On Mon, 2006-06-12 at 09:50, Takao Indoh wrote: > On 09 Jun 2006 06:47:59 +0800, Zou Nan hai wrote: > > > Thanks for testing and review. > > > > There is still a lot of work to do for ia64 Kdump to be a very useful > >and robust feature. > > > > Major issues. > > 1. Full percpu dumping on INIT. > > You may notices I only send an IPI to user CPUs and dump part of > >registers for crashing CPU.Just stop other CPUs, not dumping their > >status. This is only a temp hack. > > On other platforms they did this by an NMI, on IA64 we should use INIT > >to acknowledge other CPUs. And I know on some platform there is a > >trigger on panel can trigger INIT. We could use that to dump at the time > >of deadlock. But currently INIT is used by MCA, we need to find a way to > >coordinate with MAC on INIT. > > > > 2. unwind section is missing in vmcore. > > When you do a readelf on vmcore, you may notice there is no unwind > >sections. We should add this percpu stack unwind sections to help dump > >filter tools to analize the core dump. > > > > 3. kdump path at crash time. > > Currently I still have to do a irq->end on each level triggered irq, > >without that the MPT fusion driver can not restart. We should fix this, > >at least do that in a way of not touching any memory in previous kernel. > > > > 4. Other than this, we need port the dump filter to IA64. > > > >There are still some minor issues. > >e.g > > When I get a crash when X is active, the new kernel will startup in a > >blank screen(network is still working). I have indeed do a brute force > >VGA reset on in purgatory code. But that seems to only shutdown the VGA > >but not reinit it if X is running. > > > > Current kexec can't not run on a kexec'd kernel, that is because the > >memory region of EFI memmap is not reserverd in /proc/iomem, I will sent > >a patch to reserve that region later. > > > >There should be other issues and gaps need to find out. > > > >Thanks > >Zou Nan hai > >- > >: send the line "unsubscribe linux-ia64" in > >the body of a message to majordomo@xxxxxxxxxxxxxxx > >More majordomo info at http://vger.kernel.org/majordomo-info.html > > Hi, > > I tried to use kdump on ia64, and it seemed to work, but > I was not able to execute back trace for the panic process using > crash tool. > > I think the reason is that 1st kernel does not save switch stack before > 2nd kernel boots. > > Do you have a plan to improve kdump to save switch stack? > Or is there another method to trace panic process? > Yes, I am going to dump per-cpu unwind sections to the core file. Thanks Zou Nan hai > Regards, > Takao Indoh - : send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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