src/patches/suse-2.6.27.31/patches.suse/panic-on-io-nmi.diff

   1 From: Kurt Garloff <garloff@suse.de>
   2 Subject: [PATCH] X86: sysctl to allow panic on IOCK NMI error
   3 References: bnc427979
   4
   5 This patch introduces a sysctl /proc/sys/kernel/panic_on_io_nmi.,
   6 which defaults to 0 (off).
   7 When enabled, the kernel panics when the kernel receives an NMI
   8 caused by an IO error.
   9
  10 The IO error triggered NMI indicates a serious system condition,
  11 which could result in IO data corruption. Rather than contiuing,
  12 panicing and dumping might be a better choice, so one can figure
  13 out what's causing the IO error.
  14 This could be especially important to companies running IO intensive
  15 applications where corruption must be avoided, e.g. a banks databases.
  16
  17
  18 Signed-off-by: Roberto Angelino <robertangelino@gmail.com>
  19
  20
  21 ---
  22  arch/x86/kernel/traps_32.c |    4 ++++
  23  arch/x86/kernel/traps_64.c |    4 ++++
  24  include/linux/kernel.h     |    1 +
  25  include/linux/sysctl.h     |    1 +
  26  kernel/sysctl.c            |    8 ++++++++
  27  kernel/sysctl_check.c      |    1 +
  28  6 files changed, 19 insertions(+)
  29
  30 --- a/arch/x86/kernel/traps_32.c
  31 +++ b/arch/x86/kernel/traps_32.c
  32 @@ -83,6 +83,7 @@ gate_desc idt_table[256]
  33         __attribute__((__section__(".data.idt"))) = { { { { 0, 0 } } }, };
  34
  35  int panic_on_unrecovered_nmi;
  36 +int panic_on_io_nmi;
  37  int kstack_depth_to_print = 24;
  38  static unsigned int code_bytes = 64;
  39  #ifdef CONFIG_STACK_UNWIND
  40 @@ -779,6 +780,9 @@ io_check_error(unsigned char reason, str
  41         printk(KERN_EMERG "NMI: IOCK error (debug interrupt?)\n");
  42         show_registers(regs);
  43
  44 +       if (panic_on_io_nmi)
  45 +               panic("NMI IOCK error: Not continuing");
  46 +
  47         /* Re-enable the IOCK line, wait for a few seconds */
  48         reason = (reason & 0xf) | 8;
  49         outb(reason, 0x61);
  50 --- a/arch/x86/kernel/traps_64.c
  51 +++ b/arch/x86/kernel/traps_64.c
  52 @@ -56,6 +56,7 @@
  53  #include <mach_traps.h>
  54
  55  int panic_on_unrecovered_nmi;
  56 +int panic_on_io_nmi;
  57  int kstack_depth_to_print = 12;
  58  static unsigned int code_bytes = 64;
  59  #ifdef CONFIG_STACK_UNWIND
  60 @@ -840,6 +841,9 @@ io_check_error(unsigned char reason, str
  61         printk("NMI: IOCK error (debug interrupt?)\n");
  62         show_registers(regs);
  63
  64 +       if (panic_on_io_nmi)
  65 +               panic("NMI IOCK error: Not continuing");
  66 +
  67         /* Re-enable the IOCK line, wait for a few seconds */
  68         reason = (reason & 0xf) | 8;
  69         outb(reason, 0x61);
  70 --- a/include/linux/kernel.h
  71 +++ b/include/linux/kernel.h
  72 @@ -236,6 +236,7 @@ extern int oops_in_progress;                /* If set,
  73  extern int panic_timeout;
  74  extern int panic_on_oops;
  75  extern int panic_on_unrecovered_nmi;
  76 +extern int panic_on_io_nmi;
  77  extern int tainted;
  78  extern int unsupported;
  79  extern const char *print_tainted(void);
  80 --- a/include/linux/sysctl.h
  81 +++ b/include/linux/sysctl.h
  82 @@ -165,6 +165,7 @@ enum
  83         KERN_PANIC_ON_NMI=76, /* int: whether we will panic on an unrecovered */
  84         KERN_KDB=77,            /* int: kdb on/off */
  85         KERN_DUMP_AFTER_NOTIFIER=78, /* int: kdump after panic_notifier (SUSE only) */
  86 +       KERN_PANIC_ON_IO_NMI=79, /* int: whether we will panic on an io NMI */
  87  };
  88
  89
  90 --- a/kernel/sysctl.c
  91 +++ b/kernel/sysctl.c
  92 @@ -691,6 +691,14 @@ static struct ctl_table kern_table[] = {
  93                 .proc_handler   = &proc_dointvec,
  94         },
  95         {
  96 +               .ctl_name       = KERN_PANIC_ON_IO_NMI,
  97 +               .procname       = "panic_on_io_nmi",
  98 +               .data           = &panic_on_io_nmi,
  99 +               .maxlen         = sizeof(int),
 100 +               .mode           = 0644,
 101 +               .proc_handler   = &proc_dointvec,
 102 +       },
 103 +       {
 104                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 105                 .procname       = "bootloader_type",
 106                 .data           = &bootloader_type,
 107 --- a/kernel/sysctl_check.c
 108 +++ b/kernel/sysctl_check.c
 109 @@ -104,6 +104,7 @@ static const struct trans_ctl_table tran
 110         { KERN_MAX_LOCK_DEPTH,          "max_lock_depth" },
 111         { KERN_NMI_WATCHDOG,            "nmi_watchdog" },
 112         { KERN_PANIC_ON_NMI,            "panic_on_unrecovered_nmi" },
 113 +       { KERN_PANIC_ON_IO_NMI,         "panic_on_io_nmi" },
 114         { KERN_SETUID_DUMPABLE,         "suid_dumpable" },
 115         { KERN_KDB,                     "kdb" },
 116         { KERN_DUMP_AFTER_NOTIFIER,     "dump_after_notifier" },