powerpc/mm/hash: Implement mark_rodata_ro() for hash
With hash we update the bolted pte to mark it read-only. We rely
on the MMU_FTR_KERNEL_RO to generate the correct permissions
for read-only text. The radix implementation just prints a warning
in this implementation
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[mpe: Make the warning louder when we don't have MMU_FTR_KERNEL_RO]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index bce0ed5..fc2e6de 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -491,3 +491,16 @@ void mmu_partition_table_set_entry(unsigned int lpid, unsigned long dw0,
}
EXPORT_SYMBOL_GPL(mmu_partition_table_set_entry);
#endif /* CONFIG_PPC_BOOK3S_64 */
+
+#ifdef CONFIG_STRICT_KERNEL_RWX
+void mark_rodata_ro(void)
+{
+ if (!mmu_has_feature(MMU_FTR_KERNEL_RO)) {
+ pr_warn("Warning: Unable to mark rodata read only on this CPU.\n");
+ return;
+ }
+
+ if (!radix_enabled())
+ hash__mark_rodata_ro();
+}
+#endif