releases/4.20.6/arc-adjust-memblock_reserve-of-kernel-memory.patch

   1 From a3010a0465383300f909f62b8a83f83ffa7b2517 Mon Sep 17 00:00:00 2001
   2 From: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
   3 Date: Wed, 19 Dec 2018 19:16:16 +0300
   4 Subject: ARC: adjust memblock_reserve of kernel memory
   5
   6 From: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
   7
   8 commit a3010a0465383300f909f62b8a83f83ffa7b2517 upstream.
   9
  10 In setup_arch_memory we reserve the memory area wherein the kernel
  11 is located. Current implementation may reserve more memory than
  12 it actually required in case of CONFIG_LINUX_LINK_BASE is not
  13 equal to CONFIG_LINUX_RAM_BASE. This happens because we calculate
  14 start of the reserved region relatively to the CONFIG_LINUX_RAM_BASE
  15 and end of the region relatively to the CONFIG_LINUX_RAM_BASE.
  16
  17 For example in case of HSDK board we wasted 256MiB of physical memory:
  18 ------------------->8------------------------------
  19 Memory: 770416K/1048576K available (5496K kernel code,
  20     240K rwdata, 1064K rodata, 2200K init, 275K bss,
  21     278160K reserved, 0K cma-reserved)
  22 ------------------->8------------------------------
  23
  24 Fix that.
  25
  26 Fixes: 9ed68785f7f2b ("ARC: mm: Decouple RAM base address from kernel link addr")
  27 Cc: stable@vger.kernel.org      #4.14+
  28 Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
  29 Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
  30 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  31
  32 ---
  33  arch/arc/mm/init.c |    3 ++-
  34  1 file changed, 2 insertions(+), 1 deletion(-)
  35
  36 --- a/arch/arc/mm/init.c
  37 +++ b/arch/arc/mm/init.c
  38 @@ -137,7 +137,8 @@ void __init setup_arch_memory(void)
  39          */
  40
  41         memblock_add_node(low_mem_start, low_mem_sz, 0);
  42 -       memblock_reserve(low_mem_start, __pa(_end) - low_mem_start);
  43 +       memblock_reserve(CONFIG_LINUX_LINK_BASE,
  44 +                        __pa(_end) - CONFIG_LINUX_LINK_BASE);
  45
  46  #ifdef CONFIG_BLK_DEV_INITRD
  47         if (initrd_start)