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-rw-r--r--arch/x86/mm/pageattr.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index dd38bfbefd1f..b494fc4a986e 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -279,6 +279,20 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address,
__pa((unsigned long)__end_rodata) >> PAGE_SHIFT))
pgprot_val(forbidden) |= _PAGE_RW;
+#if defined(CONFIG_X86_64) && defined(CONFIG_DEBUG_RODATA)
+ /*
+ * Kernel text mappings for the large page aligned .rodata section
+ * will be read-only. For the kernel identity mappings covering
+ * the holes caused by this alignment can be anything.
+ *
+ * This will preserve the large page mappings for kernel text/data
+ * at no extra cost.
+ */
+ if (within(address, (unsigned long)_text,
+ (unsigned long)__end_rodata_hpage_align))
+ pgprot_val(forbidden) |= _PAGE_RW;
+#endif
+
prot = __pgprot(pgprot_val(prot) & ~pgprot_val(forbidden));
return prot;