On Wed, May 14, 2025 at 10:42:53AM +0200, Vlastimil Babka wrote: > On 5/14/25 10:40, Lorenzo Stoakes wrote: > > Having encountered a trinity report in linux-next (Linked in the 'Closes' > > tag) it appears that there are legitimate situations where a file-backed > > mapping can be acquired but no file->f_op->mmap or file->f_op->mmap_prepare > > is set, at which point do_mmap() should simply error out with -ENODEV. > > > > Since previously we did not warn in this scenario and it appears we rely > > upon this, restore this situation, while retaining a WARN_ON_ONCE() for the > > case where both are set, which is absolutely incorrect and must be > > addressed and thus always requires a warning. > > > > If further work is required to chase down precisely what is causing this, > > then we can later restore this, but it makes no sense to hold up this > > series to do so, as this is existing and apparently expected behaviour. > > > > Reported-by: kernel test robot <oliver.sang@xxxxxxxxx> > > Closes: https://lore.kernel.org/oe-lkp/202505141434.96ce5e5d-lkp@xxxxxxxxx > > Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> > > Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx> Reviewed-by: Pedro Falcato <pfalcato@xxxxxxx> -- Pedro
