diff options
| author | Joerg Roedel <jroedel@suse.de> | 2020-05-19 15:03:40 +0200 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2020-05-19 15:05:43 +0200 |
| commit | bd421264ed307dd296eab036851221b225071a32 (patch) | |
| tree | 61927cf6cef2607118ec52d79611abd56354039e | |
| parent | ea90228c7b2ae6646bb6381385229aabb6f14cd2 (diff) | |
iommu: Fix deferred domain attachment
The IOMMU core code has support for deferring the attachment of a domain
to a device. This is needed in kdump kernels where the new domain must
not be attached to a device before the device driver takes it over.
When the AMD IOMMU driver got converted to use the dma-iommu
implementation, the deferred attaching got lost. The code in
dma-iommu.c has support for deferred attaching, but it calls into
iommu_attach_device() to actually do it. But iommu_attach_device()
will check if the device should be deferred in it code-path and do
nothing, breaking deferred attachment.
Move the is_deferred_attach() check out of the attach_device path and
into iommu_group_add_device() to make deferred attaching work from the
dma-iommu code.
Fixes: 795bbbb9b6f8 ("iommu/dma-iommu: Handle deferred devices")
Reported-by: Jerry Snitselaar <jsnitsel@redhat.com>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: Tom Murphy <murphyt7@tcd.ie>
Cc: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20200519130340.14564-1-joro@8bytes.org
| -rw-r--r-- | drivers/iommu/iommu.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 7b375421afba..1faa08c8bbb4 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -693,6 +693,15 @@ out: return ret; } +static bool iommu_is_attach_deferred(struct iommu_domain *domain, + struct device *dev) +{ + if (domain->ops->is_attach_deferred) + return domain->ops->is_attach_deferred(domain, dev); + + return false; +} + /** * iommu_group_add_device - add a device to an iommu group * @group: the group into which to add the device (reference should be held) @@ -747,7 +756,7 @@ rename: mutex_lock(&group->mutex); list_add_tail(&device->list, &group->devices); - if (group->domain) + if (group->domain && !iommu_is_attach_deferred(group->domain, dev)) ret = __iommu_attach_device(group->domain, dev); mutex_unlock(&group->mutex); if (ret) @@ -1653,9 +1662,6 @@ static int __iommu_attach_device(struct iommu_domain *domain, struct device *dev) { int ret; - if ((domain->ops->is_attach_deferred != NULL) && - domain->ops->is_attach_deferred(domain, dev)) - return 0; if (unlikely(domain->ops->attach_dev == NULL)) return -ENODEV; @@ -1727,8 +1733,7 @@ EXPORT_SYMBOL_GPL(iommu_sva_unbind_gpasid); static void __iommu_detach_device(struct iommu_domain *domain, struct device *dev) { - if ((domain->ops->is_attach_deferred != NULL) && - domain->ops->is_attach_deferred(domain, dev)) + if (iommu_is_attach_deferred(domain, dev)) return; if (unlikely(domain->ops->detach_dev == NULL)) |