[PATCH v4 02/16] iommu/amd: Handle race between registration and device probe

From: Robin Murphy
Date: Mon Aug 15 2022 - 12:20:37 EST


As for the Intel driver, make sure the AMD driver can cope with seeing
.probe_device calls without having to wait for all known instances to
register first.

Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
---

v4: No change

drivers/iommu/amd/iommu.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 65b8e4fd8217..5ed9fd40d2a7 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -1851,6 +1851,10 @@ static struct iommu_device *amd_iommu_probe_device(struct device *dev)
if (!iommu)
return ERR_PTR(-ENODEV);

+ /* Not registered yet? */
+ if (!iommu->iommu.ops)
+ return ERR_PTR(-ENODEV);
+
if (dev_iommu_priv_get(dev))
return &iommu->iommu;

--
2.36.1.dirty