On Mon, Mar 10, 2014 at 10:01:58PM -0700, Andrew Morton wrote:
> On Tue, 11 Mar 2014 00:51:09 -0400 Dave Jones <davej@xxxxxxxxxx> wrote:
>
> > On Mon, Mar 10, 2014 at 09:46:12PM -0700, Andrew Morton wrote:
> > > On Mon, 10 Mar 2014 20:13:40 -0700 Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > > > Anyone ? I'm hitting this trace on an almost daily basis, which is a pain
> > > > > while trying to reproduce a different bug..
> > > >
> > > > Damn, I thought we'd fixed that but it seems not. Cc's added.
> > > >
> > > > Guys, what stops the migration target page from coming unlocked in
> > > > parallel with zap_pte_range()'s call to migration_entry_to_page()?
> > >
> > > page_table_lock, sort-of. At least, transitions of is_migration_entry()
> > > and page_locked() happen under ptl.
> > >
> > > I don't see any holes in regular migration. Do you know if this is
> > > reproducible with CONFIG_NUMA_BALANCING=n or CONFIG_NUMA=n?
> >
> > CONFIG_NUMA_BALANCING was n already btw, so I'll do a NUMA=n run.
>
> There probably isn't much point unless trinity is using
> sys_move_pages(). Is it? If so it would be interesting to disable
> trinity's move_pages calls and see if it still fails.
Ok, with move_pages excluded it still oopses.