diff options
Diffstat (limited to 'arch/x86_64/mm/pageattr.c')
| -rw-r--r-- | arch/x86_64/mm/pageattr.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/arch/x86_64/mm/pageattr.c b/arch/x86_64/mm/pageattr.c index 081409aa3452..d653d0bf3df6 100644 --- a/arch/x86_64/mm/pageattr.c +++ b/arch/x86_64/mm/pageattr.c @@ -180,16 +180,24 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot, */ int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot) { - int err = 0; + int err = 0, kernel_map = 0; int i; + if (address >= __START_KERNEL_map + && address < __START_KERNEL_map + KERNEL_TEXT_SIZE) { + address = (unsigned long)__va(__pa(address)); + kernel_map = 1; + } + down_write(&init_mm.mmap_sem); for (i = 0; i < numpages; i++, address += PAGE_SIZE) { unsigned long pfn = __pa(address) >> PAGE_SHIFT; - err = __change_page_attr(address, pfn, prot, PAGE_KERNEL); - if (err) - break; + if (!kernel_map || pte_present(pfn_pte(0, prot))) { + err = __change_page_attr(address, pfn, prot, PAGE_KERNEL); + if (err) + break; + } /* Handle kernel mapping too which aliases part of the * lowmem */ if (__pa(address) < KERNEL_TEXT_SIZE) { |