On 6/1/26 10:44, Lance Yang wrote: > > > On 2026/6/1 16:15, David Hildenbrand (Arm) wrote: >> On 6/1/26 09:49, Lance Yang wrote: >>> >>> >>> >>> I had Codex do the boring grep-work through the arch update_mmu_cache* >>> code :D >>> >>> MIPS doesn't seem to be the only code doing a re-walk, but it is the >>> only one I found that appears to assume the PMD/PTE walk cannot fail, >>> without checking whether the PMD is none ... >> >> Okay, but likely the other code that tries to handle it is also problematic. >> >> Best to make sure the page table is already installed when updating the >> entries. > > Neat, makes sense to me :D > > That way the page talbe is back in place before any arch hook gets to look at > it :)
Right. I don't think we could run into a deadlock here (nobody should concurrently take a look at the page tables in the first place). Not sure about the memory barrier I dropped: the page tables are already properly set up (just some entries cleared), so I'd assume that barrier might not be required. -- Cheers, David
