Re: [PATCH 1/2 v6] kdump: add the vmcoreinfo documentation

Dave Anderson
2019-01-14T20:07:34Z

----- Original Message -----
> On Mon, Jan 14, 2019 at 02:36:47PM -0500, Dave Anderson wrote:
> > There's no reading of the dumpfile's memory involved, and that being the case,
> > the vmlinux file is not utilized. That's the whole point of the crash option, i.e.,
> > taking a vmcore file, and trying to determine what kernel should be used
> > with it:
> >
> > $ man crash
> > ...
> > --osrelease dumpfile
> > Display the OSRELEASE vmcoreinfo string from a kdump dumpfile header.
>
> I don't understand - if you have the vmcoreinfo (which I assume is part
> of the vmcore, yes, no?) you can go and dig out the kernel version from
> it, no?
>
> Why should you not utilize the vmcore file?

That's what it *does* utilize -- it takes a standalone vmcore dumpfile, and
pulls out the OSRELEASE string from it, so that a user can determine what
vmlinux file should be used with that vmcore for normal crash analysis.

Dave

>
> (I'm most likely missing something.)
>
> > Well, I just don't agree that the OSRELEASE item is "frivolous". It's
> > been in place, and depended upon, for many years.
>
> Yeah, no. The ABI argument is moot in this case as in the last couple
> of months people have been persuading me that vmcoreinfo is not ABI. So
> you guys need to make up your mind what is it. And if it is an ABI, it
> wasn't documented anywhere.
>
> --
> Regards/Gruss,
> Boris.
>
> Good mailing practices for 400: avoid top-posting and trim the reply.
>