Right now, if we have two isolations racing, we might trigger the WARN_ON_ONCE() and to dump_page(NULL), dereferencing NULL. Let's just return directly. In the future, we might want to report -EAGAIN to the caller instead, as this could indicate a temporary isolation failure only. Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Michael S. Tsirkin <mst@xxxxxxxxxx> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> --- mm/page_isolation.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/mm/page_isolation.c b/mm/page_isolation.c index f6d07c5f0d34d..553b49a34cf71 100644 --- a/mm/page_isolation.c +++ b/mm/page_isolation.c @@ -29,10 +29,12 @@ static int set_migratetype_isolate(struct page *page, int migratetype, int isol_ /* * We assume the caller intended to SET migrate type to isolate. * If it is already set, then someone else must have raced and - * set it before us. Return -EBUSY + * set it before us. */ - if (is_migrate_isolate_page(page)) - goto out; + if (is_migrate_isolate_page(page)) { + spin_unlock_irqrestore(&zone->lock, flags); + return -EBUSY; + } /* * FIXME: Now, memory hotplug doesn't call shrink_slab() by itself. -- 2.26.2 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization