Re: [PATCH v7 00/12] Support non-lru page migration

[Sergey Senozhatsky]

On (06/16/16 15:47), Minchan Kim wrote:
> > [..]
> > > > this is what I'm getting with the [zsmalloc: keep first object offset in struct page]
> > > > applied:  "count:0 mapcount:-127". which may be not related to zsmalloc at this point.
> > > > 
> > > > kernel: BUG: Bad page state in process khugepaged  pfn:101db8
> > > > kernel: page:ffffea0004076e00 count:0 mapcount:-127 mapping:          (null) index:0x1
> > > 
> > > Hm, it seems double free.
> > > 
> > > It doen't happen if you disable zram? IOW, it seems to be related
> > > zsmalloc migration?
> > 
> > need to test more, can't confidently answer now.
> > 
> > > How easy can you reprodcue it? Could you bisect it?
> > 
> > it takes some (um.. random) time to trigger the bug.
> > I'll try to come up with more details.
> 
> Could you revert [1] and retest?
> 
> [1] mm/compaction: split freepages without holding the zone lock

ok, so this is not related to zsmalloc. finally manged to reproduce
it. will fork a separate thread.

	-ss