[PATCH] selftests/mm: Fixed incorrect buffer->mirror size in hmm2 double_map test

[Donet Tom]

The hmm2 double_map test was failing due to an incorrect
buffer->mirror size. The buffer->mirror size was 6, while buffer->ptr
size was 6 * PAGE_SIZE. The test failed because the kernel's
copy_to_user function was attempting to copy a 6 * PAGE_SIZE buffer
to buffer->mirror. Since the size of buffer->mirror was incorrect,
copy_to_user failed.

This patch corrects the buffer->mirror size to 6 * PAGE_SIZE.

Test Result without this patch
==============================
 #  RUN           hmm2.hmm2_device_private.double_map ...
 # hmm-tests.c:1680:double_map:Expected ret (-14) == 0 (0)
 # double_map: Test terminated by assertion
 #          FAIL  hmm2.hmm2_device_private.double_map
 not ok 53 hmm2.hmm2_device_private.double_map

Test Result with this patch
===========================
 #  RUN           hmm2.hmm2_device_private.double_map ...
 #            OK  hmm2.hmm2_device_private.double_map
 ok 53 hmm2.hmm2_device_private.double_map

Signed-off-by: Donet Tom <donet...@linux.ibm.com>
---
 tools/testing/selftests/mm/hmm-tests.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/mm/hmm-tests.c 
b/tools/testing/selftests/mm/hmm-tests.c
index d2cfc9b494a0..141bf63cbe05 100644
--- a/tools/testing/selftests/mm/hmm-tests.c
+++ b/tools/testing/selftests/mm/hmm-tests.c
@@ -1657,7 +1657,7 @@ TEST_F(hmm2, double_map)
 
        buffer->fd = -1;
        buffer->size = size;
-       buffer->mirror = malloc(npages);
+       buffer->mirror = malloc(size);
        ASSERT_NE(buffer->mirror, NULL);
 
        /* Reserve a range of addresses. */
-- 
2.43.5