On arm64 with 64K page , I observed the following test failure: ... subtest_dmabuf_iter_check_lots_of_buffers:FAIL:total_bytes_read unexpected total_bytes_read: actual 4696 <= expected 65536 #97/3 dmabuf_iter/lots_of_buffers:FAIL With 4K page on x86, the total_bytes_read is 4593. With 64K page on arm64, the total_byte_read is 4696. In progs/dmabuf_iter.c, for each iteration, the output is BPF_SEQ_PRINTF(seq, "%lu\n%llu\n%s\n%s\n", inode, size, name, exporter); The only difference between 4K and 64K page is 'size' in the above BPF_SEQ_PRINTF. The 4K page will output '4096' and the 64K page will output '65536'. So the total_bytes_read with 64K page is slighter greater than 4K page. Adjusting the total_bytes_read from 65536 to 4096 fixed the issue. Cc: T.J. Mercier Signed-off-by: Yonghong Song --- tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c b/tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c index e442be9dde7e..fb2cea710db3 100644 --- a/tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/dmabuf_iter.c @@ -233,7 +233,7 @@ static void subtest_dmabuf_iter_check_lots_of_buffers(struct dmabuf_iter *skel) while ((bytes_read = read(iter_fd, buf, sizeof(buf))) > 0) total_bytes_read += bytes_read; - ASSERT_GT(total_bytes_read, getpagesize(), "total_bytes_read"); + ASSERT_GT(total_bytes_read, 4096, "total_bytes_read"); close(iter_fd); } -- 2.47.3