On Tue, Jun 25, 2024 at 11:25 AM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Sat, 22 Jun 2024 15:20:02 +1200 Barry Song <21cnbao@xxxxxxxxx> wrote: > > > > > > > > > Since this is primarily a documentation update, I'll wait for two or > > > > three days to see if > > > > there are any more Linux-next reports before sending v3 combining these fixes > > > > together(I've already fixed another doc warn reported by lkp) and seek Andrew's > > > > assistance to drop v2 and apply v3. > > > > > > Feel free to send fixup patches for such small stuff (for example, as > > > reply to this mail). Usually, no need for a new series. Andrew will > > > squash all fixups before merging it to mm-stable. > > > > Hi Andrew, > > > > Can you please squash this change(another one suggested by David)? > > sure, but... > > > From: Barry Song <v-songbaohua@xxxxxxxx> > > Date: Sat, 22 Jun 2024 15:14:53 +1200 > > Subject: [PATCH] enhance doc- mm: use folio_add_new_anon_rmap() if > > folio_test_anon(folio)==false > > The only description we have here is "enhance doc" > > > --- a/mm/memory.c > > +++ b/mm/memory.c > > @@ -4346,6 +4346,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) > > * here, we have to be careful. > > */ > > VM_WARN_ON_ONCE(folio_test_large(folio)); > > + VM_WARN_ON_FOLIO(!folio_test_locked(folio), folio); > > And these aren't documentation changes. Please send along a small > changelog for this patch. Thanks for the suggestion. Could we have this in changelog? For new anon(!anon), there's a possibility that multiple concurrent threads might execute "if (!anon) folio_add_new_anon_rmap()" in parallel. In such cases, the threads should lock the folio before executing this sequence. We use VM_WARN_ON_FOLIO() to verify if this condition holds true. > Thanks Barry
