jam-08-memparam.patch

   1         Fix mem=XXX kernel parameter when user gives a size bigger than what
   2         kernel autodetected (kill a previous change)
   3         Author: Adrian Bunk <bunk@fs.tum.de>,
   4                         Leonardo Gomes Figueira <sabbath@planetarium.com.br>
   5
   6 --- linux/arch/i386/kernel/setup.c.original     Mon Jul 22 21:44:45 2002
   7 +++ linux/arch/i386/kernel/setup.c      Tue Jul 23 03:38:08 2002
   8 @@ -770,21 +770,29 @@
   9                                 userdef = 1;
  10                         } else {
  11                                 /* If the user specifies memory size, we
  12 -                                * limit the BIOS-provided memory map to
  13 -                                * that size. exactmap can be used to specify
  14 -                                * the exact map. mem=number can be used to
  15 -                                * trim the existing memory map.
  16 +                                * blow away any automatically generated
  17 +                                * size
  18                                  */
  19                                 unsigned long long start_at, mem_size;
  20
  21 +                               if (userdef == 0) {
  22 +                                       /* first time in: zap the whitelist
  23 +                                        * and reinitialize it with the
  24 +                                        * standard low-memory region.
  25 +                                        */
  26 +                                       e820.nr_map = 0;
  27 +                                       userdef = 1;
  28 +                                       add_memory_region(0, LOWMEMSIZE(), E820_RAM);
  29 +                               }
  30                                 mem_size = memparse(from+4, &from);
  31 -                               if (*from == '@') {
  32 +                               if (*from == '@')
  33                                         start_at = memparse(from+1, &from);
  34 -                                       add_memory_region(start_at, mem_size, E820_RAM);
  35 -                               } else {
  36 -                                       limit_regions(mem_size);
  37 +                               else {
  38 +                                       start_at = HIGH_MEMORY;
  39 +                                       mem_size -= HIGH_MEMORY;
  40                                         userdef=1;
  41                                 }
  42 +                               add_memory_region(start_at, mem_size, E820_RAM);
  43                         }
  44                 }
  45