On 6/1/26 12:47, Lance Yang wrote: > > > On 2026/6/1 18:23, David Hildenbrand (Arm) wrote: >> On 6/1/26 11:08, Lance Yang wrote: >>> >>> >>> >>> One small thing, I think we should probably keep the smp_wmb(), and just >>> move it before the earlier pmd_populate(). >>> >>> IIUC, the ordering we want is still: >>> >>> clear old PTEs >>> smp_wmb() >>> pmd_populate() >>> >>> so another CPU cannot walk through the re-installed PMD and still observe >>> the old PTEs, right? >> >> There is a smp_wmb() in __folio_mark_uptodate(), that should be sufficient? > > Ah, cool! __folio_mark_uptodate() already does the job :P > > So yeah, no extra smp_wmb() needed here!
Yeah. BTW, I think we'd need a spin_lock_nested(), so @Nico, treat my code as a draft. -- Cheers, David
