Re: pmap attempts at copying to executable pages both on mips and powerpc/booke

On 2016/09/28 20:40, Nick Hudson wrote:
> The problem is here...
>
> https://nxr.netbsd.org/xref/src/sys/uvm/pmap/pmap.c#1275
>
>    1275     if (pte_valid_p(opte) && pte_to_paddr(opte) != pa) {
>    1276         pmap_remove(pmap, va, va + NBPG);
>    1277         PMAP_COUNT(user_mappings_changed);
>    1278     }
>    1279
>    1280     KASSERT(pte_valid_p(npte));
>    1281     const bool resident = pte_valid_p(opte);
>    1282     if (resident) {
>    1283         update_flags |= PMAP_TLB_NEED_IPI;
>    1284     } else {
>    1285         pmap->pm_stats.resident_count++;
>    1286     }
>
> if the mapping changes PA then the resident_count gets reduced by pmap_{,pte_}remove, but not increased again.
>
> I'm working on a fix.

Thank you very much for your analysis. I'm looking forward to hearing
good news from you!

Rin