Re: [QUESTION] xfs, iomap: Handle writeback errors to prevent silent data corruption

[Christoph Hellwig <hch@infradead.org>]

On Tue, Jun 03, 2025 at 07:35:23AM -0700, Darrick J. Wong wrote:
> On Sun, Jun 01, 2025 at 10:32:33PM -0700, Christoph Hellwig wrote:
> > On Wed, May 28, 2025 at 09:25:50PM -0700, Darrick J. Wong wrote:
> > > Option C: report all those write errors (direct and buffered) to a
> > > daemon and let it figure out what it wants to do:
> > 
> > What value does the daemon add to the decision chain?
> 
> The decision chain itself is unchanged -- the events are added to a
> queue (if kmalloc doesn't fail) for later distribution to userspace...
> 
> > Some form of out of band error reporting is good and extremely useful,
> > but having it in the critical error handling path is not.
> 
> ...and the error handling path moves on without waiting to see what
> happens to the queued events.  Once the daemon picks up the event it
> can decide what to do with it, but that's totally asynchronous from the
> IO path.

Yes, I'm fully on board with that.  Maybe I just misinterpreted earlier
mails.