Re: [PATCH v3] selftests/mm: Fix ARM related issue with fork after pthread_create

[Andrew Morton]

On Mon, 25 Mar 2024 19:40:52 +0000 Edward Liaw <edliaw@xxxxxxxxxx> wrote:

> Following issue was observed while running the uffd-unit-tests selftest
> on ARM devices. On x86_64 no issues were detected:
> 
> pthread_create followed by fork caused deadlock in certain cases
> wherein fork required some work to be completed by the created thread.
> Used synchronization to ensure that created thread's start function has
> started before invoking fork.

hm, you cc'ed the whole world apart from peterx.  Fixed.

> Signed-off-by: Lokesh Gidra <lokeshgidra@xxxxxxxxxx>
> [edliaw: Refactored to use atomic_bool]
> Signed-off-by: Edward Liaw <edliaw@xxxxxxxxxx>

I'll add cc:stable.  For which a Fixes: is desirable.  I used
760aee0b71e3 ("selftests/mm: add tests for RO pinning vs fork()"),
please check that.