RDMA/i40w: Hold read semaphore while looking after VMA

VMA lookup is supposed to be performed while mmap_sem is held.

Fixes: f26c7c83395b ("i40iw: Add 2MB page support")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/hw/i40iw/i40iw_verbs.c b/drivers/infiniband/hw/i40iw/i40iw_verbs.c
index 8884ff71a63468aceb78ee8774752f2a5cf3283c..7d85414742ff6a3f4f375ae9d57b8cf8ba2ccbdf 100644 (file)
--- a/drivers/infiniband/hw/i40iw/i40iw_verbs.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_verbs.c
@@ -1410,6 +1410,7 @@ static void i40iw_set_hugetlb_values(u64 addr, struct i40iw_mr *iwmr)
        struct vm_area_struct *vma;
        struct hstate *h;
 
+       down_read(&current->mm->mmap_sem);
        vma = find_vma(current->mm, addr);
        if (vma && is_vm_hugetlb_page(vma)) {
                h = hstate_vma(vma);
@@ -1418,6 +1419,7 @@ static void i40iw_set_hugetlb_values(u64 addr, struct i40iw_mr *iwmr)
                        iwmr->page_msk = huge_page_mask(h);
                }
        }
+       up_read(&current->mm->mmap_sem);
 }
 
 /**