diff options
| -rw-r--r-- | arch/x86/mm/pageattr.c | 35 |
1 files changed, 31 insertions, 4 deletions
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 877b5cca2cb..bf5e33f6a32 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -106,6 +106,22 @@ static void cpa_flush_range(unsigned long start, int numpages) } } +#define HIGH_MAP_START __START_KERNEL_map +#define HIGH_MAP_END (__START_KERNEL_map + KERNEL_TEXT_SIZE) + + +/* + * Converts a virtual address to a X86-64 highmap address + */ +static unsigned long virt_to_highmap(void *address) +{ +#ifdef CONFIG_X86_64 + return __pa((unsigned long)address) + HIGH_MAP_START - phys_base; +#else + return (unsigned long)address; +#endif +} + /* * Certain areas of memory on x86 require very specific protection flags, * for example the BIOS area or kernel text. Callers don't always get this @@ -129,12 +145,24 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address) */ if (within(address, (unsigned long)_text, (unsigned long)_etext)) pgprot_val(forbidden) |= _PAGE_NX; + /* + * Do the same for the x86-64 high kernel mapping + */ + if (within(address, virt_to_highmap(_text), virt_to_highmap(_etext))) + pgprot_val(forbidden) |= _PAGE_NX; + #ifdef CONFIG_DEBUG_RODATA /* The .rodata section needs to be read-only */ if (within(address, (unsigned long)__start_rodata, (unsigned long)__end_rodata)) pgprot_val(forbidden) |= _PAGE_RW; + /* + * Do the same for the x86-64 high kernel mapping + */ + if (within(address, virt_to_highmap(__start_rodata), + virt_to_highmap(__end_rodata))) + pgprot_val(forbidden) |= _PAGE_RW; #endif prot = __pgprot(pgprot_val(prot) & ~pgprot_val(forbidden)); @@ -304,8 +332,6 @@ 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, @@ -338,10 +364,11 @@ change_page_attr_addr(unsigned long address, pgprot_t mask_set, /* * Calc the high mapping address. See __phys_addr() * for the non obvious details. + * + * Note that NX and other required permissions are + * checked in static_protections(). */ 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, because we check |