From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> [ Upstream commit c56cba5daf45d2d091ef1cfe2f1d6a930446687b ] Intel IOMMU could be turned off with intel_iommu=off. If Intel IOMMU is off, the intel_iommu struct will not be initialized. When device drivers call intel_svm_bind_mm(), the NULL pointer reference will happen there. Add dmar_disabled check to avoid NULL pointer reference. Cc: Ashok Raj <ashok.raj@xxxxxxxxx> Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> Reported-by: Dave Jiang <dave.jiang@xxxxxxxxx> Fixes: 2f26e0a9c9860 ("iommu/vt-d: Add basic SVM PASID support") Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/iommu/intel-svm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index 188f4eaed6e59..fd8730b2cd46e 100644 --- a/drivers/iommu/intel-svm.c +++ b/drivers/iommu/intel-svm.c @@ -293,7 +293,7 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ int pasid_max; int ret; - if (!iommu) + if (!iommu || dmar_disabled) return -EINVAL; if (dev_is_pci(dev)) { -- 2.20.1