[PARISC] Add CONFIG_DEBUG_RODATA to protect read-only data

Add the parisc version of the "mark rodata section read only" patches.
Based on code from and Signed-off-by Arjan van de Ven
<arjan@infradead.org>, Ingo Molnar <mingo@elte.hu>, Andi Kleen <ak@muc.de>,
Andrew Morton <akpm@osdl.org>, Linus Torvalds <torvalds@osdl.org>.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
diff --git a/arch/parisc/Kconfig.debug b/arch/parisc/Kconfig.debug
index 8caaed1..9166bd1 100644
--- a/arch/parisc/Kconfig.debug
+++ b/arch/parisc/Kconfig.debug
@@ -11,4 +11,14 @@
           too many attempts.  If you suspect a rwlock problem or a kernel
           hacker asks for this option then say Y.  Otherwise say N.
 
+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 TLB anymore.
+         If in doubt, say "N".
+
 endmenu