This SMM-specific patch fixes something different, the bug that you are still
hitting is the FNAME(cmpxchg_gpte) mess. The uaccess CMPXCHG series[*] that
properly fixes that issue hasn't been merged yet.
==================================================================
BUG: KASAN: use-after-free in ept_cmpxchg_gpte.constprop.0+0x3c3/0x590
Write of size 8 at addr ffff888010000000 by task repro/5633
[*]https://lore.kernel.org/all/20220202004945.2540433-1-seanjc@xxxxxxxxxx