[PATCH 2/7] powerpc: move __end_rodata to cover arch read-only sections

[Nicholas Piggin]

powerpc has a number of read-only sections and tables that are put
after RO_DATA(). Move the __end_rodata symbol to cover these as well.

Setting memory to read-only at boot is done using __init_begin,
change that that to use __end_rodata.

This also affects boot dmesg, is_kernel_rodata(), and some other checks.

Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
---
 arch/powerpc/kernel/vmlinux.lds.S        | 3 +++
 arch/powerpc/mm/book3s32/mmu.c           | 2 +-
 arch/powerpc/mm/book3s64/hash_pgtable.c  | 2 +-
 arch/powerpc/mm/book3s64/radix_pgtable.c | 2 +-
 arch/powerpc/mm/pgtable_32.c             | 5 ++---
 5 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index fe22d940412f..90ac5ff73df2 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -210,6 +210,9 @@ SECTIONS
 	}
 #endif
 
+	. = ALIGN(PAGE_SIZE);
+	__end_rodata = .;
+
 /*
  * Init sections discarded at runtime
  */
diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c
index a96b73006dfb..e13b883e4e5b 100644
--- a/arch/powerpc/mm/book3s32/mmu.c
+++ b/arch/powerpc/mm/book3s32/mmu.c
@@ -240,7 +240,7 @@ void mmu_mark_rodata_ro(void)
 	for (i = 0; i < nb; i++) {
 		struct ppc_bat *bat = BATS[i];
 
-		if (bat_addrs[i].start < (unsigned long)__init_begin)
+		if (bat_addrs[i].start < (unsigned long)__end_rodata)
 			bat[1].batl = (bat[1].batl & ~BPP_RW) | BPP_RX;
 	}
 
diff --git a/arch/powerpc/mm/book3s64/hash_pgtable.c b/arch/powerpc/mm/book3s64/hash_pgtable.c
index ae008b9df0e6..28332001bd87 100644
--- a/arch/powerpc/mm/book3s64/hash_pgtable.c
+++ b/arch/powerpc/mm/book3s64/hash_pgtable.c
@@ -541,7 +541,7 @@ void hash__mark_rodata_ro(void)
 	unsigned long start, end, pp;
 
 	start = (unsigned long)_stext;
-	end = (unsigned long)__init_begin;
+	end = (unsigned long)__end_rodata;
 
 	pp = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL_ROX), HPTE_USE_KERNEL_KEY);
 
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 698274109c91..2305f34bcc33 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -228,7 +228,7 @@ void radix__mark_rodata_ro(void)
 	unsigned long start, end;
 
 	start = (unsigned long)_stext;
-	end = (unsigned long)__init_begin;
+	end = (unsigned long)__end_rodata;
 
 	radix__change_memory_range(start, end, _PAGE_WRITE);
 }
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 3ac73f9fb5d5..112af8c5447a 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -158,10 +158,9 @@ void mark_rodata_ro(void)
 	}
 
 	/*
-	 * mark .text and .rodata as read only. Use __init_begin rather than
-	 * __end_rodata to cover NOTES and EXCEPTION_TABLE.
+	 * mark .text and .rodata as read only.
 	 */
-	numpages = PFN_UP((unsigned long)__init_begin) -
+	numpages = PFN_UP((unsigned long)__end_rodata) -
 		   PFN_DOWN((unsigned long)_stext);
 
 	set_memory_ro((unsigned long)_stext, numpages);
-- 
2.37.2