[PATCH] x86/x86_64: mark rodata section read-only: x86-64 support

x86-64 specific parts to make the .rodata section read only

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/arch/x86_64/Kconfig.debug b/arch/x86_64/Kconfig.debug
index e2c6e64a85ec..fcb06a50fdd2 100644
--- a/arch/x86_64/Kconfig.debug
+++ b/arch/x86_64/Kconfig.debug
@@ -9,6 +9,16 @@ config INIT_DEBUG
           Fill __init and __initdata at the end of boot. This helps debugging
           illegal uses of __init and __initdata after initialization.
 
+config DEBUG_RODATA
+       bool "Write protect kernel read-only data structures"
+       depends on DEBUG_KERNEL
+       help
+         Mark the kernel read-only data as write-protected in the pagetables,
+         in order to catch accidental (and incorrect) writes to such const data.
+         This option may have a slight performance impact because a portion
+         of the kernel code won't be covered by a 2MB TLB anymore.
+         If in doubt, say "N".
+
 config IOMMU_DEBUG
        depends on GART_IOMMU && DEBUG_KERNEL
        bool "Enable IOMMU debugging"