From b849a60e0903b1c5430c3859864554662e127a8d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Mon, 16 Jan 2012 10:34:31 +0100 Subject: ARM: make cr_alignment read-only #ifndef CONFIG_CPU_CP15 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Message-Id: 1358413196-5609-2-git-send-email-u.kleine-koenig@pengutronix.de (v8) --- arch/arm/kernel/head-common.S | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'arch/arm/kernel/head-common.S') diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 854bd22380d3..5b391a689b47 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -98,8 +98,9 @@ __mmap_switched: str r9, [r4] @ Save processor ID str r1, [r5] @ Save machine type str r2, [r6] @ Save atags pointer - bic r4, r0, #CR_A @ Clear 'A' bit - stmia r7, {r0, r4} @ Save control register values + cmp r7, #0 + bicne r4, r0, #CR_A @ Clear 'A' bit + stmneia r7, {r0, r4} @ Save control register values b start_kernel ENDPROC(__mmap_switched) @@ -113,7 +114,11 @@ __mmap_switched_data: .long processor_id @ r4 .long __machine_arch_type @ r5 .long __atags_pointer @ r6 +#ifdef CONFIG_CPU_CP15 .long cr_alignment @ r7 +#else + .long 0 @ r7 +#endif .long init_thread_union + THREAD_START_SP @ sp .size __mmap_switched_data, . - __mmap_switched_data -- cgit v1.2.2