On 02.12.20 17:12, Vitaly Kuznetsov wrote: > Unlike virtio_balloon/virtio_mem/xen balloon drivers, Hyper-V balloon driver > does not adjust managed pages count when ballooning/un-ballooning and this > leads > to incorrect stats being reported, e.g. unexpected 'free' output. > > Note, the calculation in post_status() seems to remain correct: ballooned out > pages are never 'available' and we manually add dm->num_pages_ballooned to > 'commited'. > > Suggested-by: David Hildenbrand <[email protected]> > Signed-off-by: Vitaly Kuznetsov <[email protected]> > --- > drivers/hv/hv_balloon.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c > index da3b6bd2367c..8c471823a5af 100644 > --- a/drivers/hv/hv_balloon.c > +++ b/drivers/hv/hv_balloon.c > @@ -1198,6 +1198,7 @@ static void free_balloon_pages(struct hv_dynmem_device > *dm, > __ClearPageOffline(pg); > __free_page(pg); > dm->num_pages_ballooned--; > + adjust_managed_page_count(pg, 1); > } > } > > @@ -1238,8 +1239,10 @@ static unsigned int alloc_balloon_pages(struct > hv_dynmem_device *dm, > split_page(pg, get_order(alloc_unit << PAGE_SHIFT)); > > /* mark all pages offline */ > - for (j = 0; j < alloc_unit; j++) > + for (j = 0; j < alloc_unit; j++) { > __SetPageOffline(pg + j); > + adjust_managed_page_count(pg + j, -1); > + } > > bl_resp->range_count++; > bl_resp->range_array[i].finfo.start_page = >
I assume this has been properly tested such that it does not change the system behavior regarding when/how HyperV decides to add/remove memory. LGTM Reviewed-by: David Hildenbrand <[email protected]> -- Thanks, David / dhildenb
