[LTP] [PATCH v6 1/1] thp04: Add ptrace mode and fix tracee stop synchronization

[Jan Polensky]

On Fri, Jul 10, 2026 at 02:02:04PM +0200, Cyril Hrubis wrote:
> Hi!
> > That's a fair point.
> >
> > The main goal was to keep thp04 functional on kernels with
> > CONFIG_PROC_MEM_FORCE_PTRACE=y, where direct writes via /proc/self/mem
> > are no longer possible.
> >
> > Do you have a preference for how support for that configuration should
> > look?
> >
> > Would you prefer:
> >
> >   1. Keeping thp04 focused on the original race test and skipping it
> >      when only ptrace-based writes are available?
> >
> >   2. Splitting the ptrace write validation into a separate testcase and
> >      leaving thp04 unchanged?
> >
> >   3. Some other approach?
>
> 1 + 2 please.
>
> The thp04 is a CVE regression test, if there is no chance to trigger the
> CVE it should just report TCONF.
>
>
> > I'm mostly trying to understand the intended coverage for
> > CONFIG_PROC_MEM_FORCE_PTRACE=y before making further changes.
>
> For that we should add tests under testcases/syscalls/ptrace/. I suppose
> that we need a test that would check that the process cannot modify
> itself when that config option is enabled. And another test that would
> validate that parent can access child memory.
>
> --
> Cyril Hrubis
> chrubis@suse.cz
Hi Cyril,

thanks, I followed your suggestion and posted a new series:
https://lore.kernel.org/all/20260714150631.250972-1-japo@linux.ibm.com/

Best regards,
Jan