On Sat, 26 Feb 2022, Hugh Dickins wrote: > > I say "often": it's very erratic. Once, a machine booted with mem=1G > ran kernel builds successfully swapping for 4.5 hours before faulting > in __nr_to_section in virt_to_folio ... while doing a __vma_adjust() - > you'll ask me for a full stacktrace, and I'll answer sorry, too many, > please try for yourself. Another time, for 1.5 hours before hitting > the BUG_ON(is_migration_entry(entry) && !PageLocked(p)) in > pfn_swap_entry_to_page() - suggesting anon_vma locking had not been > right while doing page migration (I was exercising THPs a lot). > But now, can I even get it to complete the boot sequence? Sorry, I never mentioned the architecture: x86_64 throughout for me.