diff options
| author | Jean-Philippe Brucker <jean-philippe@linaro.org> | 2021-04-22 11:42:19 +0200 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2021-05-18 11:18:39 +0200 |
| commit | d6177a6556f853785867e2ec6d5b7f4906f0d809 (patch) | |
| tree | 6b0ecf35dc715124138af2022dfc6f2535f76f61 /drivers/iommu/amd | |
| parent | d07f6ca923ea0927a1024dfccafc5b53b61cfecc (diff) | |
iommu/amd: Clear DMA ops when switching domain
Since commit 08a27c1c3ecf ("iommu: Add support to change default domain
of an iommu group") a user can switch a device between IOMMU and direct
DMA through sysfs. This doesn't work for AMD IOMMU at the moment because
dev->dma_ops is not cleared when switching from a DMA to an identity
IOMMU domain. The DMA layer thus attempts to use the dma-iommu ops on an
identity domain, causing an oops:
# echo 0000:00:05.0 > /sys/sys/bus/pci/drivers/e1000e/unbind
# echo identity > /sys/bus/pci/devices/0000:00:05.0/iommu_group/type
# echo 0000:00:05.0 > /sys/sys/bus/pci/drivers/e1000e/bind
...
BUG: kernel NULL pointer dereference, address: 0000000000000028
...
Call Trace:
iommu_dma_alloc
e1000e_setup_tx_resources
e1000e_open
Since iommu_change_dev_def_domain() calls probe_finalize() again, clear
the dma_ops there like Vt-d does.
Fixes: 08a27c1c3ecf ("iommu: Add support to change default domain of an iommu group")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Link: https://lore.kernel.org/r/20210422094216.2282097-1-jean-philippe@linaro.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/amd')
| -rw-r--r-- | drivers/iommu/amd/iommu.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 80e8e1916dd1..67da96d5b3c2 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -1714,6 +1714,8 @@ static void amd_iommu_probe_finalize(struct device *dev) domain = iommu_get_domain_for_dev(dev); if (domain->type == IOMMU_DOMAIN_DMA) iommu_setup_dma_ops(dev, IOVA_START_PFN << PAGE_SHIFT, 0); + else + set_dma_ops(dev, NULL); } static void amd_iommu_release_device(struct device *dev) |