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 Link: https://lkml.kernel.org/r/20240927050752.51066-1-donettom@xxxxxxxxxxxxx Fixes: fee9f6d1b8df ("mm/hmm/test: add selftests for HMM") Signed-off-by: Donet Tom <donettom@xxxxxxxxxxxxx> Reviewed-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx> Cc: Jérôme Glisse <jglisse@xxxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Mark Brown <broonie@xxxxxxxxxx> Cc: Przemek Kitszel <przemyslaw.kitszel@xxxxxxxxx> Cc: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Cc: Ralph Campbell <rcampbell@xxxxxxxxxx> Cc: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> 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. */
