Re: [PATCH v1 2/2] fs/writeback: skip inodes with potential writeback hang in wait_sb_inodes()

[Miklos Szeredi <miklos@szeredi.hu>]

On Wed, 26 Nov 2025 at 18:58, Joanne Koong <joannelkoong@gmail.com> wrote:
>
> On Wed, Nov 26, 2025 at 2:55 AM David Hildenbrand (Red Hat)
> <david@kernel.org> wrote:
> > >
> > >> having a flag that states something like that that
> > >> "AS_NO_WRITEBACK_WAIT_ON_DATA_SYNC" would probable be what we would want
> > >> to add to avoid waiting for writeback with clear semantics why it is ok
> > >> in that specific scenario.
> > >
> > > Having a separate AS_NO_WRITEBACK_WAIT_ON_DATA_SYNC mapping flag
> > > sounds reasonable to me and I agree is more clearer semantically.
> >
> > Good. Then it's clear that we are not waiting because writeback is
> > shaky, but because even if it would be working, because we don't have to
> > because there are no such guarantees.
> >
> > Maybe
> >
> > AS_NO_DATA_INTEGRITY
> >
> > or similar would be cleaner, I'll have to leave that to you and Miklos
> > to decide what exactly the semantics are that fuse currently doesn't
> > provide.
>
> After reading Miklos's reply, I must have misunderstood this then - my
> understanding was that the reason we couldn't guarantee data integrity
> in fuse was because of the temp pages design where checking the
> writeback flag on the real folio doesn't reflect writeback state, but
> that removing the temp pages and using the real folio now does
> guarantee this. But it seems like it's not as simple as that and
> there's no data integrity guarantees for other reasons.
>
> Changing this to AS_NO_DATA_INTEGRITY sounds good to me, if that
> sounds good to Miklos as well. Or do you have another preference,
> Miklos?

Sure, sounds good.

(Sorry about the delay, missed this.)

Thanks,
Miklos