iommu/vt-d: Calculate and set flags for handle_mm_fault

Page requests are originated from the user page fault. Therefore, we
shall set FAULT_FLAG_USER. 

FAULT_FLAG_REMOTE indicates that we are walking an mm which is not
guaranteed to be the same as the current->mm and should not be subject
to protection key enforcement. Therefore, we should set FAULT_FLAG_REMOTE
to avoid faults when both SVM and PKEY are used.

References: commit 1b2ee1266ea6 ("mm/core: Do not enforce PKEY permissions on remote mm access")
Reviewed-by: Raj Ashok <ashok.raj@intel.com>
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/1614680040-1989-5-git-send-email-jacob.jun.pan@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 4627437..54db589 100644 (file)
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -895,6 +895,7 @@ static irqreturn_t prq_event_thread(int irq, void *d)
        struct intel_iommu *iommu = d;
        struct intel_svm *svm = NULL;
        int head, tail, handled = 0;
+       unsigned int flags = 0;
 
        /* Clear PPR bit before reading head/tail registers, to
         * ensure that we get a new interrupt if needed. */
@@ -992,9 +993,11 @@ static irqreturn_t prq_event_thread(int irq, void *d)
                if (access_error(vma, req))
                        goto invalid;
 
-               ret = handle_mm_fault(vma, address,
-                                     req->wr_req ? FAULT_FLAG_WRITE : 0,
-                                     NULL);
+               flags = FAULT_FLAG_USER | FAULT_FLAG_REMOTE;
+               if (req->wr_req)
+                       flags |= FAULT_FLAG_WRITE;
+
+               ret = handle_mm_fault(vma, address, flags, NULL);
                if (ret & VM_FAULT_ERROR)
                        goto invalid;