thp: khugepaged_prealloc_page() forgot to reset the page alloc indicator

If NUMA is enabled, the indicator is not reset if the previous page
request failed, ausing us to trigger the BUG_ON() in
khugepaged_alloc_page().

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 2b2019b35b8d7c5435e684d1c22bde75dd53dff3..7ef62d5ce967a39839614ed411530ee323e2b7c6 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1882,6 +1882,7 @@ static bool khugepaged_prealloc_page(struct page **hpage, bool *wait)
                        return false;
 
                *wait = false;
+               *hpage = NULL;
                khugepaged_alloc_sleep();
        } else if (*hpage) {
                put_page(*hpage);