From: Jacob Pan jacob.jun.pan@linux.intel.com
[ Upstream commit 78a523fe73b81b4447beb2d6c78c9fafae24eebb ]
When supervisor/privilige mode SVM is used, we bind init_mm.pgd with a supervisor PASID. There should not be any page fault for init_mm. Execution request with DMA read is also not supported.
This patch checks PRQ descriptor for both unsupported configurations, reject them both with invalid responses.
Fixes: 1c4f88b7f1f92 ("iommu/vt-d: Shared virtual address in scalable mode") Acked-by: Lu Baolu baolu.lu@linux.intel.com Signed-off-by: Jacob Pan jacob.jun.pan@linux.intel.com Link: https://lore.kernel.org/r/1614680040-1989-4-git-send-email-jacob.jun.pan@lin... Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/intel/svm.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index b200a3acc6ed..5c95e9693bf5 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -959,7 +959,17 @@ static irqreturn_t prq_event_thread(int irq, void *d) ((unsigned long long *)req)[1]); goto no_pasid; } - + /* We shall not receive page request for supervisor SVM */ + if (req->pm_req && (req->rd_req | req->wr_req)) { + pr_err("Unexpected page request in Privilege Mode"); + /* No need to find the matching sdev as for bad_req */ + goto no_pasid; + } + /* DMA read with exec requeset is not supported. */ + if (req->exe_req && req->rd_req) { + pr_err("Execution request not supported\n"); + goto no_pasid; + } if (!svm || svm->pasid != req->pasid) { rcu_read_lock(); svm = ioasid_find(NULL, req->pasid, NULL);