[PATCH] kexec: force x86_64 arches to boot kdump kernels on boot cpu
vgoyal at redhat.com
Fri Nov 30 09:35:34 EST 2007
On Fri, Nov 30, 2007 at 12:59:26AM -0800, Yinghai Lu wrote:
> On Nov 29, 2007 6:54 PM, Eric W. Biederman <ebiederm at xmission.com> wrote:
> > Ben Woodard <woodard at redhat.com> writes:
> > > Eric W. Biederman wrote:
> > >> Vivek Goyal <vgoyal at redhat.com> writes:
> > >>
> > >>> Ok. Got it. So in this case we route the interrupts directly through LAPIC
> > >>> and put LVT0 in ExtInt mode and IOAPIC is bypassed.
> > >>>
> > >>> I am looking at Intel Multiprocessor specification v1.4 and as per figure
> > >>> 3-3 on page 3-9, 8259 is connected to LINTIN0 line, which in turn is
> > >>> connected to LINTIN0 pin on all processors. If that is the case, even in
> > >>> this mode, all the CPU should see the timer interrupts (which is coming
> > >>> from 8259)?
> > >>
> there is two mode for mcp55. bios should have one option about virtul
> wired to LVT0 of BSP or IOAPIC pin 0.
> or the option like hpet route to ioapic pin 2.
That's interesting. So with BIOS options I can force timer
interrupts to be routed through IOAPIC? That would enable us to get
timer interrupts on any of the cpus in legacy mode. Ben, can you give it
> for kdump fix, could enable LVT0 of CPU for kdump and disable that for BSP?
We would not know the crashing cpu in advance hence can't set it.
More information about the kexec