On Sat, Aug 21, 2021 at 05:42:46PM +0800, Miaohe Lin wrote: > HWPoisoned dirty swapcache pages are kept for killing owner processes. > We should not offline these pages or do_swap_page() would access the > offline pages and lead to bad ending. > Thank you for the report. I'm not yet sure of the whole picture of this issue. do_swap_page() is expected to return with fault VM_FAULT_HWPOISON when called via the access to the error page, so I wonder why this doesn't work for your situation. And what is the "bad ending" in the description? I feel that aborting memory hotremove due to a hwpoisoned dirty swapcache might be too hard, so I'd like to find another solution if we have. # You may separate this patch from former two to make them merged to # mainline soon. Thanks, Naoya Horiguchi > Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> > --- > mm/memory_hotplug.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 9fd0be32a281..0488eed3327c 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1664,6 +1664,12 @@ static int scan_movable_pages(unsigned long start, unsigned long end, > */ > if (PageOffline(page) && page_count(page)) > return -EBUSY; > + /* > + * HWPoisoned dirty swapcache pages are definitely unmovable > + * because they are kept for killing owner processes. > + */ > + if (PageHWPoison(page) && PageSwapCache(page)) > + return -EBUSY;
