Re: [v6 04/15] mm: discard memblock data later

Michal Hocko
2017-08-11T16:04:41Z

On Fri 11-08-17 11:49:15, Pasha Tatashin wrote:
> >I guess this goes all the way down to
> >Fixes: 7e18adb4f80b ("mm: meminit: initialise remaining struct pages in parallel with kswapd")
>
> I will add this to the patch.
>
> >>Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
> >>Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
> >>Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
> >>Reviewed-by: Bob Picco <bob.picco@oracle.com>
> >
> >Considering that some HW might behave strangely and this would be rather
> >hard to debug I would be tempted to mark this for stable. It should also
> >be merged separately from the rest of the series.
> >
> >I have just one nit below
> >Acked-by: Michal Hocko <mhocko@suse.com>
>
> I will address your comment, and send out a new patch. Should I send it out
> separately from the series or should I keep it inside?

I would post it separatelly. It doesn't depend on the rest.

> Also, before I send out a new patch, I will need to root cause and resolve
> problem found by kernel test robot <fengguang.wu@intel.com>, and bisected
> down to this patch.
>
> [ 156.659400] BUG: Bad page state in process swapper pfn:03147
> [ 156.660051] page:ffff88001ed8a1c0 count:0 mapcount:-127 mapping:
> (null) index:0x1
> [ 156.660917] flags: 0x0()
> [ 156.661198] raw: 0000000000000000 0000000000000000 0000000000000001
> 00000000ffffff80
> [ 156.662006] raw: ffff88001f4a8120 ffff88001ed85ce0 0000000000000000
> 0000000000000000
> [ 156.662811] page dumped because: nonzero mapcount
> [ 156.663307] CPU: 0 PID: 1 Comm: swapper Not tainted
> 4.13.0-rc3-00220-g1aad694 #1
> [ 156.664077] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> 1.9.3-20161025_171302-gandalf 04/01/2014
> [ 156.665129] Call Trace:
> [ 156.665422] dump_stack+0x1e/0x20
> [ 156.665802] bad_page+0x122/0x148

Was the report related with this patch?
--
Michal Hocko
SUSE Labs