From a686425b31bb6441f6e20d698bf31dc65043f61f Mon Sep 17 00:00:00 2001 From: Gerald Schaefer Date: Wed, 9 May 2012 16:27:37 +0200 Subject: [PATCH] s390/hugepages: clear page table for sw large page emulation The software large page emulation on s390 did not clear the the pre-allocated page table in arch_release_hugepage() before freeing it. This could trigger the WARN_ON(!pte_none(*pte) in mm/vmalloc.c:106 and make vmap_pte_range() fail, because the page table could be reused in page_table_alloc(). This is fixed now by calling clear_table() before page_table_free(). Signed-off-by: Gerald Schaefer Signed-off-by: Martin Schwidefsky --- arch/s390/mm/hugetlbpage.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/s390/mm/hugetlbpage.c b/arch/s390/mm/hugetlbpage.c index 597bb2d27c3c..900de2b3cf28 100644 --- a/arch/s390/mm/hugetlbpage.c +++ b/arch/s390/mm/hugetlbpage.c @@ -58,6 +58,8 @@ void arch_release_hugepage(struct page *page) ptep = (pte_t *) page[1].index; if (!ptep) return; + clear_table((unsigned long *) ptep, _PAGE_TYPE_EMPTY, + PTRS_PER_PTE * sizeof(pte_t)); page_table_free(&init_mm, (unsigned long *) ptep); page[1].index = 0; }