diff options
| -rw-r--r-- | arch/x86/mm/pageattr.c | 56 |
1 files changed, 30 insertions, 26 deletions
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 532a40bc0e7..ec07c1873d6 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -305,49 +305,53 @@ repeat: * Modules and drivers should use the set_memory_* APIs instead. */ +#define HIGH_MAP_START __START_KERNEL_map +#define HIGH_MAP_END (__START_KERNEL_map + KERNEL_TEXT_SIZE) + static int change_page_attr_addr(unsigned long address, pgprot_t mask_set, - pgprot_t mask_clr) + pgprot_t mask_clr) { - int err = 0, kernel_map = 0; - unsigned long pfn; + unsigned long phys_addr = __pa(address); + unsigned long pfn = phys_addr >> PAGE_SHIFT; + int err; #ifdef CONFIG_X86_64 - if (address >= __START_KERNEL_map && - address < __START_KERNEL_map + KERNEL_TEXT_SIZE) { - - address = (unsigned long)__va(__pa((void *)address)); - kernel_map = 1; - } + /* + * If we are inside the high mapped kernel range, then we + * fixup the low mapping first. __va() returns the virtual + * address in the linear mapping: + */ + if (within(address, HIGH_MAP_START, HIGH_MAP_END)) + address = (unsigned long) __va(phys_addr); #endif - pfn = __pa(address) >> PAGE_SHIFT; - - if (!kernel_map || 1) { - err = __change_page_attr(address, pfn, mask_set, mask_clr); - if (err) - return err; - } + err = __change_page_attr(address, pfn, mask_set, mask_clr); + if (err) + return err; #ifdef CONFIG_X86_64 /* - * Handle kernel mapping too which aliases part of - * lowmem: + * If the physical address is inside the kernel map, we need + * to touch the high mapped kernel as well: */ - if (__pa(address) < KERNEL_TEXT_SIZE) { - unsigned long addr2; - - addr2 = __pa(address) + __START_KERNEL_map - phys_base; + if (within(phys_addr, 0, KERNEL_TEXT_SIZE)) { + /* + * Calc the high mapping address. See __phys_addr() + * for the non obvious details. + */ + address = phys_addr + HIGH_MAP_START - phys_base; /* Make sure the kernel mappings stay executable */ pgprot_val(mask_clr) |= _PAGE_NX; + /* - * Our high aliases are imprecise, so do not propagate - * failures back to users: + * Our high aliases are imprecise, because we check + * everything between 0 and KERNEL_TEXT_SIZE, so do + * not propagate lookup failures back to users: */ - __change_page_attr(addr2, pfn, mask_set, mask_clr); + __change_page_attr(address, pfn, mask_set, mask_clr); } #endif - return err; } |