Re: Query: Kdump: Core Image ELF Format

[ebiederm@xmission.com (Eric W. Biederman)]

Vivek Goyal <vgoyal@in.ibm.com> writes:

> On Wed, 2005-03-23 at 13:26 +0900, Fernando Luis Vazquez Cao wrote:
> > Hi all.
> > 
> > On Tue, 2005-03-08 at 18:20 +0530, vivek goyal wrote:
> > > Core image ELF headers are prepared before crash and stored at a safe
> > > place in memory. These headers are retrieved over a kexec boot and final
> > > elf core image is prepared for analysis. 
> > 
> > Regarding the preparation of the ELF headers, I think we should also
> > take into consideration hot-plug memory and create appropriate
> > mechanisms to deal with it.
> > 
> > Assuming that both insertion and removal of memory trigger a hotplug
> > event that is subsequently handled by the relevant hotplug agent(*), the
> > latter could be modified so that, on successful memory onlining,
> > additional PT_LOAD headers are created and tucked in a safe place
> > together with the others.
> 
> I think, re-loading the panic kernel in such event should be an easier
> solution. Current kexec system call interface does not allow to read
> back already stored segments, which is necessary to append new PT_LOAD
> headers to the existing program header list and update ELF header.

I thought that is what he was describing.

Eric