src/patches/suse-2.6.27.31/patches.arch/s390-09-03-sclp-mem.patch

   1 From: Gerald Schaefer <geraldsc@de.ibm.com>
   2 Subject: sclp: consider "mem=" kernel parameter for standby memory
   3 References: bnc#477666,LTC#51741
   4
   5 Symptom:     zfcpdump exits with "panic: out of memory"
   6 Problem:     Standby memory detected with the sclp interface always gets
   7              registered with add_memory calls without considering the
   8              limitations that the "mem=" kernel paramater imply.
   9              zfcpdump uses "mem=32M". In case there is approximately 2GB of
  10              standby memory present all usable memory will be used for
  11              struct pages needed for standby memory. This in turn leads
  12              to an early out of memory situation and a panic.
  13 Solution:    Only register standby memory that is below the address specified
  14              with the "mem=" kernel parameter.
  15
  16 Acked-by: John Jolly <jjolly@suse.de>
  17 ---
  18  arch/s390/include/asm/setup.h |    2 ++
  19  arch/s390/kernel/setup.c      |    9 +++++++--
  20  drivers/s390/char/sclp_cmd.c  |    5 +++++
  21  3 files changed, 14 insertions(+), 2 deletions(-)
  22
  23 Index: linux-sles11/arch/s390/include/asm/setup.h
  24 ===================================================================
  25 --- linux-sles11.orig/arch/s390/include/asm/setup.h
  26 +++ linux-sles11/arch/s390/include/asm/setup.h
  27 @@ -43,6 +43,8 @@ struct mem_chunk {
  28
  29  extern struct mem_chunk memory_chunk[];
  30  extern unsigned long real_memory_size;
  31 +extern int memory_end_set;
  32 +extern unsigned long memory_end;
  33
  34  void detect_memory_layout(struct mem_chunk chunk[]);
  35
  36 Index: linux-sles11/arch/s390/kernel/setup.c
  37 ===================================================================
  38 --- linux-sles11.orig/arch/s390/kernel/setup.c
  39 +++ linux-sles11/arch/s390/kernel/setup.c
  40 @@ -81,7 +81,9 @@ char elf_platform[ELF_PLATFORM_SIZE];
  41
  42  struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
  43  volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
  44 -static unsigned long __initdata memory_end;
  45 +
  46 +int __initdata memory_end_set;
  47 +unsigned long __initdata memory_end;
  48
  49  /*
  50   * This is set up by the setup-routine at boot-time
  51 @@ -280,6 +282,7 @@ void (*pm_power_off)(void) = machine_pow
  52  static int __init early_parse_mem(char *p)
  53  {
  54         memory_end = memparse(p, &p);
  55 +       memory_end_set = 1;
  56         return 0;
  57  }
  58  early_param("mem", early_parse_mem);
  59 @@ -501,8 +504,10 @@ static void __init setup_memory_end(void
  60         int i;
  61
  62  #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
  63 -       if (ipl_info.type == IPL_TYPE_FCP_DUMP)
  64 +       if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
  65                 memory_end = ZFCPDUMP_HSA_SIZE;
  66 +               memory_end_set = 1;
  67 +       }
  68  #endif
  69         memory_size = 0;
  70         memory_end &= PAGE_MASK;
  71 Index: linux-sles11/drivers/s390/char/sclp_cmd.c
  72 ===================================================================
  73 --- linux-sles11.orig/drivers/s390/char/sclp_cmd.c
  74 +++ linux-sles11/drivers/s390/char/sclp_cmd.c
  75 @@ -18,6 +18,7 @@
  76  #include <linux/memory.h>
  77  #include <asm/chpid.h>
  78  #include <asm/sclp.h>
  79 +#include <asm/setup.h>
  80
  81  #include "sclp.h"
  82
  83 @@ -470,6 +471,10 @@ static void __init add_memory_merged(u16
  84                 goto skip_add;
  85         if (start + size > VMEM_MAX_PHYS)
  86                 size = VMEM_MAX_PHYS - start;
  87 +       if (memory_end_set && (start >= memory_end))
  88 +               goto skip_add;
  89 +       if (memory_end_set && (start + size > memory_end))
  90 +               size = memory_end - start;
  91         add_memory(0, start, size);
  92  skip_add:
  93         first_rn = rn;