ARM: make cr_alignment read-only #ifndef CONFIG_CPU_CP15

This makes cr_alignment a constant 0 to break code that tries to modify
the value as it's likely that it's built on wrong assumption when
CONFIG_CPU_CP15 isn't defined. For code that is only reading the value 0
is more or less a fine value to report.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Message-Id: 1358413196-5609-2-git-send-email-u.kleine-koenig@pengutronix.de (v8)

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
index b820edaf3184..feeb3eaccb1c 100644
--- a/arch/arm/mm/alignment.c
+++ b/arch/arm/mm/alignment.c
@@ -964,12 +964,14 @@ static int __init alignment_init(void)
                 return -ENOMEM;
 #endif
 
+#ifdef CONFIG_CPU_CP15
         if (cpu_is_v6_unaligned()) {
                 cr_alignment &= ~CR_A;
                 cr_no_alignment &= ~CR_A;
                 set_cr(cr_alignment);
                 ai_usermode = safe_usermode(ai_usermode, false);
         }
+#endif
 
         hook_fault_code(FAULT_CODE_ALIGNMENT, do_alignment, SIGBUS, BUS_ADRALN,
                         "alignment exception");