On 23.02.2022 19:11, Tamas K Lengyel wrote: >> @@ -607,6 +607,7 @@ struct page_info *p2m_get_page_from_gfn( >> >> /* Error path: not a suitable GFN at all */ >> if ( !p2m_is_ram(*t) && !p2m_is_paging(*t) && !p2m_is_pod(*t) && >> + (!p2m_is_shared(*t) || !(q & P2M_UNSHARE)) && >> !mem_sharing_is_fork(p2m->domain) ) >> return NULL; >> } > > I don't follow what this is fixing. A shared entry would return true > to p2m_is_ram() - p2m_ram_shared is listed under P2M_RAM_TYPES - so > the rest of the if statement would never be checked. So if we get past > that check we know we definitely don't have a shared entry, ie > p2m_is_shared must be false ie the check for P2M_UNSHARE is dead code. > Am I missing something?
No, I am. I mistakenly took p2m_is_any_ram() to include the shared case, but p2m_is_ram() to not do so. Thanks for pointing out, and I'm actually happy to be able to droop this hunk. Jan
