Commit 78a523fe authored Mar 02, 2021 by Jacob Pan Committed by Joerg Roedel Mar 18, 2021

iommu/vt-d: Reject unsupported page request modes



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: 1c4f88b7 ("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@linux.intel.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>

parent bb0f6153

drivers/iommu/intel/svm.c

+11 −1

Original line number	Diff line number	Diff line
		@@ -920,7 +920,17 @@ 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);