On 22/05/2020 14:04, Jan Beulich wrote: > On 22.05.2020 13:11, Roger Pau Monné wrote: >> That being said, I also don't like the fact that logdity is handled >> differently between EPT and NPT, as on EPT it's handled as a >> misconfig while on NPT it's handled as a violation. > Because, well, there is no concept of misconfig in NPT.
Indeed. Intel chose to split EPT errors into two - MISCONFIG for structural errors (not present, or reserved bits set) and VIOLATION for permissions errors. AMD reused the same silicon pagewalker design, so have a single NPT_FAULT vmexit which behaves much more like a regular pagefault, encoding structural vs permission errors in the error code. ~Andrew
