src/patches/suse-2.6.27.25/patches.suse/kdump-dump_after_notifier.patch

   1 From: Takenori Nagano <t-nagano@ah.jp.nec.com>
   2 Subject: [PATCH] Add dump_after_notifier sysctl
   3 Patch-mainline: never
   4 References: 265764
   5
   6 This patch adds dump_after_notifier sysctl to execute kdump after the notifier
   7 call chain. This basically makes it possible to execute KDB before kdump.
   8
   9 Signed-off-by: Takenori Nagano <t-nagano@ah.jp.nec.com>
  10 Acked-by: Bernhard Walle <bwalle@suse.de>
  11
  12 ---
  13  include/linux/kexec.h  |    2 ++
  14  include/linux/sysctl.h |    1 +
  15  kernel/kexec.c         |   29 +++++++++++++++++++++++++++++
  16  kernel/panic.c         |    5 ++++-
  17  kernel/sysctl_check.c  |    1 +
  18  5 files changed, 37 insertions(+), 1 deletion(-)
  19
  20 --- a/include/linux/kexec.h
  21 +++ b/include/linux/kexec.h
  22 @@ -154,6 +154,7 @@ unsigned long paddr_vmcoreinfo_note(void
  23
  24  extern struct kimage *kexec_image;
  25  extern struct kimage *kexec_crash_image;
  26 +extern int dump_after_notifier;
  27
  28  #ifndef kexec_flush_icache_page
  29  #define kexec_flush_icache_page(page)
  30 @@ -208,5 +209,6 @@ struct pt_regs;
  31  struct task_struct;
  32  static inline void crash_kexec(struct pt_regs *regs) { }
  33  static inline int kexec_should_crash(struct task_struct *p) { return 0; }
  34 +#define dump_after_notifier 0
  35  #endif /* CONFIG_KEXEC */
  36  #endif /* LINUX_KEXEC_H */
  37 --- a/include/linux/sysctl.h
  38 +++ b/include/linux/sysctl.h
  39 @@ -164,6 +164,7 @@ enum
  40         KERN_NMI_WATCHDOG=75, /* int: enable/disable nmi watchdog */
  41         KERN_PANIC_ON_NMI=76, /* int: whether we will panic on an unrecovered */
  42         KERN_KDB=77,            /* int: kdb on/off */
  43 +       KERN_DUMP_AFTER_NOTIFIER=78, /* int: kdump after panic_notifier (SUSE only) */
  44  };
  45
  46
  47 --- a/kernel/kexec.c
  48 +++ b/kernel/kexec.c
  49 @@ -30,6 +30,7 @@
  50  #include <linux/pm.h>
  51  #include <linux/cpu.h>
  52  #include <linux/console.h>
  53 +#include <linux/sysctl.h>
  54
  55  #include <asm/page.h>
  56  #include <asm/uaccess.h>
  57 @@ -45,6 +46,7 @@
  58
  59  /* Per cpu memory for storing cpu states in case of system crash. */
  60  note_buf_t* crash_notes;
  61 +int dump_after_notifier;
  62
  63  /* vmcoreinfo stuff */
  64  unsigned char vmcoreinfo_data[VMCOREINFO_BYTES];
  65 @@ -1151,6 +1153,30 @@ void crash_save_cpu(struct pt_regs *regs
  66         final_note(buf);
  67  }
  68
  69 +#ifdef CONFIG_SYSCTL
  70 +static ctl_table dump_after_notifier_table[] = {
  71 +       {
  72 +               .ctl_name = KERN_DUMP_AFTER_NOTIFIER,
  73 +               .procname = "dump_after_notifier",
  74 +               .data = &dump_after_notifier,
  75 +               .maxlen = sizeof(int),
  76 +               .mode = 0644,
  77 +               .proc_handler = &proc_dointvec,
  78 +       },
  79 +       { .ctl_name = 0 }
  80 +};
  81 +
  82 +static ctl_table kexec_sys_table[] = {
  83 +       {
  84 +               .ctl_name = CTL_KERN,
  85 +               .procname = "kernel",
  86 +               .mode = 0555,
  87 +               .child = dump_after_notifier_table,
  88 +       },
  89 +       { .ctl_name = 0 }
  90 +};
  91 +#endif
  92 +
  93  static int __init crash_notes_memory_init(void)
  94  {
  95         /* Allocate memory for saving cpu registers. */
  96 @@ -1160,6 +1186,9 @@ static int __init crash_notes_memory_ini
  97                 " states failed\n");
  98                 return -ENOMEM;
  99         }
 100 +#ifdef CONFIG_SYSCTL
 101 +       register_sysctl_table(kexec_sys_table);
 102 +#endif
 103         return 0;
 104  }
 105  module_init(crash_notes_memory_init)
 106 --- a/kernel/panic.c
 107 +++ b/kernel/panic.c
 108 @@ -95,7 +95,8 @@ NORET_TYPE void panic(const char * fmt,
 109          * everything else.
 110          * Do we want to call this before we try to display a message?
 111          */
 112 -       crash_kexec(NULL);
 113 +       if (!dump_after_notifier)
 114 +               crash_kexec(NULL);
 115
 116  #ifdef CONFIG_SMP
 117         /*
 118 @@ -108,6 +109,8 @@ NORET_TYPE void panic(const char * fmt,
 119
 120         atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
 121
 122 +       crash_kexec(NULL);
 123 +
 124         if (!panic_blink)
 125                 panic_blink = no_blink;
 126
 127 --- a/kernel/sysctl_check.c
 128 +++ b/kernel/sysctl_check.c
 129 @@ -106,6 +106,7 @@ static const struct trans_ctl_table tran
 130         { KERN_PANIC_ON_NMI,            "panic_on_unrecovered_nmi" },
 131         { KERN_SETUID_DUMPABLE,         "suid_dumpable" },
 132         { KERN_KDB,                     "kdb" },
 133 +       { KERN_DUMP_AFTER_NOTIFIER,     "dump_after_notifier" },
 134         {}
 135  };
 136