Red Hat builds of OpenJDK ship with some patches to remove the implementation of Elliptic Curves, for example:

https://pkgs.devel.redhat.com/cgit/rpms/java-1.8.0-openjdk/tree/generate_source_tarball.sh?h=rhel-8.7.0#n135

https://pkgs.devel.redhat.com/cgit/rpms/java-11-openjdk/tree/generate_source_tarball.sh?h=rhel-8.7.0#n143

https://pkgs.devel.redhat.com/cgit/rpms/java-17-openjdk/tree/generate_source_tarball.sh?h=rhel-8.4.0#n148

https://github.com/icedtea-git/icedtea/blob/12.0/patches/pr3823.patch

https://github.com/icedtea-git/icedtea/blob/6.0/patches/gh001-4curve.patch

https://github.com/icedtea-git/icedtea/blob/3.0/patches/pr3822-4curve.patch

And similar.

These patched were added for historical reasons:

https://fedoraproject.org/wiki/Legal:ECC

But upon assessment, the code as implemented in OpenJDK now is consistently licensed under GPLv2+CE and unencumbered, and we believe that license is actually relevant in this context and can remove the patches.