static int ignore_nmis;
+int unknown_nmi_panic;
+/*
+ * Prevent NMI reason port (0x61) being accessed simultaneously, can
+ * only be used in NMI handler.
+ */
+static DEFINE_RAW_SPINLOCK(nmi_reason_lock);
+
static inline void conditional_sti(struct pt_regs *regs)
{
if (regs->flags & X86_EFLAGS_IF)
die("general protection fault", regs, error_code);
}
-static notrace __kprobes void
-mem_parity_error(unsigned char reason, struct pt_regs *regs)
+static int __init setup_unknown_nmi_panic(char *str)
{
- printk(KERN_EMERG
- "Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
- reason, smp_processor_id());
+ unknown_nmi_panic = 1;
+ return 1;
+}
+__setup("unknown_nmi_panic", setup_unknown_nmi_panic);
- printk(KERN_EMERG
- "You have some hardware problem, likely on the PCI bus.\n");
+static notrace __kprobes void
+pci_serr_error(unsigned char reason, struct pt_regs *regs)
+{
+ pr_emerg("NMI: PCI system error (SERR) for reason %02x on CPU %d.\n",
+ reason, smp_processor_id());
+ /*
+ * On some machines, PCI SERR line is used to report memory
+ * errors. EDAC makes use of it.
+ */
#if defined(CONFIG_EDAC)
if (edac_handler_set()) {
edac_atomic_assert_error();
if (panic_on_unrecovered_nmi)
panic("NMI: Not continuing");
- printk(KERN_EMERG "Dazed and confused, but trying to continue\n");
+ pr_emerg("Dazed and confused, but trying to continue\n");
- /* Clear and disable the memory parity error line. */
- reason = (reason & 0xf) | 4;
- outb(reason, 0x61);
+ /* Clear and disable the PCI SERR error line. */
+ reason = (reason & NMI_REASON_CLEAR_MASK) | NMI_REASON_CLEAR_SERR;
+ outb(reason, NMI_REASON_PORT);
}
static notrace __kprobes void
{
unsigned long i;
- printk(KERN_EMERG "NMI: IOCK error (debug interrupt?)\n");
+ pr_emerg(
+ "NMI: IOCK error (debug interrupt?) for reason %02x on CPU %d.\n",
+ reason, smp_processor_id());
show_registers(regs);
if (panic_on_io_nmi)
panic("NMI IOCK error: Not continuing");
/* Re-enable the IOCK line, wait for a few seconds */
- reason = (reason & 0xf) | 8;
- outb(reason, 0x61);
+ reason = (reason & NMI_REASON_CLEAR_MASK) | NMI_REASON_CLEAR_IOCHK;
+ outb(reason, NMI_REASON_PORT);
- i = 2000;
- while (--i)
- udelay(1000);
+ i = 20000;
+ while (--i) {
+ touch_nmi_watchdog();
+ udelay(100);
+ }
- reason &= ~8;
- outb(reason, 0x61);
+ reason &= ~NMI_REASON_CLEAR_IOCHK;
+ outb(reason, NMI_REASON_PORT);
}
static notrace __kprobes void
return;
}
#endif
- printk(KERN_EMERG
- "Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
- reason, smp_processor_id());
+ pr_emerg("Uhhuh. NMI received for unknown reason %02x on CPU %d.\n",
+ reason, smp_processor_id());
- printk(KERN_EMERG "Do you have a strange power saving mode enabled?\n");
- if (panic_on_unrecovered_nmi)
+ pr_emerg("Do you have a strange power saving mode enabled?\n");
+ if (unknown_nmi_panic || panic_on_unrecovered_nmi)
panic("NMI: Not continuing");
- printk(KERN_EMERG "Dazed and confused, but trying to continue\n");
+ pr_emerg("Dazed and confused, but trying to continue\n");
}
static notrace __kprobes void default_do_nmi(struct pt_regs *regs)
{
unsigned char reason = 0;
- int cpu;
- cpu = smp_processor_id();
-
- /* Only the BSP gets external NMIs from the system. */
- if (!cpu)
- reason = get_nmi_reason();
-
- if (!(reason & 0xc0)) {
- if (notify_die(DIE_NMI_IPI, "nmi_ipi", regs, reason, 2, SIGINT)
- == NOTIFY_STOP)
- return;
+ /*
+ * CPU-specific NMI must be processed before non-CPU-specific
+ * NMI, otherwise we may lose it, because the CPU-specific
+ * NMI can not be detected/processed on other CPUs.
+ */
+ if (notify_die(DIE_NMI, "nmi", regs, 0, 2, SIGINT) == NOTIFY_STOP)
+ return;
-#ifdef CONFIG_X86_LOCAL_APIC
- if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT)
- == NOTIFY_STOP)
- return;
+ /* Non-CPU-specific NMI: NMI sources can be processed on any CPU */
+ raw_spin_lock(&nmi_reason_lock);
+ reason = get_nmi_reason();
-#ifndef CONFIG_LOCKUP_DETECTOR
+ if (reason & NMI_REASON_MASK) {
+ if (reason & NMI_REASON_SERR)
+ pci_serr_error(reason, regs);
+ else if (reason & NMI_REASON_IOCHK)
+ io_check_error(reason, regs);
+#ifdef CONFIG_X86_32
/*
- * Ok, so this is none of the documented NMI sources,
- * so it must be the NMI watchdog.
+ * Reassert NMI in case it became active
+ * meanwhile as it's edge-triggered:
*/
- if (nmi_watchdog_tick(regs, reason))
- return;
- if (!do_nmi_callback(regs, cpu))
-#endif /* !CONFIG_LOCKUP_DETECTOR */
- unknown_nmi_error(reason, regs);
-#else
- unknown_nmi_error(reason, regs);
+ reassert_nmi();
#endif
-
+ raw_spin_unlock(&nmi_reason_lock);
return;
}
- if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT) == NOTIFY_STOP)
- return;
+ raw_spin_unlock(&nmi_reason_lock);
- /* AK: following checks seem to be broken on modern chipsets. FIXME */
- if (reason & 0x80)
- mem_parity_error(reason, regs);
- if (reason & 0x40)
- io_check_error(reason, regs);
-#ifdef CONFIG_X86_32
- /*
- * Reassert NMI in case it became active meanwhile
- * as it's edge-triggered:
- */
- reassert_nmi();
-#endif
+ unknown_nmi_error(reason, regs);
}
dotraplinkage notrace __kprobes void
void stop_nmi(void)
{
- acpi_nmi_disable();
ignore_nmis++;
}
void restart_nmi(void)
{
ignore_nmis--;
- acpi_nmi_enable();
}
/* May run on IST stack. */
projects / mv-sheeva.git / blobdiff