Re: [PATCH v3 0/5] selftests/mm: skip several tests when thp is not available

[Chunyu Hu <chuhu@redhat.com>]

On Tue, Mar 17, 2026 at 11:37:30AM -0700, Andrew Morton wrote:
> On Tue, 17 Mar 2026 17:44:14 +0800 Chunyu Hu <chuhu@redhat.com> wrote:
> 
> > There are several tests requires transprarent hugepages, when run on thp
> > disabled kernel such as realtime kernel, there will be false negative.
> > Mark those tests as skip when thp is not available.
> 
> AI review asked some questions:
> https://sashiko.dev/#/patchset/20260317094419.1429259-1-chuhu%40redhat.com

Hi Andrew,

Nice tool.
 
For question one. In guard-region test, collapse tests are for checking
collapse is denied when operating on guard region, not for checking
madvise(MADV_COLLAPSE) will fail when thp is setup to 'never with sysfs,
result is same, but it's a different test. Maybe we don't have strong
interest to test when thp is set to 'never' in this collapse test.
Do you perfer we let it run when thp is setup with 'never'?

For question two. In soft dirty test. Yes, test_mprotect skip logic has
similar issue when open failed. 'Bail out' would be shown. Maybe we
do this in other series or you prefer me to fix it in this series?

For question three. Add buffer length check in write_file() helper and
check if written bytes equal expected bytes. It's easy to add a buffer
lenghth check and make it robust. It's not easy to do the partial
written check as that will make the helper more complex and need one
more parameter as expected written bytes. Maybe for such question, we
should do with other series, not in this one?

Thanks!