releases/4.9.30/arm-8670-1-v7m-do-not-corrupt-vector-table-around-v7m_invalidate_l1-call.patch

   1 From 6d80594936914e798b1b54b3bfe4bd68d8418966 Mon Sep 17 00:00:00 2001
   2 From: Vladimir Murzin <vladimir.murzin@arm.com>
   3 Date: Mon, 24 Apr 2017 10:40:48 +0100
   4 Subject: ARM: 8670/1: V7M: Do not corrupt vector table around v7m_invalidate_l1 call
   5
   6 From: Vladimir Murzin <vladimir.murzin@arm.com>
   7
   8 commit 6d80594936914e798b1b54b3bfe4bd68d8418966 upstream.
   9
  10 We save/restore registers around v7m_invalidate_l1 to address pointed
  11 by r12, which is vector table, so the first eight entries are
  12 overwritten with a garbage. We already have stack setup at that stage,
  13 so use it to save/restore register.
  14
  15 Fixes: 6a8146f420be ("ARM: 8609/1: V7M: Add support for the Cortex-M7 processor")
  16 Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
  17 Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
  18 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  19
  20 ---
  21  arch/arm/mm/proc-v7m.S |    4 ++--
  22  1 file changed, 2 insertions(+), 2 deletions(-)
  23
  24 --- a/arch/arm/mm/proc-v7m.S
  25 +++ b/arch/arm/mm/proc-v7m.S
  26 @@ -147,10 +147,10 @@ __v7m_setup_cont:
  27
  28         @ Configure caches (if implemented)
  29         teq     r8, #0
  30 -       stmneia r12, {r0-r6, lr}        @ v7m_invalidate_l1 touches r0-r6
  31 +       stmneia sp, {r0-r6, lr}         @ v7m_invalidate_l1 touches r0-r6
  32         blne    v7m_invalidate_l1
  33         teq     r8, #0                  @ re-evalutae condition
  34 -       ldmneia r12, {r0-r6, lr}
  35 +       ldmneia sp, {r0-r6, lr}
  36
  37         @ Configure the System Control Register to ensure 8-byte stack alignment
  38         @ Note the STKALIGN bit is either RW or RAO.