An unidentified combination of speculative reads and branch predictions inside WRPROT-cacheable memory can cause invalidation of cachelines and loss of stack on models based on NetBurst microarchitecture. Therefore disable WRPROT region entirely for all family F models. As an extreme example, just changing the location of a constant string passed to printk() has been witnessed to make a the boot fail early on in romstage. Change-Id: I1df84ad55e2d8d6d4e8dca10125131b5f525f0d7 Signed-off-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-on: https://review.coreboot.org/27133 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>