In RHEL 9 we should review the amount of L3 used for in-flight memory copies and adjust based on upstream discussions with Intel.

The same issue for RHEL 8 is this one:
https://bugzilla.redhat.com/show_bug.cgi?id=2180462

In particular, this should include a backport of this commit to benefit TDX environments as they exist today:

commit ed2f9dc9420c4c61436328778a70459d0a35556a
Author: Noah Goldstein <goldstein.w.n>
Date:   Mon May 8 22:10:20 2023 -0500

    x86: Use 64MB as nt-store threshold if no cacheinfo [BZ #30429]
    
    If `non_temporal_threshold` is below `minimum_non_temporal_threshold`,
    it almost certainly means we failed to read the systems cache info.
    
    In this case, rather than defaulting the minimum correct value, we
    should default to a value that gets at least reasonable
    performance. 64MB is chosen conservatively to be at the very high
    end. This should never cause non-temporal stores when, if we had read
    cache info, we wouldn't have otherwise.
    Reviewed-by: Florian Weimer <fweimer>