uffd_test_ctx_clear() is being called from uffd_test_ctx_init() to unmap
areas used in the previous test run.  This approach is problematic because
while unmapping areas uffd_test_ctx_clear() uses page_size and nr_pages
which might differ from one test run to another.  Fix this by calling
uffd_test_ctx_clear() after each test is done.
Link: https://lkml.kernel.org/r/20231206103702.3873743-4-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Nicolas Geoffray <ngeoffray@google.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: ZhangPeng <zhangpeng362@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
 
        *area = NULL;
 }
 
-static void uffd_test_ctx_clear(void)
+void uffd_test_ctx_clear(void)
 {
        size_t i;
 
        unsigned long nr, cpu;
        int ret;
 
-       uffd_test_ctx_clear();
-
        ret = uffd_test_ops->allocate_area((void **)&area_src, true);
        ret |= uffd_test_ops->allocate_area((void **)&area_dst, false);
        if (ret) {
 
 
 void uffd_stats_report(struct uffd_args *args, int n_cpus);
 int uffd_test_ctx_init(uint64_t features, const char **errmsg);
+void uffd_test_ctx_clear(void);
 int userfaultfd_open(uint64_t *features);
 int uffd_read_msg(int ufd, struct uffd_msg *msg);
 void wp_range(int ufd, __u64 start, __u64 len, bool wp);
 
                uffd_stats_reset(args, nr_cpus);
 
                /* bounce pass */
-               if (stress(args))
+               if (stress(args)) {
+                       uffd_test_ctx_clear();
                        return 1;
+               }
 
                /* Clear all the write protections if there is any */
                if (test_uffdio_wp)
 
                uffd_stats_report(args, nr_cpus);
        }
+       uffd_test_ctx_clear();
 
        return 0;
 }
 
                                continue;
                        }
                        test->uffd_fn(&args);
+                       uffd_test_ctx_clear();
                }
        }