It looks safe to do unlock/relock mmap_sem in the middle of shmat(), so
passing "false" here.

Signed-off-by: Yang Shi <yang....@linux.alibaba.com>
---
 ipc/shm.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/ipc/shm.c b/ipc/shm.c
index 4643865..1617523 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -1537,7 +1537,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg,
                         */
                        file = vma->vm_file;
                        size = i_size_read(file_inode(vma->vm_file));
-                       do_munmap(mm, vma->vm_start, vma->vm_end - 
vma->vm_start, NULL);
+                       do_munmap(mm, vma->vm_start, vma->vm_end - 
vma->vm_start,
+                                 NULL, false);
                        /*
                         * We discovered the size of the shm segment, so
                         * break out of here and fall through to the next
@@ -1564,7 +1565,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg,
                if ((vma->vm_ops == &shm_vm_ops) &&
                    ((vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) &&
                    (vma->vm_file == file))
-                       do_munmap(mm, vma->vm_start, vma->vm_end - 
vma->vm_start, NULL);
+                       do_munmap(mm, vma->vm_start, vma->vm_end - 
vma->vm_start,
+                                 NULL, false);
                vma = next;
        }
 
@@ -1573,7 +1575,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg,
         * given
         */
        if (vma && vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) {
-               do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL);
+               do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start,
+                         NULL, false);
                retval = 0;
        }
 
-- 
1.8.3.1

Reply via email to