On Tue, Feb 26, 2019 at 1:57 PM Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > On Mon, Feb 25, 2019 at 10:41 PM Nikolaus Rath <Nikolaus@xxxxxxxx> wrote: > > > > On Feb 12 2019, Nikolaus Rath <Nikolaus@xxxxxxxx> wrote: > > > On Feb 12 2019, Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > >> On Sun, Feb 10, 2019 at 11:05 PM Nikolaus Rath <Nikolaus@xxxxxxxx> wrote: > > >> > > >>> Bad news. I can now reliably reproduce the issue again. > > >> > > >> A reliable reproducer is always good news. Are the messages exactly > > >> the same as last time (value of flags, etc)? > > > > > > The flags, count, mapcount and mapping values are always the same. The > > > page and index is varying. So the general format is: > > > > > > [ 2562.773181] fuse: trying to steal weird page > > > [ 2562.773187] page=<something> index=<something> > > > flags=17ffffc00000ad, count=1, mapcount=0, mapping= (null) > > > > Is there anything else I can do to help debugging this? > > Could you please try the attached patch? Looking more, it's very unlikely to help. remove_mapping() should already ensure that the page count is 1. I think this bug report needs to be forwarded to the <linux-mm@xxxxxxxxx> mailing list as this appears to be a race somewhere in the memory management subsystem and fuse is only making it visible due to its sanity checking in the page stealing code. Thanks, Miklos
