diff options
Diffstat (limited to 'lib/test_user_copy.c')
| -rw-r--r-- | lib/test_user_copy.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/lib/test_user_copy.c b/lib/test_user_copy.c index ad2372727b1b..5ff04d8fe971 100644 --- a/lib/test_user_copy.c +++ b/lib/test_user_copy.c @@ -47,9 +47,25 @@ static bool is_zeroed(void *from, size_t size) static int test_check_nonzero_user(char *kmem, char __user *umem, size_t size) { int ret = 0; - size_t start, end, i; - size_t zero_start = size / 4; - size_t zero_end = size - zero_start; + size_t start, end, i, zero_start, zero_end; + + if (test(size < 2 * PAGE_SIZE, "buffer too small")) + return -EINVAL; + + /* + * We want to cross a page boundary to exercise the code more + * effectively. We also don't want to make the size we scan too large, + * otherwise the test can take a long time and cause soft lockups. So + * scan a 1024 byte region across the page boundary. + */ + size = 1024; + start = PAGE_SIZE - (size / 2); + + kmem += start; + umem += start; + + zero_start = size / 4; + zero_end = size - zero_start; /* * We conduct a series of check_nonzero_user() tests on a block of |