> haven't reproduced it on other systems yet, but without the patchset I
> don't see the io page faults during the kdump.
>
> Regards,
> Jerry

I just hit an issue on a separate intel based system (kdump iommu=nopt),
where it panics in during intel_iommu_attach_device, in is_aux_domain,
due to device_domain_info being DEFER_DEVICE_DOMAIN_INFO. That doesn't
get set to a valid address until the domain_add_dev_info call.

Is it as simple as the following?

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 29d3940847d3..f1bbeed46a4c 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -5053,8 +5053,8 @@ is_aux_domain(struct device *dev, struct iommu_domain *domain)
 {
        struct device_domain_info *info = dev->archdata.iommu;
 
-       return info && info->auxd_enabled &&
-                       domain->type == IOMMU_DOMAIN_UNMANAGED;
+       return info && info != DEFER_DEVICE_DOMAIN_INFO &&
+               info->auxd_enabled && domain->type == IOMMU_DOMAIN_UNMANAGED;
 }
 
 static void auxiliary_link_device(struct dmar_domain *domain,


Regards,
Jerry