From b4e789075ee9e80652ce3a9758f10d09bbafc614 Mon Sep 17 00:00:00 2001 From: Chris Metcalf Date: Thu, 29 Mar 2012 15:36:53 -0400 Subject: [PATCH] arch/tile: don't set the homecache of a PTE unless appropriate We make sure not to try to set the home for an MMIO PTE (on tilegx) or a PTE that isn't referencing memory managed by Linux. Signed-off-by: Chris Metcalf --- arch/tile/mm/pgtable.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/arch/tile/mm/pgtable.c b/arch/tile/mm/pgtable.c index 14e7e9e53e34..277645f182ff 100644 --- a/arch/tile/mm/pgtable.c +++ b/arch/tile/mm/pgtable.c @@ -467,10 +467,18 @@ void __set_pte(pte_t *ptep, pte_t pte) void set_pte(pte_t *ptep, pte_t pte) { - struct page *page = pfn_to_page(pte_pfn(pte)); - - /* Update the home of a PTE if necessary */ - pte = pte_set_home(pte, page_home(page)); + if (pte_present(pte) && + (!CHIP_HAS_MMIO() || hv_pte_get_mode(pte) != HV_PTE_MODE_MMIO)) { + /* The PTE actually references physical memory. */ + unsigned long pfn = pte_pfn(pte); + if (pfn_valid(pfn)) { + /* Update the home of the PTE from the struct page. */ + pte = pte_set_home(pte, page_home(pfn_to_page(pfn))); + } else if (hv_pte_get_mode(pte) == 0) { + /* remap_pfn_range(), etc, must supply PTE mode. */ + panic("set_pte(): out-of-range PFN and mode 0\n"); + } + } __set_pte(ptep, pte); } -- 2.39.5