[RFC PATCH v2 15/18] arm64: lds: move idmap_pg_dir out of .rodata

[Ard Biesheuvel]

After future changes, the ID map may be set up by the boot entry code
with the MMU and caches enabled, which means we will reuse the identity
map set up by the firmware. This means that memory we describe as
read-only in the PE/COFF header may not be writable, preventing us from
creating the new identity map if the root level is located in such a
region.

Signed-off-by: Ard Biesheuvel <ardb at kernel.org>
---
 arch/arm64/kernel/vmlinux.lds.S | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index edaf0faf766f..2231ccba45f7 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -194,10 +194,6 @@ SECTIONS
 
 	HYPERVISOR_DATA_SECTIONS
 
-	idmap_pg_dir = .;
-	. += IDMAP_DIR_SIZE;
-	idmap_pg_end = .;
-
 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
 	tramp_pg_dir = .;
 	. += PAGE_SIZE;
@@ -291,6 +287,11 @@ SECTIONS
 		__mmuoff_data_end = .;
 	}
 
+	. = ALIGN(PAGE_SIZE);
+	idmap_pg_dir = .;
+	. += IDMAP_DIR_SIZE;
+	idmap_pg_end = .;
+
 	PECOFF_EDATA_PADDING
 	__pecoff_data_rawsize = ABSOLUTE(. - __initdata_begin);
 	_edata = .;
-- 
2.30.2