> > Oh god - my eyes are bleeding after reading those excerpts. That's > > sad, especially since (according to Wikipedia) the Loongsoon has > > on-chip circuitry to help resist buffer overflow attacks - seems a wee > > bit counter-productive. > > AKA it supports execute/no execute permissions, like probably every > mips chip made in the last 20 years.
No, execute (or lack of) permission is quite an alien concept to mips chips. The Loongson 2E documentation nevertheless documents a specific NX bit to set in TLB entries to get non-executable pages (i.e. to only load the TLB in the DTLB and not in the ITLB), but the documentation is ambiguous and never mentions what exception will fire if attempting to execute code from this page. All mention of this has disappeared in the 2F documentation, so I'm not even sure this feature is still available. But I'm not surprised marketing people still brag about it (-: Miod
