This mini-series adds an explicit test that verifies a page fault will occur for attempts to write to an r/o page while CR0.WP=1. There are existing tests already, e.g. in pks.c, pku.c, smap.c or even access.c that implicitly test it as well. However, they all either explicitly (via INVLPG) or implicitly (via CR3 reload) flush the TLB before such an access which might lead to false positives if the access succeeded before, e.g. because CR0.WP was 0 before. Better to have an explicit test, especially to back up the changes of [1]. Please apply! Thanks, Mathias [1] https://lore.kernel.org/kvm/20230322013731.102955-1-minipli@xxxxxxxxxxxxxx/ Mathias Krause (2): x86: Use existing CR0.WP / CR4.SMEP bit definitions x86/access: CR0.WP toggling write access test x86/access.c | 57 +++++++++++++++++++++++++++++++++++++++++++--------- x86/pks.c | 5 ++--- x86/pku.c | 5 ++--- 3 files changed, 52 insertions(+), 15 deletions(-) -- 2.39.2
