There appears to be a kernel config item CONFIG_X86_X32:
http://cateee.net/lkddb/web-lkddb/X86_X32.html
You can try checking
/boot/config-$(uname -r)
To see if there's any information there, but on my RHEL6.7 system, that
string does not appear -- but I surely have 32-bit ABI support in the
kernel.
--
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Robert Jacobson Robert.C.Jacobson(a)nasa.gov
Lead System Admin Solar Dynamics Observatory (SDO)
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