On 11 March 2015 at 18:30, Andrew Jones <drjo...@redhat.com> wrote: > My interpretation of SCTLR_EL1.WXN was just wrong. There is > talks about "EL1&0"
That's just the name of the translation regime (ie there's a shared set of page tables that handle translation for both EL1 and EL0). > and I assumed it meant that when WXN is > on, then both EL1 and EL0 should lose executability. No; and you can see an example of this in the table: UXN=0, PXN=0, AP[2:1] = 00, WXN=0 is RWX for EL1 and X for EL0. Setting WXN changes the EL1 rights to just RW (because the page is writable there) but leaves the EL0 rights as X (because there the page is not writable). > However > it can certainly be interpreted as applying to them both, but > based on their respective access permissions, which is how > I guess I should have interpreted it. Yes, this is the correct interpretation. -- PMM
