> >> --- > >> drivers/hv/hv_balloon.c | 14 ++++++++++++-- > >> 1 file changed, 12 insertions(+), 2 deletions(-) > >> > >> diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c > >> index 211f3fe3a038..47719862e57f 100644 > >> --- a/drivers/hv/hv_balloon.c > >> +++ b/drivers/hv/hv_balloon.c > >> @@ -681,8 +681,13 @@ static struct notifier_block hv_memory_nb = { > >> /* Check if the particular page is backed and can be onlined and online > >> it. > >> */ > >> static void hv_page_online_one(struct hv_hotadd_state *has, struct page > >> *pg) > >> { > >> - if (!has_pfn_is_backed(has, page_to_pfn(pg))) > >> + if (!has_pfn_is_backed(has, page_to_pfn(pg))) { > >> + if (!PageOffline(pg)) > >> + __SetPageOffline(pg); > >> return; > >> + } > >> + if (PageOffline(pg)) > >> + __ClearPageOffline(pg); > >> > >> /* This frame is currently backed; online the page. */ > >> __online_page_set_limits(pg); > >> @@ -1201,6 +1206,7 @@ static void free_balloon_pages(struct > >> hv_dynmem_device > >> *dm, > >> > >> for (i = 0; i < num_pages; i++) { > >> pg = pfn_to_page(i + start_frame); > >> + __ClearPageOffline(pg); > > > > Just thinking, do we need to care for clearing PageOffline flag before > > freeing > > a balloon'd page? > > Yes we have to otherwise the code will crash when trying to set PageBuddy. > > (only one page type at a time may be set right now, and it makes sense. > A page that is offline cannot e.g. be a buddy page) o.k > > So PageOffline is completely managed by the page owner. Makes sense. Thanks for explaining. Pankaj > > > > > Thanks, > > Pankaj > > > -- > > Thanks, > > David / dhildenb >