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Date:   Mon, 14 Jan 2019 15:07:33 -0500 (EST)
From:   Dave Anderson <anderson@redhat.com>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Kazuhito Hagio <k-hagio@ab.jp.nec.com>,
        Lianbo Jiang <lijiang@redhat.com>,
        linux-kernel@vger.kernel.org, kexec@lists.infradead.org,
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        akpm@linux-foundation.org, bhe@redhat.com, dyoung@redhat.com,
        linux-doc@vger.kernel.org
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Subject: Re: [PATCH 1/2 v6] kdump: add the vmcoreinfo documentation
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Thread-Topic: kdump: add the vmcoreinfo documentation
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----- 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.
>