Someone setting NX on the kernel text tends to result in nasty failures
and triple faults, so BUG_ON early for that.

Does not cover __inittext.

Signed-off-by: Andi Kleen <[EMAIL PROTECTED]>

---
 arch/x86/mm/pageattr_32.c |    8 ++++++++
 1 file changed, 8 insertions(+)

Index: linux/arch/x86/mm/pageattr_32.c
===================================================================
--- linux.orig/arch/x86/mm/pageattr_32.c
+++ linux/arch/x86/mm/pageattr_32.c
@@ -242,6 +242,14 @@ __change_page_attr(struct page *page, pg
        BUG_ON(PageLRU(kpte_page));
        BUG_ON(PageCompound(kpte_page));
 
+       /*
+        * Better fail early if someone sets the kernel text to NX.
+        * Does not cover __inittext
+        */
+       BUG_ON(address >= (unsigned long)&_text &&
+               address < (unsigned long)&_etext &&
+              (pgprot_val(prot) & _PAGE_NX));
+
        set_tlb_flush(address, cache_attr_changed(*kpte, prot, level),
                        level < 3);
 
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