On Mon, 28 Mar 2022 07:51:04 +0000, SJ wrote: > On Sun, 27 Mar 2022 16:03:45 +0800 Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx> wrote: > > > The bug is here: > > KUNIT_EXPECT_EQ(test, r->ar.start, start + i * expected_width); > > KUNIT_EXPECT_EQ(test, r->ar.end, end); > > > > For the damon_for_each_region(), just like list_for_each_entry(), > > the list iterator 'drm_crtc' will point to a bogus position > > containing HEAD if the list is empty or no element is found. > > This case must be checked before any use of the iterator, > > otherwise it will lead to a invalid memory access. > > We ensure 'damon_va_evenly_split_region()' successes before executing the loop, > so the issue cannot occur. That said, I think this patch makes code better to > read. Could you please resend this patch after fixing the commit message? Yes, you should be right. I have resend this patch with the commit message changed. Please check it, thank you. -- Xiaomeng Tong