[PATCH] tile: handle RO_AFTER_INIT_DATA

From: Chris Metcalf
Date: Mon Nov 07 2016 - 14:50:49 EST


This is the minimal change to handle RO_AFTER_INIT_DATA.
The tile architecture already marks RO_DATA as read-only in
the kernel, so grouping RO_AFTER_INIT_DATA with RO_DATA, as is
done by default, means the kernel faults in init when it tries
to write to RO_AFTER_INIT_DATA. For now, just move it past the
end of the RODATA section so it is not specially treated.
---
This is just to fix 4.9; I will post a more complete fix shortly
targeting 4.10.

arch/tile/kernel/vmlinux.lds.S | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/tile/kernel/vmlinux.lds.S b/arch/tile/kernel/vmlinux.lds.S
index e1baf094fba4..dcd7445c31a2 100644
--- a/arch/tile/kernel/vmlinux.lds.S
+++ b/arch/tile/kernel/vmlinux.lds.S
@@ -1,3 +1,6 @@
+/* Handle ro_after_init data on our own. */
+#define RO_AFTER_INIT_DATA
+
#include <asm-generic/vmlinux.lds.h>
#include <asm/page.h>
#include <asm/cache.h>
@@ -87,6 +90,7 @@ SECTIONS

_sdata = .; /* Start of data section */
RO_DATA_SECTION(PAGE_SIZE)
+ RO_AFTER_INIT_DATA
RW_DATA_SECTION(L2_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
_edata = .;

--
2.7.2