Messages in this thread | ![/](/images/icornerl.gif) | | Date | Fri, 12 Dec 2003 14:27:38 -0800 | From | George Anzinger <> | Subject | Re: Catching NForce2 lockup with NMI watchdog |
| |
Having had cause to try and figure out all this, I vote for the following being included in the source somewhere...
-g
bill davidsen wrote: > In article <Pine.LNX.4.55.0312101421540.31543@jurand.ds.pg.gda.pl>, > Maciej W. Rozycki <macro@ds2.pg.gda.pl> wrote: > > | The I/O APIC NMI watchdog utilizes the property of being transparent to a > | single IRQ source of a specially reconfigured 8259A PIC (the master one in > | the IA32 PC architecture). There are more prerequisites that have to be > | met and all indeed are for a 100% compatible PC as specified by the > | Intel's Multiprocessor Specification. > | > | 1. The INT output of the master 8259A PIC has to be connected to the LINT0 > | (or LINTIN0; the name varies by implementations) inputs of all local APICs > | in the system. > | > | 2a. The OUT0 output of the 8254 PIT (IOW the timer source) has to be > | directly connected to the INTIN2 input of the first I/O APIC. > | > | 2b. Alternatively the INT output of the master 8259A PIC has to be > | connected to the INTIN0 input of the first I/O APIC. > | > | 3. There must be no glue logic that would change logical properties of the > | signal between the INT output of the master 8259A PIC and the respective > | APIC interrupt inputs. > | > | In practice, assuming the MP IRQ routing information provided the BIOS has > | been correct (which is not always the case), prerequisites #1 and #2 have > | been met so far, but #3 has proved to be occasionally problematic. > > In practice many system seem to take a good bit of guessing and testing. > I have an old P-II which only works with acpi=force and nmi_watchdog=2, > for instance. > > It would be nice if there were a program which could poke at the > hardware and suggest options which might work, as in eliminating the > ones which can be determined not to work. Absent that trial and error > rule, unfortunately.
-- George Anzinger george@mvista.com High-res-timers: http://sourceforge.net/projects/high-res-timers/ Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| ![\](/images/icornerr.gif) |