diff options
| -rw-r--r-- | arch/arm/Kconfig.debug | 12 | ||||
| -rw-r--r-- | arch/arm/include/asm/cacheflush.h | 9 |
2 files changed, 21 insertions, 0 deletions
diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug index 815018770fb9..553b02b31847 100644 --- a/arch/arm/Kconfig.debug +++ b/arch/arm/Kconfig.debug @@ -86,6 +86,18 @@ config FORCE_PAGES If unsure say N. +config FREE_PAGES_RDONLY + bool "Set pages as read only while on the buddy list" + select FORCE_PAGES + select PAGE_POISONING + help + Pages are always mapped in the kernel. This means that anyone + can write to the page if they have the address. Enable this option + to mark pages as read only to trigger a fault if any code attempts + to write to a page on the buddy list. This may have a performance + impact. + + If unsure, say N. # These options are only for real kernel hackers who want to get their hands dirty. config DEBUG_LL diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h index 2005a47b491e..2e2d1657e604 100644 --- a/arch/arm/include/asm/cacheflush.h +++ b/arch/arm/include/asm/cacheflush.h @@ -539,4 +539,13 @@ static inline void secure_flush_area(const void *addr, size_t size) outer_flush_range(phys, phys + size); } +#ifdef CONFIG_FREE_PAGES_RDONLY +#define mark_addr_rdonly(a) set_memory_ro((unsigned long)a, 1) +#define mark_addr_rdwrite(a) set_memory_rw((unsigned long)a, 1) +#else +#define mark_addr_rdonly(a) +#define mark_addr_rdwrite(a) +#endif + + #endif |