releases/3.10.34/arm-7864-1-handle-64-bit-memory-in-case-of-32-bit-phys_addr_t.patch

   1 From 6d7d5da7d75c6df676c8b72d32b02ff024438f0c Mon Sep 17 00:00:00 2001
   2 From: Magnus Damm <damm@opensource.se>
   3 Date: Tue, 22 Oct 2013 17:59:54 +0100
   4 Subject: ARM: 7864/1: Handle 64-bit memory in case of 32-bit phys_addr_t
   5
   6 From: Magnus Damm <damm@opensource.se>
   7
   8 commit 6d7d5da7d75c6df676c8b72d32b02ff024438f0c upstream.
   9
  10 Use CONFIG_ARCH_PHYS_ADDR_T_64BIT to determine
  11 if ignoring or truncating of memory banks is
  12 neccessary. This may be needed in the case of
  13 64-bit memory bank addresses but when phys_addr_t
  14 is kept 32-bit.
  15
  16 Signed-off-by: Magnus Damm <damm@opensource.se>
  17 Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
  18 Cc: Wang Nan <wangnan0@huawei.com>
  19 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  20
  21 ---
  22  arch/arm/kernel/setup.c |   16 ++++++++++++----
  23  1 file changed, 12 insertions(+), 4 deletions(-)
  24
  25 --- a/arch/arm/kernel/setup.c
  26 +++ b/arch/arm/kernel/setup.c
  27 @@ -530,6 +530,7 @@ void __init dump_machine_table(void)
  28  int __init arm_add_memory(phys_addr_t start, phys_addr_t size)
  29  {
  30         struct membank *bank = &meminfo.bank[meminfo.nr_banks];
  31 +       u64 aligned_start;
  32
  33         if (meminfo.nr_banks >= NR_BANKS) {
  34                 printk(KERN_CRIT "NR_BANKS too low, "
  35 @@ -542,10 +543,16 @@ int __init arm_add_memory(phys_addr_t st
  36          * Size is appropriately rounded down, start is rounded up.
  37          */
  38         size -= start & ~PAGE_MASK;
  39 -       bank->start = PAGE_ALIGN(start);
  40 +       aligned_start = PAGE_ALIGN(start);
  41
  42 -#ifndef CONFIG_ARM_LPAE
  43 -       if (bank->start + size < bank->start) {
  44 +#ifndef CONFIG_ARCH_PHYS_ADDR_T_64BIT
  45 +       if (aligned_start > ULONG_MAX) {
  46 +               printk(KERN_CRIT "Ignoring memory at 0x%08llx outside "
  47 +                      "32-bit physical address space\n", (long long)start);
  48 +               return -EINVAL;
  49 +       }
  50 +
  51 +       if (aligned_start + size > ULONG_MAX) {
  52                 printk(KERN_CRIT "Truncating memory at 0x%08llx to fit in "
  53                         "32-bit physical address space\n", (long long)start);
  54                 /*
  55 @@ -553,10 +560,11 @@ int __init arm_add_memory(phys_addr_t st
  56                  * 32 bits, we use ULONG_MAX as the upper limit rather than 4GB.
  57                  * This means we lose a page after masking.
  58                  */
  59 -               size = ULONG_MAX - bank->start;
  60 +               size = ULONG_MAX - aligned_start;
  61         }
  62  #endif
  63
  64 +       bank->start = aligned_start;
  65         bank->size = size & ~(phys_addr_t)(PAGE_SIZE - 1);
  66
  67         /*