On Thu, Jun 16, 2016 at 07:09:32PM +0900, Minchan Kim wrote: > On Thu, Jun 16, 2016 at 05:42:11PM +0900, Sergey Senozhatsky wrote: > > 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. > > The reason I mentioned [1] is that it seems to have a bug. > > isolate_freepages_block > __isolate_free_page > if(!zone_watermark_ok()) > return 0; > list_add_tail(&page->lru, freelist); > > However, the page is not isolated. > Joonsoo? Good job! I will fix it soon. Thanks. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>