> --- linux.orig/include/asm-x86_64/nmi.h > +++ linux/include/asm-x86_64/nmi.h > @@ -63,7 +63,7 @@ extern int setup_nmi_watchdog(char *); > > extern atomic_t nmi_active; > extern unsigned int nmi_watchdog; > -#define NMI_DEFAULT -1 > +#define NMI_DEFAULT 0
Maybe I'm missing something obvious, but this patch doesn't seem correct to me. The sentiment of disabling the NMI watchdog by default is fine, and I agree with it, but I don't think this patch does what it says. First of all, I have a system running a kernel with this patch applied (v2.6.21-rc2-gc3442e2), and I see NMIs in /proc/interrupts and "testing NMI watchdog ... OK." in the log. And second, looking at the NMI code, it seems that this change actually makes it impossible to turn off the NMI watchdog! In arch/x86_64/kernel/nmi.c, we have: void nmi_watchdog_default(void) { if (nmi_watchdog != NMI_DEFAULT) return; if (nmi_known_cpu()) nmi_watchdog = NMI_LOCAL_APIC; else nmi_watchdog = NMI_IO_APIC; } so it seems changing the value of NMI_DEFAULT has no effect on this logic, really: if nmi_watchdog is left at the default, then the kernel chooses LAPIC or IO-APIC. And if someone passes "nmi_watchdog=0" on the command line, nmi_watchdog is still NMI_DEFAULT and so the same logic triggers. Ingo, I assume you tested this, so what am I missing? - R. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/