Messages in this thread Patch in this message | | | From | Laura Abbott <> | Subject | [PATCH 1/2] arm64: Get existing page protections in split_pmd | Date | Tue, 3 Nov 2015 13:48:34 -0800 |
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Rather than always putting the least restrictived permissions (PAGE_KERNEL_EXEC) when spliting a pmd into pages, use the existing permissions from the pmd for the page.
Signed-off-by: Laura Abbott <labbott@fedoraproject.org> --- arch/arm64/mm/mmu.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 9211b85..ff41efa 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -75,14 +75,13 @@ static void __init *early_alloc(unsigned long sz) static void split_pmd(pmd_t *pmd, pte_t *pte) { unsigned long pfn = pmd_pfn(*pmd); + unsigned long addr = pfn << PAGE_SHIFT; + pgprot_t prot = __pgprot(pmd_val(*pmd) ^ addr) | PTE_TYPE_PAGE; + int i = 0; do { - /* - * Need to have the least restrictive permissions available - * permissions will be fixed up later - */ - set_pte(pte, pfn_pte(pfn, PAGE_KERNEL_EXEC)); + set_pte(pte, pfn_pte(pfn, prot)); pfn++; } while (pte++, i++, i < PTRS_PER_PTE); } -- 2.4.3
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