[PATCH 4.2.y-ckt 027/273] ARM: OMAP2+: Fix l2dis_3630 for rodata

From: Kamal Mostafa
Date: Mon Mar 07 2016 - 19:48:09 EST


4.2.8-ckt5 -stable review patch. If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Tony Lindgren <tony@xxxxxxxxxxx>

commit eeaf9646aca89d097861caa24d9818434e48810e upstream.

We don't want to write to .text section. Let's move l2dis_3630
to .data and access it via a pointer.

For calculating the offset, let's optimize out the add and do it
in ldr/str as suggested by Nicolas Pitre <nicolas.pitre@xxxxxxxxxx>.

Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Laura Abbott <labbott@xxxxxxxxxx>
Cc: Nishanth Menon <nm@xxxxxx>
Cc: Richard Woodruff <r-woodruff2@xxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxxx>
Cc: Tero Kristo <t-kristo@xxxxxx>
Acked-by: Nicolas Pitre <nico@xxxxxxxxxx>
Fixes: 1e6b48116a95 ("ARM: mm: allow non-text sections to be
non-executable")
Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
arch/arm/mach-omap2/sleep34xx.S | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach-omap2/sleep34xx.S
index 787cfda..5659d96 100644
--- a/arch/arm/mach-omap2/sleep34xx.S
+++ b/arch/arm/mach-omap2/sleep34xx.S
@@ -86,8 +86,9 @@ ENTRY(enable_omap3630_toggle_l2_on_restore)
stmfd sp!, {lr} @ save registers on stack
/* Setup so that we will disable and enable l2 */
mov r1, #0x1
- adrl r2, l2dis_3630 @ may be too distant for plain adr
- str r1, [r2]
+ adrl r3, l2dis_3630_offset @ may be too distant for plain adr
+ ldr r2, [r3] @ value for offset
+ str r1, [r2, r3] @ write to l2dis_3630
ldmfd sp!, {pc} @ restore regs and return
ENDPROC(enable_omap3630_toggle_l2_on_restore)

@@ -415,7 +416,9 @@ ENTRY(omap3_restore)
cmp r2, #0x0 @ Check if target power state was OFF or RET
bne logic_l1_restore

- ldr r0, l2dis_3630
+ adr r1, l2dis_3630_offset @ address for offset
+ ldr r0, [r1] @ value for offset
+ ldr r0, [r1, r0] @ value at l2dis_3630
cmp r0, #0x1 @ should we disable L2 on 3630?
bne skipl2dis
mrc p15, 0, r0, c1, c0, 1
@@ -484,7 +487,9 @@ l2_inv_gp:
mov r12, #0x2
smc #0 @ Call SMI monitor (smieq)
logic_l1_restore:
- ldr r1, l2dis_3630
+ adr r0, l2dis_3630_offset @ adress for offset
+ ldr r1, [r0] @ value for offset
+ ldr r1, [r0, r1] @ value at l2dis_3630
cmp r1, #0x1 @ Test if L2 re-enable needed on 3630
bne skipl2reen
mrc p15, 0, r1, c1, c0, 1
@@ -513,6 +518,10 @@ control_stat:
.word CONTROL_STAT
control_mem_rta:
.word CONTROL_MEM_RTA_CTRL
+l2dis_3630_offset:
+ .long l2dis_3630 - .
+
+ .data
l2dis_3630:
.word 0

--
2.7.0