On Wed, Sep 18, 2024 at 02:34:57PM +0100, Matthew Wilcox wrote: > On Wed, Sep 18, 2024 at 11:28:52AM +0200, Chris Mason wrote: > > I think the bug was in __filemap_add_folio()'s usage of xarray_split_alloc() > > and the tree changing before taking the lock. It's just a guess, but that > > was always my biggest suspect. > > Oh god, that's it. > > there should have been an xas_reset() after calling xas_split_alloc(). > > and 6758c1128ceb calls xas_reset() after calling xas_split_alloc(). Should we be asking for 6758c1128ceb to be backported to all stable kernels then? -Dave. -- Dave Chinner david@xxxxxxxxxxxxx