Messages in this thread Patch in this message | | | From | Laura Abbott <> | Subject | [PATCHv2 1/2] arm64: Get existing page protections in split_pmd | Date | Tue, 10 Nov 2015 17:57:36 -0800 |
| |
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> --- v2: Typo and typechecking fixed
I chose not to add the Reviewed-by from Ard here because of the addition of the contiguous bit in split_pmd. Not sure if I should be explicitly carrying it over. --- arch/arm64/mm/mmu.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index c2fa6b5..496c3fd 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -76,15 +76,13 @@ 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. Default the new page - * range as contiguous ptes. - */ - set_pte(pte, pfn_pte(pfn, PAGE_KERNEL_EXEC_CONT)); + set_pte(pte, pfn_pte(pfn, prot)); pfn++; } while (pte++, i++, i < PTRS_PER_PTE); } -- 2.5.0
| |