[COMMITTED 2.40 1/2] nptl: initialize rseq area prior to registration

[Michael Jeanson]

On 2024-12-05 03:39, Florian Weimer wrote:
> * Michael Jeanson via Libc-stable:
> 
>> Per the rseq syscall documentation, 3 fields are required to be
>> initialized by userspace prior to registration, they are 'cpu_id',
>> 'rseq_cs' and 'flags'. Since we have no guarantee that 'struct pthread'
>> is cleared on all architectures, explicitly set those 3 fields prior to
>> registration.
>>
>> Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
>> Reviewed-by: Florian Weimer <fweimer@redhat.com>
>> (cherry picked from commit 97f60abd25628425971f07e9b0e7f8eec0741235)
> 
> Should we backport this further, maybe even to 2.35?

I checked and it does apply cleanly down to 2.35, I'll push those
backports as well.

Thanks,

Michael