On Thu, May 04, 2023 at 05:07:10PM +0200, Ilya Dryomov wrote: > On Thu, May 4, 2023 at 4:16 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote: > > I hate both of these patches ;-) What we should do is add > > AS_STABLE_WRITES, have the appropriate places call > > mapping_set_stable_writes() and then folio_wait_stable() becomes > > > > if (mapping_test_stable_writes(folio->mapping)) > > folio_wait_writeback(folio); > > > > and we remove all the dereferences (mapping->host->i_sb->s_iflags, plus > > whatever else is going on there) > > Hi Matthew, > > We would still need something resembling Christoph's suggestion for > 5.10 and 5.15 (at least). Since this fixes a regression, would you > support merging the "ugly" version to facilitate backports or would > you rather see the AS/mapping-based refactor first? That's a terrible way of developing for Linux. First, do it the right way for mainline. Then, see how easy the patch is to backport to relevant kernel versions; if it's too ugly to cherry-pick, do something equivalent. But never start out with the premise "This must be backported, so do it as simply as possible first".