iommu_sva_bind_device requires that iommu_dev_enable_feature has been previously called with IOMMU_DEV_FEAT_SVA, and succeeded. Without this it is possible to run into a situation where you will dereference a null pointer if the intel_iommu driver is not enabled. Note: checkpatch didn't like the suggested addition of braces for the first arm of the "if (idxd_enable_system_pasid)" block. Fixes: 42a1b73852c4 ("dmaengine: idxd: Separate user and kernel pasid enabling") Cc: Vinod Koul <vkoul@xxxxxxxxxx> Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: Dave Jiang <dave.jiang@xxxxxxxxx> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> Signed-off-by: Jerry Snitselaar <jsnitsel@xxxxxxxxxx> --- drivers/dma/idxd/init.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index 355fb3ef4cbf..5b49fd5c1e25 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -514,13 +514,14 @@ static int idxd_probe(struct idxd_device *idxd) if (IS_ENABLED(CONFIG_INTEL_IDXD_SVM) && sva) { if (iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA)) dev_warn(dev, "Unable to turn on user SVA feature.\n"); - else + else { set_bit(IDXD_FLAG_USER_PASID_ENABLED, &idxd->flags); - if (idxd_enable_system_pasid(idxd)) - dev_warn(dev, "No in-kernel DMA with PASID.\n"); - else - set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); + if (idxd_enable_system_pasid(idxd)) + dev_warn(dev, "No in-kernel DMA with PASID.\n"); + else + set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); + } } else if (!sva) { dev_warn(dev, "User forced SVA off via module param.\n"); } -- 2.36.1