From 8bbd9f04b7d982d1c6aeb5c08f5983b3d0b9e2fe Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 19 Jun 2013 12:04:26 +0530 Subject: [PATCH] powerpc: Fix bad pmd error with book3E config Book3E uses the hugepd at PMD level and don't encode pte directly at the pmd level. So it will find the lower bits of pmd set and the pmd_bad check throws error. Infact the current code will never take the free_hugepd_range call at all because it will clear the pmd if it find a hugepd pointer. Fix this by clearing bad pmd only if it is not a hugepd pointer. This is regression introduced by e2b3d202d1dba8f3546ed28224ce485bc50010be "powerpc: Switch 16GB and 16MB explicit hugepages to a different page table format" Reported-by: Scott Wood Signed-off-by: Aneesh Kumar K.V Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/mm/hugetlbpage.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c index 237c8e5f2640..77fdd2cef33b 100644 --- a/arch/powerpc/mm/hugetlbpage.c +++ b/arch/powerpc/mm/hugetlbpage.c @@ -592,8 +592,14 @@ static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud, do { pmd = pmd_offset(pud, addr); next = pmd_addr_end(addr, end); - if (pmd_none_or_clear_bad(pmd)) + if (!is_hugepd(pmd)) { + /* + * if it is not hugepd pointer, we should already find + * it cleared. + */ + WARN_ON(!pmd_none_or_clear_bad(pmd)); continue; + } #ifdef CONFIG_PPC_FSL_BOOK3E /* * Increment next by the size of the huge mapping since