iommu/amd: Take mmap_sem when calling get_user_pages

[linux-2.6-microblaze.git] / drivers / iommu / amd_iommu_v2.c

diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c
index 5208828..203b2e6 100644 (file)
--- a/drivers/iommu/amd_iommu_v2.c
+++ b/drivers/iommu/amd_iommu_v2.c
@@ -504,8 +504,10 @@ static void do_fault(struct work_struct *work)
 
        write = !!(fault->flags & PPR_FAULT_WRITE);
 
+       down_read(&fault->state->mm->mmap_sem);
        npages = get_user_pages(fault->state->task, fault->state->mm,
                                fault->address, 1, write, 0, &page, NULL);
+       up_read(&fault->state->mm->mmap_sem);
 
        if (npages == 1) {
                put_page(page);